Title: The Nephrite Jade Road: Evolution of the Green Nephrite Market Abstract: Emperors’ stamps once symbolized highly centralized power. Almost all were made of nephrite jade, chosen for its unequaled rarity, durability, and beauty. They’re no longer in use, but today many of China’s organizations use nephrite stamps to depict major events. This is the official stamp of the 2010 Shanghai World Expo. It’s made of a piece of top-quality light green nephrite weighing 4.28 kilograms (about 9 lbs.). It was carved by Master Zhang Tiecheng to mimic the style of the stamp used by Emperor Qianlong, historically known as jade’s biggest fan. Courtesy of China Gems magazine.

	INTRODUCTION

	The Chinese character “Yu” is equivalent to the English term “jade,” but the term’s meaning has broadened to include both nephrite and jadeite jade. Some even use the word to refer to all beautiful rocks, demonstrating the significance of jade in the Chinese culture. Record-setting prices for jadeite jade jewelry have been in the industry news spotlight for the past 30 years. However, nephrite jade has been an important part of China’s jade culture for more than 5,000 years. And nephrite’s history on other continents goes back 4,000 to 5,000 years.

	The name jade had always applied to nephrite until jadeite jade was imported into China about 200 to 250 years ago. In China, jade symbolizes a connection between the living and the dead as well as power, wealth, and social class. Also used to fashion tools, jade is a part of every aspect of people’s lives.

	To display their pride in jade culture, the Chinese mounted nephrite jade into the award medals used in the 2008 Beijing Olympic Games. It was the first time that gem materials were used on Olympic medals and it reignited an awareness of, and love for, nephrite jade.

The Beijing Olympics medals were mounted with nephrite sourced in Qinghai province, China. It was a highly successful promotion that drove up sales and facilitated the nephrite jade rush in Canada and Russia that occurred in 2009 and 2010. Courtesy China Gems Magazine.

	In China, nephrite names are based on color. White nephrite has always been and still is the most highly revered. Owning a piece of white, or “mutton fat,” nephrite is the dream of all jade collectors. Next on the popularity list is green nephrite. It has the same hue as the most valuable jadeite jade but it’s not as bright. The slightly weaker luster gives it a more conservative look. Green nephrite has attracted consumer attention due to the recently skyrocketing prices of white nephrite and good-quality jadeite jade.

The “Ban Zhi” ring was once worn on a man’s thumb and designed with a very thick shank to protect the skin during archery practice. It later evolved into a symbol of wealth and power. This one is attached to a beaded string for hanging on a belt. Courtesy Beijing Boguan Auction House.

	While very few people question China’s status as the largest nephrite jade market, the sourcing, manufacturing, and trading of the stone have never stopped evolving. Today, nephrite holds an exalted place in the Chinese market, motivating Canadian and Russian miners. Since Chinese green nephrite production keeps shrinking, the main products on the market are from these two sources. History, production, and trading policies, and the demand from China, combine to influence the modern green nephrite market.

	COMMERCIALLY IMPORTANT SOURCES

	Green nephrite occurs along the contacts between serpentinite units and more silicic (rich in silica) rocks such as granitic intrusive bodies, argillite, chert, or greywacke in obduction settings, where continental and oceanic crusts collide (Harlow at al., 2005). Its formation results from metasomatic reactions promoted by the presence of calcium-rich hydrous fluid along the contacts (Harlow et al., 2005).

	Although deposits around the globe share a similar geological setting, there is no single formation model. Since serpentinite belongs to ophiolite belts and ophiolite is of oceanic origin, it’s only transported to land by subduction or obduction. Subduction and obduction occur during continental-oceanic collisions, so most ophiolite belts occur along old suture zones and current subduction zones.

Major green nephrite deposits form within serpentinite belts along old or still-active subduction zones. The three most commercially important deposits—in China, British Columbia, and Siberia—all have similar geological environments. Map adapted from Harlow and Sorensen, 2005.

	The most economically important green nephrite sources are located in northwestern China, British Columbia, and Siberia. They are all major suppliers for the China market.

	XINJIANG, CHINA

	Hetian, also known as Hotan, is located in northwestern China (Xinjiang Uygur Autonomous Region) and has always been synonymous with the best nephrite. The area is known for yielding the famous top-quality white “mutton fat” jade.

	Traditionally named “Hetian Jade” is mainly from the Kunlun (Karakoram) and A’erjin (Altai) Mountains. Most of the production from these two areas is white, light greenish white, or light green. Nephrite with a very obvious green hue is called “green nephrite” (“Bi Yu” in Chinese). Most green jade production is from the Manasi River Valley in the south of Jungar Basin. Primary deposits are located on the north slope of the Tian Shan (or Tien Shan) Mountains. In the trade it is called “Manasi green jade.

	Hetian is generally considered a source of the best-quality nephrite, while Manasi produces
	most of the green nephrite from Xinjiang. Manasi County is located in northwestern Xingjiang,
	along the Kunlun Mountains.

	The mining of Manasi green nephrite has a long history. During the Qing dynasty, it was completely controlled by the imperial court. In 1789, Emperor Qianlong ordered the closing of the area’s green nephrite mines. After that, the mines were dormant for more than 180 years. In 1973, the topic of green nephrite resources and mining was raised in a national meeting. This facilitated the reopening of the old mines and exploration in search of new resources.

	Local government support led to the establishment of a nephrite carving factory in Manasi County in 1974. That year, green nephrite production reached several tens of tons. The rough was transported to carving factories in southern China. Finished products mainly supplied the domestic market.

	BRITISH COLUMBIA, CANADA

	There are more than 50 nephrite occurrences in British Columbia (Simandl et al., 2000 ogden mine article), all distributed along the Cordilleran belt that extends from Alaska to California at irregular intervals along the continent’s margins (Leaming, 1995). This belt includes different regions of oceanic origin that contain the rocks necessary for green nephrite formation. These regions became part of the continent during subduction that occurred in the Mesozoic (Davis et al., 1978).

Nephrite deposits are distributed along a belt of ultramafic (igneous, with very low silica content) rocks that extends over 1,000 miles from the Canada-US border northwest through central and northern British Columbia, all the way to the Yukon border. Three clusters of nephrite deposits formed along this belt: southern, central, and northern clusters.

	Until the 1960s, almost all of the nephrite produced in British Columbia came from secondary deposits. With the rapid expansion of amateur lapidary activity after World War II, production in British Columbia’s jade fields picked up and they became the most important suppliers. About the same time, markets opened up in Germany and the Orient. Mining activity gradually depleted the secondary deposits, but increasing values led to further exploration. These efforts uncovered primary deposits adjacent to the Fraser River area in southern British Columbia, the Mount Ogden area in central British Columbia, and the Cassiar jade fields in the far north. Today, British Columbia is the main supplier for the China market.

The primary nephrite deposits in British Columbia are all located in highly mountainous areas. This is a view of the Jade Mountains in the province’s northwest corner. The extremely rugged terrain and harsh winters make nephrite mining very challenging. Courtesy of Jade West Group.

	Jade West Group, founded in 1981, is the biggest player in green nephrite mining and trading in British Columbia. Kirk Makepeace, the company’s founder, is an avid promoter of the stone. He started with a summer job as a jade driller. This involved flying into remote areas and spending summers in tents, with supplies brought by small planes every two weeks. Carrying drills in a backpack, he hiked the countryside in search of jade boulders. He drilled cores from them to determine potential quality. About three out of 100 boulders he drilled were of marketable quality.

	More than thirty years later, Jade West has become one of the world’s leading producers and exporters of green nephrite jade. The company owns and operates three out of the four active nephrite mines in British Columbia, including the famous Polar Mine near Dease Lake, and the Kutcho and Ogden Mountain mines. The Polar Mine’s high-quality production is known as Polar Jade in the trade.

Secondary deposits have been exhausted, so nephrite mining in British Columbia is now mainly mechanized. Costs are high, but the richness of the deposits still makes it a very rewarding business. Courtesy of Jade West Group.

The Polar Pride boulder—called “the find of the millennium” by trade experts—was discovered in 2000. The 18-ton boulder was split in half for carving. Courtesy of Jade West Group.

	Nephrite mining in British Columbia is very challenging. Winters are long and harshly cold, and deposits are remote, so mining can only happen during the short summer season, about 60 days a year. Almost all of the secondary deposits are exhausted, so current mining is almost all from primary deposits. Transporting the heavy equipment to the mining sites is backbreaking work.

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	British Columbia Nephrite Mining Gallery

	Jade West uses diamond-coated circular and wire saws and modern high-pressure hydraulic splitters to remove the nephrite from the mountain and saw it into pieces of a manageable size.  Nephrite’s excellent toughness makes it extremely difficult to break out of the rock. While blasting had been used in the past, Jade West no longer uses explosives.

	Nephrite deposits range from 12 inches to 12 feet wide. The wider deposits are very challenging to quarry. Nephrite boulders on the surface sometimes reach weights of 200 tons and are rarely under 100 pounds, but Jade West tries to limit the weight of its boulders to five tons, which is a reasonable size for them to mine, handle, and transport on trucks to the nearest town, about 100 miles away. The average weight is two tons, a size that satisfies most of the carving factories in China.

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	Nephrite Mining in British Columbia Gallery

	Sophisticated exploration techniques and an understanding of the area’s geology are the keys to successful mining operations and lengthening of a mine’s productive life. Jade West Group invests a lot of capital in its exploration projects. The company adopted core drilling in 1975, and it’s still their most powerful and reliable exploration tool. They drill into the mountain with water-cooled diamond-tipped drills, then extract the cores and examine them to determine if the nephrite is of suitable quality to turn into a marketable finished product. Since the mining season is short, the miners must call on a great deal of experience when determining the areas from which they will take core samples.

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	Exploration Gallery

	SIBERIA, RUSSIA

	Although it entered the China market only about 10 to 15 years ago, green nephrite from Russia has gained a great reputation because of its bright color and good transparency. Both white and green nephrite are mined in Russia. Some of the white stones can be of equal quality to the most sought-after “mutton fat” jade and can be sold for high prices in China. Green nephrite is more readily available than the white varieties.

	The first green nephrite boulders were discovered on riverbanks in Russia’s Sayan area in 1826. There were additional discoveries in 1851 along the Onot River. The first primary nephrite deposit was reportedly discovered in 1986 (Burtseva et al., 2015).

All of Russia’s nephrite mining areas have spectacular views of snow-capped mountains, valleys, and rivers. Courtesy Sibirgeology, Russia.

	Siberian nephrite mines are located in extremely remote areas of Russia, in the Eastern Sayan Mountains and the Dzhida areas to the southwest of Lake Baikal, along with the Parama massif to the northeast of the lake. The Sayan Mountains are geographically and geologically related to the Altai Mountains that cross northwestern China, northern Mongolia, and Southwestern Russia. Many people believe that this connection is the reason for the similar qualities of nephrite from China and Russia.

	The main green nephrite deposits in the Eastern Sayan Mountains and Dzhida areas are
	located to the southwest of Lake Baikal. The entire area covers more than 250 square
	kilometers. Map adapted from Burtseva et al., 2015.

	This chalice is fashioned in a style common to Faberge products. The nephrite was
	mined in Siberia a long time ago. Material of this quality is very hard to find today.
	Courtesy Jade West Group.

	The green nephrite mines that the Chinese are familiar with are almost all clustered in the Eastern Sayan Mountains. From 2005 until now, Chinese nephrite dealers have been sourcing much of their inventory from these mines. Located along the southern margin of the Siberian craton, this area covers over 250 square kilometers. The Russians have recognized and carefully studied more than 50 ultramafic rock units (Burtseva et al., 2015), almost all within the Ospa-Kitoi and Khara-Nur massifs.

	The three largest green nephrite mines include Ospa (known to the Chinese as #7 and #11 mines), Gorlygol (known to the Chinese as #10 mine) and Ulankhoda. There are 15 recognized nephrite veins in the Ospa deposit, more than 30 in Gorlygol, and more than 20 in Ulankhoda (Burtseva et al., 2015). Green nephrite formation occurs along the contact between serpentinites and metasomatized mafic and felsic dikes (Burtseva et al., 2015).

The terrain in the Siberian nephrite mining areas is extremely rugged. The best way to access these areas is by helicopter. Retired army helicopters are often hired to transport people and supplies to the mining sites. Courtesy Sibirgeology, Russia.

	The mining of Siberian green nephrite is extremely challenging due to a combination of harsh weather conditions and extremely rugged local terrain. The mining sites can best be accessed by helicopter in the summer or by heavy duty trucks along frozen rivers in winter. Explorers need to fly to Irkutsk, the nearest transitional city, and start from there. It takes at least four to five days to reach the mining sites. Retired six-wheel army trucks are the most available and reliable transport vehicles.

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	Hard Journey to the Mine Gallery

	Russian geologist Dr. Sasha Sekerin was one of the earliest explorers of nephrite deposits in the Western and Eastern Sayan Mountains. Today, he remains a highly respected jade expert in Russia. Dr. Sekerin served as a research scientist in the Zemnoy Kory (Earth Crust) Institute in Irkutsk for over a decade until the Soviet Union fell apart. He then became a nephrite jade miner. Sasha and his colleagues began exploring the area in 1975 and have guided foreign explorers and nephrite investors to the area over the past decade.

Dr. Sasha Sekerin is highly respected as a nephrite jade expert in Russia. He began exploring the nephrite deposits in Siberia in the 1970s. After the Soviet Union collapsed he became a nephrite jade miner. Courtesy Sibirgeology, Russia.

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	Nephrite Deposits in Siberia Gallery

	To mine the nephrite, miners inject expansion agents into fractures in the giant rocks. They limit the use of explosives to protect the nephrite from damage. After injecting the agents, they wait a year, during which natural temperature changes help to fracture the rocks and get them ready for the mining season. The miners label the rocks to avoid conflicting claims, but due to increasing demand and skyrocketing prices, some locals will risk extracting the labeled claims during the winter. Large extracted nephrite is sawn on-site so it’s a reasonable size for transport.

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	Siberian Nephrite Mining Operations Gallery

	MARKET EVOLUTION

	North American nephrite tools found in British Columbia’s Cariboo region date back more than 4,000 years, but the region’s green nephrite did not find its way into the market until independent Chinese miners recognized it during the 1850s gold rush in California and British Columbia’s Fraser River area. They shipped nephrite boulders from both areas back to China for processing. Some of the top-quality material was taken by the imperial court and became part of its collection. Since then, British Columbia’s green nephrite has been imported continuously into China.

This map depicts the mine-to-market route of green nephrite. Canada and Russia are the two main suppliers to the Chinese market while China’s Xinjiang is a minor supplier. Almost all goods are processed in southern China, with Guangzhou as the hub. Finished products are sold mostly in China’s domestic market while a minor portion is exported to other countries.

	From 1885 to 1949, green nephrite from British Columbia was entering the China market through different channels, but the amounts were quite limited. The scarcity made this material quite expensive to obtain. In the early 1930s, one of four then-famous jade carvers created a premium carving using a huge piece of green nephrite rough from British Columbia. This rough was reportedly bought at an auction with a final price of 6000 silver dollars, China’s currency of the time. History’s best estimate of the average annual income at the time was about 250 silver dollars for people working in big cities such as Shanghai and Beijing. This meant that a normal city worker had to work for 24 years to make enough money to purchase nephrite rough.

Green nephrite from British Columbia is a very popular gem material for carving in China. This miniature folded screen features green nephrite panels mounted in wood frames. It mimics the full-size screen that is a typical traditional Chinese furniture piece used to maintain privacy in a certain area in a room. Courtesy Jade West Group.

	In the 1980s, Kirk Makepeace of Jade West Group was buying out failed jade mining companies. At that time, almost all the country’s nephrite was being exported to Taiwan. The Taiwanese market could not consume all the production and carved a lot of the material into trinkets and extremely inexpensive jewelry for the domestic market and for export. Mainland China’s market was not yet open and the inexpensive jewelry market provided enough demand to aid the development of the Canadian nephrite mining industry and allow it to dominate for almost 30 years. Mr. Makepeace recalls six- to eight-millimeter good-quality nephrite bead strands selling in the tourist stores of San Francisco’s Chinatown for five dollars each in the early 1980s.

Almost all of British Columbia’s production was exported to China, including Taiwan. Almost all carving and manufacturing take place in mainland China. Courtesy Jade West Group.

	Jade West Group began exporting nephrite into China in 1986 and found market resistance to accepting nephrite from Canada as jade. However, Mr. Makepeace had a strong feeling about the future of China’s nephrite market. He was quoted in a September 1987 National Geographic article on jade as saying, “My secret weapon is China. I’ve broken into that market. Last year I sold about 104 tons: 100 to China and only 4 to Taiwan.” After 2000, the demand from China increased dramatically as China’s growing middle class had more disposable income to spend.  Nephrite jade was a very affordable alternative to jadeite jade while still allowing much higher prices as compared to the decades when it was sold just as a trinket.

Since the Chinese are the main consumers of green nephrite, almost all of the carving designs are customized for this target group. Once in a while, a non-traditional feature will appear, such as the faceted beads in these bracelets. Courtesy Jade West Group.

	When Mr. Makepeace went to Hetian, he found that most of the green “Hetian nephrite” was actually from British Columbia. Local merchants sold them as Hetian jade to take advantage of the overwhelming historical reputation of that material and the higher price that was possible because of it (Glaude Adams, 2009).

	Today, both British Columbian and Siberian green nephrite are more respected in China. More and more dealers are willing to disclose the real origin of their inventory to consumers, but selling everything as Hetian jade is still quite common in local markets. In a local Hetian jade trading center, among the 500 to 600 shops, only five were carrying inventory made of Xinjiang Manasi green nephrite in 2012. Recent reports suggest that this situation is still about the same.

The green nephrite bangles in the China market are mainly from British Columbia and Siberia. It is very rare to see good-quality goods made of Xingjiang material. Courtesy Jade West Group.

	Siberian green nephrite first entered the China market in the early 1990s through the border trading town of Dongning in Heilongjiang Province, China. There are more than a hundred nephrite jade dealers doing business in Dongning. Between 2005 and 2011, due to the shortage of rough, the price of white nephrite skyrocketed from $500 to $10,000 a kilo, making it unaffordable for the majority of consumers. This opened the opportunity for large amounts of well-priced green nephrite to be imported into China. Between 2005 and 2008, Siberian green nephrite gained a lot of respect from Chinese consumers. Bangles and beads from the Ospa #7 deposit became a consumer favorite, while material from Gorlygol #10 was used mainly for carvings.

	This piece of green nephrite rough from Siberia possesses very intense color. It’s called
	“spinach green” in China and the trade considers it the best green nephrite color. Photo
	by Robert Weldon, courtesy Jade West Group

	As you’ve read, the nephrite market’s most important event was the Beijing 2008 Olympics, where the medals incorporated nephrite jade from China. The Chinese government created an educational and promotional campaign to explain its significance. This completely changed the market for nephrite in China, as demand and prices increased. Jade West’s price for top-quality rough nephrite from Canada was twenty dollars a kilo just before the Olympics. Today the top qualities sell for prices between $200 and $2,000 a kilo.

This Maori-style pendant is made of green nephrite from a Siberian deposit (#10). Although most of the production from this deposit is only good for carving, top-quality material can be used in jewelry. Courtesy Jade Factory and Jade Mountain.

	The Beijing Olympic Games also boosted the price of green nephrite imported from Russia, especially the nice-quality rough from the Ospa #7 deposit. After 2008, a mine-to-market green nephrite relationship formed between Russia and China. Siberian nephrite trading and carving centers were formed in Beijing, Ha’erbin, Henan and border towns such as Dongning and Manchuria.

	Realizing nephrite’s great economic potential, Russian miners and dealers keep raising the price of nephrite rough. At the same time, the Russian government limits the amount of nephrite being exported to China. Both factors put pressure on Chinese business owners and caused prices to jump even higher. At the beginning of 2013, Siberian green nephrite rough was imported at an average price of about US$500 to $650 a kilo. At the end of 2014, the average price in the Dongning market was about US$1000 a kilo. High-quality cat’s-eye Siberian green nephrite rough reached a price of US$50,000 a kilo in 2015, while the non-cat’s-eye top-quality material was priced at US$2000 a kilo.

	This necklace features top-quality cat’s-eye green nephrite cabochons. The apple-green
	color and the quality of the chatoyancy make this material a favorite of Chinese consumers.
	Courtesy Jade Factory and Jade Mountain.

	Siberian green nephrite now dominates the middle to high-end green nephrite market in China, while British Columbia material dominates the lower-end market. Though Xinjiang is historically the most important nephrite source, this is not true of green nephrite. The market share of Xinjiang green nephrite is very limited and can’t compete with Siberian and British Columbia products.

	PRODUCTION DICTATES MARKET SHARE

	Though Manasi green nephrite is a local product and bears the longest history in China, limited production gives it an awkward position in the current nephrite market. Annual production is about 40 tons, with a very low percentage of high-quality rough. This explains why it’s difficult to find Manasi jade jewelry, even in the local market in Xinjiang.

	Since 1973, annual production has ranged from one ton to about 35 tons. Between 1973 and 1978, production was pretty high, with an average of 15 tons per year. Between 1981 and 1988, annual production decreased to about 5 tons. Though Manasi jade and Hetian jade boast the highest reputation in China, they make up a minority of the market due to very limited production.

This Hetian green nephrite carving was fashioned by Master Carver Yan Guiming, and represents the best-quality material from Xingjiang, China. It is in the collection of the China National Arts & Crafts Museum. The rough came from a secondary deposit. Courtesy China Gems Magazine.

	.While demand from China has changed over the years, production from Canada has not changed dramatically. Canada exports about 400 tons of nephrite a year, a relatively small amount when compared to Myanmar’s jadeite exports, at 20,000 tons a year. Any price increase is primarily due to the domestic demand in China, rather than the nephrite pieces exported from Taiwan as inexpensive tourist souvenirs. Over the last 10 years, about 90 percent of Jade West’s production has gone to Mainland China, with approximately five percent to Taiwan and five percent to Vietnam and Thailand.

	Comparatively small amounts go to Germany and North America. The nephrite that goes to China is primarily for the Chinese domestic market. Thailand, Vietnam, Nepal and some other Southeast Asian countries buy nephrite for religious carvings of Buddha. Native Americans in the Pacific Northwest used nephrite as a tool but, unlike in China, never incorporated it in any culturally significant way. Canada’s domestic market consumes about five tons of rough a year, supplying a few local high-end carving artists.

	Half of the “Polar Pride” boulder recovered in British Columbia was carved into the famous
	4.65-ton “Jade Buddha for Universal Peace.” It was carved in Thailand over a two-year
	period. It is about 2.5 meters (about 8 feet) tall—the largest Buddha ever carved from
	gem-quality nephrite. Since 2009, the Jade Buddha has been on a tour of more than 15
	countries to inspire people to seek peace in their lives. Courtesy of Jade West Group.

	Before 1999, with limited average annual production of 20 tons, Siberian nephrite only supplied the Russian and European market. Between 2000 and 2002, annual production increased from about 40 tons to 100 tons.

	Before 2005, mining nephrite was not actually profitable for Siberian miners. This was due to the high mining, transportation, and processing costs, which contrasted sharply with the low price of the rough. The average price for Siberian green nephrite rough was only $1.5 to $5 a kilo, which in most cases didn’t even cover mining costs. In addition, only about 30 percent of the mined material had commercial value. Large-scale mining of nephrite did not happen in Siberia until after 2005.

In 2009, miners found a nearly five-ton green nephrite boulder along the Arahushun River in Siberia. Expansion agent was placed in the boulder, and after a year, miners split the cracked boulder into smaller pieces and transported them to the town. Photo courtesy of Jade Factory and Jade Mountain.

	After 2005, consumer focus switched to green nephrite due to the skyrocketing price of white nephrite. This suddenly made mining in Siberia very profitable, leading to an increase in production. From 2008 to 2010, annual production in Siberia increased from around 100 tons to about 500 tons. When #7 and #10 deposits were getting close to exhaustion around 2009 and 2010, main production came from newly exploited #37, #32 and #36 deposits. Green nephrite from these newer deposits is an increasing presence in the China market.

Nephrite jade expert Dr. Sasha Sekerin checks the quality of a giant piece of rough. Pouring water on the surface reveals the color better. Courtesy of Jade Factory and Jade Mountain.

	Overall, the green nephrite market in China is dominated by goods from Canada and Russia, with sporadic supplies from Xinjiang. Each source’s market share is dictated mostly by its production levels.

	CONSUMER PREFERENCES

	Although every source produces a whole range of materials with different qualities, there are some characteristics that are preferred by consumers. Color is green nephrite’s most important value factor. Chinese literature encompasses many different shades of green, and the preferred nephrite color is highly influenced by that for jadeite jade. Color, texture, and clarity are all important value factors that affect the price. In addition, different demographic groups have different tastes and preferences.

In this thin section of green nephrite from the #10 deposit in Siberia, the black dots are chromite and the whitish strips are parallel tremolite crystals. Courtesy Jade Factory and Jade Mountain.

	Green nephrite from all three main sources shares some features. The main mineral is tremolite. “Black dots” are common inclusions, determined by gemological research to be chromite. The Chinese trade term “waterline” refers to the whitish stripes that are, in fact, parallel tremolite crystals. Researchers think that the bright green is mainly caused by chromium ions, while iron ions also make a contribution.

	These bangles show different shades of green coloring. The bright green one is from Siberia
	while the dark green one is from the Ogden Mountain mine in British Columbia. Siberian
	materials generally have brighter color than those from Canada and China. Photo by Robert
	Weldon, courtesy Jade West Group.

	Manasi green nephrite normally has more “black dots” and slightly darker green color. Although top-quality Manasi jade can be compared to the top-quality material from Hetian and Siberia, it is very hard to find. The majority of the production is used for large-scale nephrite carvings rather than jewelry. Many Xinjiang dealers feel that it is hard to sell jewelry made of Manasi green nephrite because the price is fairly high, so they have less desire to spend money on Manasi inventory.

	Green nephrite from British Columbia usually has more “black dots” and “waterline” than Siberian material, although its top-quality goods can compete with the Siberian top quality. Most British Columbian production is priced to satisfy the middle to lower-end market. Some of the material contains some greenish dots that turned out to be chrome grossular garnet (Sun and Wang, 2014).

	The slightly darker green color of British Columbia nephrite actually falls into the color variety called “spinach green” in the trade. It is a slightly grayish or bluish green that is favored by older consumers and people who prefer a more conservative look. Spinach green has always been the most-desired green nephrite color. Though it’s not as bright, it matches very well with nephrite’s conservative image in the Chinese market.

	The whale tail design is made of Siberian green nephrite, while the base is carved from
	British Columbia material. When viewed together, the differences in color and color
	distribution are clearly visible. Courtesy of Jade West Group.

	British Columbia’s most famous green nephrite is Polar Jade from the Polar Mine. The mine’s green nephrite has a brighter green color than other British Columbia materials. Its Chinese name loosely means “jade from the Arctic circle,” which has become a successful name for promotional purposes. The Jade West Group, which owns and operates the mine, says that its production has become very limited.

The beads in the strand are from the Polar Mine in British Columbia. Polar Jade is considered the best of British Columbia’s green nephrite production. There is no active mining going on there at the moment, making the available goods even more valuable. The rough is from Wyoming, US, where mining has also ceased. This rough represents its best-quality material. Courtesy Jade West Group.

	Of the three main sources, top-quality Siberian green nephrite can have very fine texture and the vivid green color that’s especially favored by young consumers. Because it tends to have fewer “black dots” and well-distributed color, modern green nephrite items usually seen in auctions are mostly made of Siberian materials (per Ao Yan comment).

	The general impression among consumers is that Siberian green nephrite is generally higher in quality than material from Xinjiang or British Columbia. Its market price is correspondingly higher. According to Nikki Makepeace, the sales manager of Jade West Group, the manufacturing cost for Siberian material is a lot higher than that for Canadian or Chinese materials. When they send the Siberian material to China for fashioning, it often costs five to six times more than the British Columbia nephrite.

This suite of 18 arhats—followers of Buddha—was carved from Siberian green nephrite. The color distribution in top-quality Siberian green nephrite can be extremely even, as seen in the absence of black dots in these figures. Courtesy Beijing Boguan Auction House.

	The best Siberian material comes from the Ospa #7 deposit. Its green color is well distributed and it has fewer black dots and super-fine texture. Unfortunately, resources from the original deposit were mostly exhausted in 2010. Though geologists predict that there is still about 1,000 tons of material remaining, the depth of the ore bodies makes it too expensive to extract. In 2009, miners started extracting green nephrite from a neighboring deposit. Its production is similar in quality to the #7 material.

	CARVING AND MANUFACTURING

	The carving of nephrite has a history that goes back thousands of years. The craft reached its peak during the Qing dynasty. Emperor Qianlong, the biggest fan of both jadeite and nephrite jade, transported the best rough from Xinjiang province to Yangzhou, a town in Southern China, for carving. Yangzhou craftspeople have always been considered the best nephrite jade artisans, owing to generations of history-making jade carvers. Today, the best-quality green nephrite is still carved in Yangzhou, even though the manufacturing and carving capacity in Guangzhou is a lot higher and their craftspeople are very good.

A carver in Guangzhou is carving a piece of green nephrite from British Columbia. The plaque displays traditional Chinese themes and patterns. Courtesy Jade West Group.

	Before nephrite from Siberia and British Columbia became more respected in China, many master carvers refused to carve these foreign materials. Today, due partially to increased knowledge and understanding of the sources, the situation has changed. The quality of green nephrite from Siberia and British Columbia is now highly respected and appreciated by carvers all over China.

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	Traditional Carvings Gallery

	When describing the carving of nephrite, Kirk Makepeace explained the differences between carvings sold in China and those exported for the Western market. The Chinese carvings are closely related to the country’s culture, executed with a high degree of passion and skill. They typically depict traditional Chinese themes and often are highly detailed.

	Their themes are not appreciated as much in the West, so carvings for that market display a much simpler, less labor intensive carving style and themes that are more marketable in the West. The Western designs are often based on native Inuit soapstone carvings. Western people also like to use nephrite that is not gem-quality in their home decor. Mr. Makepeace said that appreciation for nephrite is increasing in the North American market. People have come to a much greater understanding of what nephrite is and place a higher value on it today.

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	Nephrite Jade Decorations Gallery

	TRADE STANDARDS

	Since China is the main market for nephrite jade, the local industry has tried for decades to establish a grading standard. However, due to the complexity of the material, this is still a work in progress. One recent change in the national standard of gemstone names is to broaden the definition of “Hetian Jade.” Chinese dealers take advantage of the fact that the name is fairly well-known by selling almost all their nephrite inventory as “Hetian jade” in order to increase their profits. Meanwhile, actual top-quality Hetian nephrite is extremely rare.

	Green nephrite from Siberia and British Columbia can be of higher quality but because it is not from Xinjiang, the price differences might not be equivalent. The new national standard allows all green nephrite to be named “Hetian Jade” on reports. The effect of this change is still unknown. It will take a while for the trade and consumers to provide informative feedback.

This strand is composed of high-quality, Siberian nephrite beads. Courtesy Jade West Group.

	The constantly increasing price for nephrite in general has forced source areas to develop local grading standards. The most recent is the Manasi green nephrite grading standard issued by the Xinjiang Uyghur Autonomous Region Quality Supervision Bureau. The standard applies to the green nephrite mined in Xinjiang. Its purpose is to further regulate the local rough nephrite market. This standard uses color, texture, and clarity as the main value factors for evaluating Manasi green nephrite into four different grades: Excellent, Good, Fine, and Poor.

	Jade West grades nephrite for their customers using AAA, AA, A, B, and C categories. Triple A is applied to the most expensive bracelets and pendants and accounts for 3 percent of the company’s production. Most of the jewelry from Jade West’s production is AA to A, with carvings often fashioned from the B and C grades. The carving-quality material represents about 70 percent of production and sells for $20 to $30 dollars a kilo in rough form. Lower grades are used for translucent tiles, burial caskets, and a wide variety of industrial or ornamental uses. The industrial grades have more muted color and higher concentrations of black inclusions, which are often magnetite and fractures. A similar rough-grading system also works for Siberian green nephrite rough.

This carved bangle is made of AA-grade Siberian green nephrite. Courtesy Jade West Group.

	TRADING IN CHINA

	Owing to the fast-growing gem and jewelry market in mainland China, there are multiple sales channels for green nephrite. These include wholesale trading centers, retail stores, online sites, and auction houses.

A buyer checks the quality of a piece of white nephrite jade at the preview of an auction. Courtesy Beijing Boguan Auction House.

	Large jade trading centers usually carry both nephrite and jadeite jade of different shapes and sizes. Trading centers in China that specialize in nephrite jade are mainly clustered in the areas close to the source in Xinjiang. In Urumqi, there are over 1,300 individual nephrite businesses in five major trading centers, local street markets, and more. Xinjiang dealers trade in goods from all different sources. Trading centers and retail stores in the border towns near Russia deal mainly in imported Siberian nephrite. Large jade markets in Guangdong carry both jadeite and nephrite jade and they source material from all over the world.

	Retail stores specializing in nephrite are more and more common in major cities. Although their sales still can’t compare to trading centers, many business owners already realize the importance of branding even for nephrite jade. Unlike the sales-oriented trading centers, retail stores have much more flexibility to develop special displays and consumer services. Nephrite branding is primarily dedicated to passing on the nephrite culture.

Branded nephrite jade is still not quite as common as jadeite jade or other gemstone jewelry. Jade Factory is a nephrite jade jewelry brand that operates stores both overseas and in mainland China. Courtesy Jade Factory and Jade Mountain.

	Along with the rapid development of e-commerce in every field, online jade trading platforms and websites for individual businesses are also quite common. Because there is still no universal grading standard for jade, there are many problems associated with online jade purchases. Buyers have to be extra cautious when buying jade online unless they know they are dealing with a trustworthy source. Commercial-quality or lower-quality jade jewelry still makes up the bulk of online sales. Consumers prefer to see the jade in person and up close in most cases.

	Auction houses are an important selling channel for higher-end goods and antiques. Major auction houses such as Christie’s and Sotheby’s have seen record-setting nephrite jade pieces. Many are antiques, so historic value adds to the value of the material itself. Top-quality and important imperial court-related pieces can compete with the prices of high-end jadeite jade.

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	Nephrite Auction Pieces Gallery

	Besides these major auction houses, there are quite a few others that specialize in modern jade items. This very special selling channel can only be found in China. The auction houses cater not only to rich consumers, but also to ordinary consumers and jade collectors.

	One of those auction houses is Beijing Boguan Auction House. Since its founding in 2006, Boguan has held more than 100 auctions with 28 different themes. Their focus is on modern jade carvings and jewelry. Many of the buyers are collectors at different levels and many are simply jade lovers. The most recent auction, held in Beijing on April 12, 2015, realized total sales of about US$1 million. These auctions provide a platform to connect master carvers with ordinary buyers and collectors.

You do not have to be incredibly rich to bid in an auction. This auction, hosted by Beijing Boguan Auction House, was held on the ground floor of a big shopping mall in Beijing. Buyers are very passionate about this type of auction. Courtesy Beijing Boguan Auction House.

THE FUTURE

	Kirk Makepeace predicts a promising future for nephrite mining in British Columbia. His nephrite business involves his entire family. The most important factor, in his opinion, is the growing appreciation for nephrite and the growing desire to keep rough prices high enough to offset the increasing cost of mining. Although environmental regulations for mining gemstones are getting stricter he does not see them as a challenge for his operation.

	On the other side of the globe, the Chinese government also places strict regulations on mining nephrite to keep the resource sustainable and the mines environmentally friendly. Siberian miners also realize the economic value of their nephrite resources and have already started to stabilize production, trying to get the best benefit for local development.

After more than 30 years, Kirk Makepeace is still excited by his nephrite jade business. This passion has been passed on to his daughter Nikki, a GIA graduate who now shares duties with her dad. The entire family is involved in the business and they have confidence in the potential of this gem material. Courtesy Jade West Group

	However, the bureaucratic requirements are increasingly time-consuming and expensive. Costs of labor, fuel, and transportation are also constantly on the rise. These are the problems that all source areas are facing. The rise in revenue from mining nephrite must continue as operations go deeper into the mountains.

Siberian miners have high expectations for their green nephrite resources. While never easy, mining has become harder and more competitive. They hope for a prosperous market in China and rising prices to help keep mining profitable. Courtesy Sibirgeology, Russia

	Nephrite jade has been appreciated in the Orient, especially China, for thousands of years. Many people are working hard to preserve jade culture and to pass it on to future generations. To support this heritage, a stable supply is necessary. For this reason, limited production of nice green nephrite has forced the Chinese market to move past its traditions and embrace supplies from Canada and Russia.

Buyers have become increasingly interested in auctions of jade carvings and jewelry. Consumer support is the main force driving the desire to keep the green nephrite road connected and well maintained. Courtesy Beijing Boguan Auction House

	At the same time, the quality of imported green nephrite has gradually given those sources their own growing reputations, winning consumers over. Chinese investors also go all over the globe to find new resources to fulfill domestic demand. With overseas materials coming in and Chinese material going out, the jade road formed over the past three decades will be well maintained and further developed as the Chinese market keeps growing. Source: GIA @topic:12


Title: Rare Faceted Hexagonite Abstract: Figure 1. This 3.27 ct pinkish purple hexagonite is the largest example examined by the authors. Photo by Robert Weldon; courtesy of Vance Gems.

A saturated pinkish purple hexagonite (figure 1) was recently examined at the Carlsbad laboratory. Standard gemological testing revealed a refractive index of 1.599–1.629 and a specific gravity of 2.97 obtained hydrostatically. Microscopic examination showed needle-like inclusions and iridescent cleavage cracks (figure 2).

Figure 2. Iridescent cleavage cracks and needle-like structures were present in the faceted hexagonite. Photomicrograph by Nathan Renfro; field of view 3.50 mm.
When observed with a dichroscope, pleochroic colors of pink, orangy pink, and violet were observed. These results were consistent with the mineral tremolite. The pinkish purple variety of tremolite is recognized as hexagonite, which owes its color to manganese. Hexagonite was once thought to be a hexagonal form of tremolite, which is how its name was derived, but was later confirmed to be monoclinic (Summer 1985 Gem News International, p. 110).

This particular stone was faceted by Bill Vance of Vance Gems, who sourced the rough that was reportedly from the original type locality, the Balmat-Edwards zinc mining district in St. Lawrence County, New York. Hexagonite is also found at the town of Fowler in St. Lawrence County. The saturated pinkish purple color and large size make this rare stone an exceptional example of this material. While very few faceted hexagonite gems have been tested at GIA, this 3.27 ct stone is the largest one examined by the authors. Source: GIA @topic:2


Title: Beryllium-Diffused and Lead Glass–Filled Orange Sapphire Abstract: Figure 1. This 4.25 ct orange sapphire was submitted for a colored stone identification report. Photo by Robison McMurtry.

              The Carlsbad laboratory recently received a 4.25 ct transparent orange oval mixed-cut stone (figure 1) for a colored stone identification report. Standard gemological testing established the following properties: RI—1.762 to 1.770; birefringence—0.008; optic sign—uniaxial negative; pleochroism—strong orange and very light yellow; and SG—3.98. All of these properties are consistent with both natural and synthetic sapphire.

Under magnification, the most distinctive internal characteristic was the presence of numerous fractures partially healed by glassy flux-like droplets. Some had a wispy veil and fingerprint-like appearance. One fracture with large healed areas showed a strong flash effect, which appeared greenish blue under brightfield illumination (figure 2, left) and orange-red under darkfield illumination (figure 2, center) when rotating the stone to another direction. Under diffused lighting, the outline of the large partially healed areas stood out clearly (figure 2, right). The flash effect indicates that the fracture was healed using a material with a high refractive index, possibly lead glass (S. F. McClure et al., “Identification and durability of lead glass–filled rubies,” Spring 2006 G&G, pp. 22–34).

Figure 2. Under brightfield illumination, the large healed fracture showed a greenish blue flash effect (left). Under darkfield illumination, the same fracture showed an orange-red flash effect (center). Under diffused lighting (right), the outline of the fracture became distinct. Photos by Ziyin Sun; field of view 3.45 mm.
Heat-treated sapphires submitted to GIA are routinely checked using advanced analytical tools. Energy-dispersive X-ray fluorescence (EDXRF) analysis was performed on the table facet where the large healed fracture with flash effect was located. The presence of Pb was clearly detected, indicating the filler was lead glass. Laser ablation–inductively coupled plasma–mass spectrometry (LA-ICP-MS) was used to confirm the stone’s natural trace-element chemistry and detect the beryllium-diffusion treatment. Beryllium was present in all laser ablation spots, but analysis of the partially healed fractures revealed high Pb content in addition to Be. In one spot, both high Be (156 ppmw) and Pb (23,300 ppmw) were present, which provided some possible insight into the treatment process.

Corundum selected for lead-glass filling usually goes through a two-step process. The material is heated at temperatures from 900° to 1400°C to remove the impurities in fissures, followed by another heating at 900° to 1000°C in the presence of a lead-glass mixture to fill the fractures (V. Pardieu, “Lead glass filled/repaired rubies,” Asian Institute of Gemological Sciences Gem Testing Laboratory, 2005, http://fieldgemology.org/Ruby_lead_glass_treatment). Beryllium diffusion requires a temperature range from 1800° to 1850°C, close to corundum’s melting temperature of 2045°C, which requires a special resistance furnace (J. L. Emmett et al., “Beryllium diffusion of ruby and sapphire,” Summer 2003 G&G, pp. 84–135). If the stone had been filled first, the lead-glass filler likely would have melted and flowed out of the fractures during the beryllium diffusion treatment (McClure et al., 2006). It is unlikely that the Be diffusion and lead glass–filling treatments occurred simultaneously. Such a process has not been documented and would likely pose technical challenges, partly because the relatively high temperature required for the beryllium diffusion treatment would have outgassed much of the lead and caused serious toxic gas exposure.

The best possible explanation is that the stone was beryllium diffused at a high temperature to improve its color before being treated with lead glass at a lower temperature to improve its clarity. If some residue of the original Be treatment was left in a fracture that was later filled with lead glass, this could explain the correlation of high Be and high Pb in one of our LA-ICP-MS analyses.

GIA’s laboratories have identified numerous beryllium-diffused or lead glass–filled stones. That the two treatments were applied in a single sapphire is very rare. It is the first time such a stone has been examined by the GIA laboratory. Source: GIA @topic:3


Title: The Chemical Distinction of Natural from Synthetic Emeralds Abstract: The chemical characteristics of natural and synthetic emeralds were studied in order to identify differences that could be used to separate them from one another. Thirty-eight natural emeralds from 20 localities and 11 synthetic stones from six manufacturers (flux and hydrothermal growth processes) were analyzed by microprobe and X-ray fluorescence. The results revealed a complex collection of chemical constituents that reflect the different environments in which natural and synthetic emeralds form. The present study agrees with the limited number of analyses previously reported for both materials. Thus, a new method of distinguishing natural from synthetic emeralds is now available for use in gemology when more conventional methods prove inadequate. Source: GIA @topic:3


Title: Some Observations on the Treatment of Lavender Jadeite Abstract: The separation of naturally colored lavender jadeite from color-treated material is a problem that has long plagued gemologists. One theory is that the dyeing agents being used are of an organic nature. If this is true, they should break down at elevated temperatures and lose their coloring ability. Naturally colored lavender jadeite, however, should retain its color and not bleach on heating. To investigate this theory, the author sawed 42 different specimens of lavender jadeite in half. One half of each specimen was heated while the other half was retained as a color control. Those stones that bleached on heating showed a strong orange fluorescence to long-wave ultraviolet radiation before heating and a moderate bluish-purple X-ray fluorescence both before and after heating. The control halves of those stones that retained their color when heated to as high as 1000°C fluoresced a very weak brownish red when exposed to long-wave ultraviolet radiation and a strong reddish purple to pink when exposed to X-ray radiation both before and after heating. Source: GIA @topic:11


Title: Update on Liberian Ruby Abstract: Figure 1. Ten corundum samples from the Lofa River in Weasua, Liberia. Photo by Shunsuke Nagai.
Liberian rubies were reported more than a decade ago (L. Kiefert and M. Douman, “Ruby from Liberia,” Summer 2011 G&G, p. 138). These rubies were found in two diamond mines located along the Mano River and in Nimba Province close to the Guinean border. GIA’s Tokyo laboratory recently received 10 Liberian corundum samples (figure 1) from the Japan-based NGO Diamonds for Peace. These samples were collected at Weasua, Liberia, the same locality recently reported in G&G (Spring 2023 GNI, pp. 149–150).
Most of the rough corundum pebbles recovered from Weasua showed weakly saturated purplish red, pink, pale yellow, and green colors; most fall in the color range of sapphire, except for a few red ones. Three of the ruby samples—11.65 ct purplish red (A), 6.52 ct dark purplish red (B), and 5.37 ct light purplish red (C)—were cut and polished for observation and advanced testing. Standard gemological testing yielded a refractive index of 1.762–1.770, a uniaxial interference pattern, and a hydrostatic specific gravity of 3.85–3.99. Except for the specific gravity, which is slightly low presumably due to the inclusions, the gemological characteristics were consistent with corundum.

Figure 2. Sample A shows strong two-direction lamellar twinning structures (top left) and contains numerous reflective inclusions near the rim (top right). Both photos are under fiber-optic illumination; the light source of the top right photo is in a specific direction to show the reflective inclusions. Photomicrographs by Yuxiao Li; field of view 19.5 mm. The plot at the bottom shows the minor/trace element concentrations of each spot. The spot position is shown in the top right photo.

Figure 3. Black inclusions, identified as vonsenite by Raman spectroscopy, were observed with twinning planes (left) and reflective particles aligned in three directions with fine needles (right). Photomicrographs by Yuxiao Li; fields of view 2.4 mm (left) and 2.9 mm (right).
The rounded surfaces of the rough stones suggested weathering. Most were semitransparent to translucent, heavily included, and displayed lamellar twinning structures in two orientations (figure 2). The twinning planes were filled with orange secondary minerals. Other internal features included irregularly shaped reflective particles aligned in three directions, iridescent small particles, and fine needles (figure 3). Sample A showed a less-included core and particle-rich rim, and sample B was heavily included with large whitish aggregate inclusions and some small black minerals along the twinning planes. These black minerals were identified by Raman spectroscopy as vonsenite (Fe2+2Fe3+(BO3)O2).

Laser ablation–inductively coupled plasma–mass spectrometry (LA-ICP-MS) was carried out to analyze trace element compositions. On sample A, we measured nine spots from center to edge. The rim area (spots 7–9) yielded higher iron and titanium, and similar levels of magnesium, vanadium, and gallium compared with the less-included core area (spots 1–6) (figure 2). We measured three spots on each of the remaining two samples. The results are presented in table 1, showing the wide range of concentrations of titanium, vanadium, iron, and gallium. (Spot 1 of sample B shows high titanium (84.3 ppma) with zirconium (0.054 ppma), likely caused by the contamination of small inclusions.)
Kongsomart et al. (Winter 2017 GNI, pp. 472–473) summarized the trace element concentrations in rubies from East African deposits. Samples A and C of the Liberian rubies in this study showed trace element concentrations similar to those from Mozambique. Sample B had a high gallium concentration, overlapping with rubies from the Zahamena deposit in Madagascar. Considering the wide range of trace element concentrations of Liberian rubies and those from East African deposits, these chemistry components are not helpful in separating the Liberian ruby from other origins. The ruby samples from these East African origins are less included than the Liberian samples in this study. For identification services, we are able to determine the origin not only by trace elements but also by microscopic observations (A.C. Palke et al., “Geographic origin determination of ruby,” Winter 2019 G&G, pp. 580–613). If it is necessary to separate Liberian rubies from other highly included low-quality rubies, comprehensive study on such included samples is needed.
Recently, some low-quality rubies reportedly mined from Guinea have been sold on the market. These materials are often heat treated and filled with lead glass, with some cabochons displaying six-rayed asterism after treatment. Both rough samples of Guinean ruby in the GIA colored stone reference collection and the studied Liberian rubies show a classic weathered “barrel” shape, semitransparent to translucent transparency, pinkish color, and most are heavily included. Given that the deposit of Guinea ruby is located upstream, north of Liberia, these rubies presumably originated from the same or closely related geological condition. With proper treatment, Liberian rubies could show asterism and be used as jewelry material. Source: GIA @topic:1


Title: Unique Drilled Emerald Abstract: Figure 1. This 3.39 ct emerald (8.91 × 8.87 × 7.61 mm) is moderately clarity enhanced, obscuring two drill holes (not visible in this photo). Photo by Sood Oil (Judy) Chia.

	A 3.39 ct emerald, as confirmed by standard gemological testing, was received by the New York lab (figure 1). At first glance it appeared to be a typical emerald with moderate clarity enhancement. It was categorized as F2, indicating that the fracturing present in the stone had a noticeable but not significant effect on the face-up appearance. Further microscopic examination of the pavilion revealed two prominent drill holes filled with a resin and emerald fragments (figure 2). The resin displayed a blue and yellow flash effect, and gas bubbles trapped in the resin were also present (figure 3). The filler had much higher relief than the emerald host and was clearly visible under reflected light due to the difference in luster between the two materials (figure 4).

Figure 2. With microscopic examination, the circular outline of the drill hole is apparent on the pavilion facet of the emerald. Photo by Edyta J. Banasiak; field of view 4.08 mm.

Figure 3. This drill hole shows a blue and orange flash effect along the interface between the emerald and the resin filler. Photo by Edyta J. Banasiak; field of view 3.57 mm.

	The question arose as to why such a treatment would be performed on this stone. Microscopic observation did not yield any clues. One hypothesis would be that eye-visible inclusions were removed by drilling, analogous to the laser-drilling treatment well known in diamonds. Assuming this theory is true, the “enhancement” actually significantly reduced the value of this good-quality emerald. We concluded that the stone contained a resinous material in the drill holes along with emerald fragments. This was the first time GIA’s New York lab had witnessed this type of enhancement in an emerald.

Figure 4. Examination of the drill hole in reflected light shows an emerald fragment intentionally placed in the opening, presumably to conceal the hole. Note the luster difference between the emerald and the resin filler. Photo by Edyta J. Banasiak; field of view 3.57 mm. Source: GIA @topic:3


Title: Flashes and Flames inEthiopian Opal Abstract: Figure 1. This 2.68 ct opal displayed play-of-color when viewed face-up (left) and flame-like chatoyancy on its slightly domed base (right). A more pronounced dome might have had the effect of sharpening the sheen into a cat’s eye. Photos by Kevin Schumacher.

	The relatively new source for precious opal located in Ethiopia’s Wollo Province produces material with vibrant play-of-color and occasionally with interesting inclusions. A recently examined 2.68 ct cabochon contained a scattering of octahedral metal sulfide inclusions (relatively common in Ethiopian opal) along with an unusual combination of optical phenomena: play-of-color and chatoyancy. Face-up, the stone showed the typical flashes of colors one would expect in precious opal (figure 1, left). However, the back of this cabochon contained an interesting structure that produced a sheen-like chatoyancy over its slightly rounded surface (figure 1, right). This chatoyant zone was strikingly similar to the flame structure seen in some non-nacreous pearls, which is produced by an intricate structure of aragonite crystal laths (figure 2). In the case of this opal, the flame-like structure’s cause remains an enigma, though it could be due to the structural influence of a preexisting fibrous mineral replaced by opal. Unfortunately, Raman analysis was unable to detect any presence of another mineral phase in the chatoyant area, so the exact cause of chatoyancy is still unknown.

	Figure 2. The fibrous nature of the opal’s unusual chatoyant zone is clearly revealed, along with the numerous minute octahedral black metal sulfide crystals that are a common inclusion in opal from Wollo. Oblique fiber-optic illumination. Photomicrograph by Nathan Renfro; field of view 2.73 mm.

	Chatoyancy is not unheard of in opal, though it is quite rare in precious material. Cat’s-eye common opal from Tanzania owes its optical effect to arrays of parallel needles, while the asterism and chatoyancy unique to the precious opal of Spencer, Idaho, are due to the arrangement of the same silica micro-spherules responsible for its play-of-color. At least one cat’s-eye precious opal was observed to even “wink” at the viewer when viewed with opposing lighting (Summer 2003 Lab Notes, p. 148). This Ethiopian opal cabochon joins the rarefied group of chatoyant precious opal with its unusual phenomenal display of flashes and flames. Source: GIA @topic:11


Title: Tourmaline Quality Factors Abstract: This 3.28-carat Paraíba tourmaline's vivid violetish blue hue rivals the finest sapphires. Because of this tourmaline's rarity, its per-carat price is also likely to rival the price of fine sapphire.

Color
One of tourmaline’s most sought-after and generally available colors is the pink/red variety known in the trade as rubellite.

	Tourmaline's hue and depth of color can approach the range of ruby and pink sapphire. This 8.16-carat cushion-shaped rubellite and 10.78-carat emerald cut pink tourmaline are superb examples.
Green tourmaline’s pastel hues provide the market with pleasing alternatives to the deep, rich hue of emerald and the softer green of peridot.  At their best, green tourmalines are transparent, brilliant, and clean, with attractive bluish green hues.

Most green tourmalines are strongly pleochroic. Stones that show attractive colors in both directions—such as bright green in one and blue in another—are the most valuable.

Chrome tourmaline gems offer hues that are more saturated than most green tourmalines. Chrome tourmaline can be a lower-priced alternative to tsavorite or emerald. Both these gems are rare in sizes above two carats, but it’s not hard to find chrome tourmaline in sizes up to five carats. And, while tourmaline can’t match tsavorite’s luster or brilliance, it’s far less expensive than a tsavorite of equivalent size and quality.

Dark-toned stones—which are more common in the marketplace—aren’t very attractive. Some absorb light so intensely that they appear almost black from certain directions. Cutters typically fashion these stones with the table parallel to the length of the crystal. Gems cut this way might show a less attractive brownish or yellowish color through the crown. Dealers frequently describe these gems as “oily” or “olive” green. Their prices are much lower than the prices for fine green tourmaline or brighter bluish green tourmaline.

	This 11.47-carat cushion-shape from Landanai, Tanzania, is a classic example of chrome tourmaline. Its high clarity, medium-dark tone, and strong green hue make it highly desirable.

	This 8.76-carat emerald cut tourmaline’s medium tone and strongly saturated, slightly yellowish green hue make it very marketable.

	High clarity, medium-light tone, and strongly saturated bluish green hue are the hallmarks of this 5.43-carat emerald cut tourmaline from Tanzania.
Blue tourmaline can range in tone from light to dark. The hue is often modified by green so you can have a blue color with just a little bit of green modifying color or a color that is very greenish but still blue. Some tourmalines have an even amount of green and blue to the color. Like green tourmaline the blue colors can be strong and vivid or less saturated and grayish.

	This 1.80-carat rectangular step cut tourmaline from Russia is medium light in tone and has a slightly greenish blue hue with moderately strong saturation. This is a noteworthy combination for a blue tourmaline.

	This 9.91-carat Afghan tourmaline hovers on the boundary between green and blue hues. Its high clarity and medium tone give it a pleasing appearance.

	This 5.19-carat medium-dark, very strongly greenish blue emerald-cut tourmaline is from Namibia.
Since it was discovered in the late 1980s, Paraíba tourmaline’s striking neon blues and greens have electrified the gem world. The gem’s unique, vivid coloring instantly set it apart from other tourmalines. Initial worldwide reception to the gem was wild, especially in Japan, where demand for fine-colored stones was insatiable.

Prices for this exotic newcomer—especially top quality in sizes between 3.00 and 5.00 carats—climbed rapidly to over $10,000 per carat. No tourmaline—even prized rubellite reds and chrome greens—had ever achieved such heights in value. Paraíba tourmaline’s rarity undoubtedly contributes to its high prices.

	Fashioned Tourmaline can be found in large sizes. This magnificent stone weighs 45.31 carats and boasts natural, untreated color. Photo: Katharina Mint Ring © 2011 Fabergé Ltd.
The gem is an elbaite tourmaline that comes from one area of Paraíba state in Brazil’s northeast corner. Like many other Brazilian elbaites, Paraíba tourmaline forms in pegmatite. But researchers believe that its crystals form under very unusual conditions, with large amounts of trace elements like manganese and copper, which causes its color. Paraíba tourmaline is unusual because, although copper colors some other gems—notably turquoise—it’s not a coloring agent in any other tourmaline.

In some specimens, there’s so much copper that inclusions of native copper—almost pure metal—highlight the gem’s interior. Scientists speculate that the native copper inclusions took shape in the early stages of cooling, after the gems started to crystallize.

Paraíba tourmalines appear in a range of greenish blue, bluish green, green, blue, and violet hues. Although buyers covet all these colors, blue and violet have the most appeal. Dealers use a number of names to try to capture the extraordinary quality of Paraíba tourmaline’s colors. Besides neon, they use terms like “electric,” “turquoise,” “sapphire,” or “tanzanite” blue, and “mint” green.

	The Paraíba deposit revealed a range of new tourmaline colors unrivaled for their strongly saturated hues and light to medium tones. Representing the color range are a 2.59-carat turquoise-blue triangle cut, a 3.28-carat electric-blue pear shape, and a 3.68-carat green pear shape.
Overall, prices for the best Paraíba tourmalines easily surpass other tourmalines due to their more attractive hues, higher color saturation, and greater rarity. A direct comparison with other tourmalines makes the difference obvious. Compared to any other green tourmaline, for example, a green Paraíba tourmaline will have a more saturated hue and lighter tone.

Because of the rough’s high value, Paraíba tourmalines are almost always custom cut. They’re usually faceted into brilliant cuts, commonly pear and oval shapes. You’ll rarely see Paraíba tourmaline in sizes bigger than one carat. With Paraíba, however, color is the key factor, not size. So if a dealer has to choose between a larger stone and a more vividly colored one—all other factors being equal—the gem with the better color is a better choice.

Copper-bearing tourmalines that resemble the vibrant, intense colors of the gems found in Brazil’s Paraíba region have also been found in other parts of the world. An article in the Spring 2008 issue of GIA’s Gems & Gemology scientific journal describes the copper-bearing gems of Mozambique. Nigeria has been a source of these striking gems as well.

During Paraíba tourmaline’s brief history, dealers have often resigned themselves to the gem’s extreme scarcity. However, new discoveries elsewhere in Brazil and eastern Africa present the possibility that viable, commercial sources of this rare copper-bearing tourmaline might one day supply the trade with more material. Unfortunately, the new sources also raise questions about the use of the term Paraíba to name these treasured gems.

	The discovery of significant copper-bearing tourmaline deposits in Mozambique
	increased availability and broadened the appeal for this gem. This 14.53-carat heated
	gem is mounted in a striking pendant with black and red spinel, yellow sapphire, tsavorite,
	and diamond accents. - Courtesy Carley McGee-Boehm, Carley Jewels

	Sources in Nigeria produce a vivid array of copper-bearing tourmalines. These stones range in size from 0.31 carat to 1.04 carats. - Courtesy Barker & Co.
Watermelon, bicolor, and multicolored zoning occurs when the trace elements change in concentration or composition during a crystal’s growth. Liddicoatite can show striking and complex zoning, and gems are often fashioned to showcase exotic color combinations. Gemologists describe these tourmalines as parti-colored.

	This 11.21-carat bicolor tourmaline is a supreme example of both the gem material and the cutter's art. The stone has intense colors, a clean junction between the zones, and the highest clarity. - Lydia Dyer, gem courtesy of John Dyer & Co.

	This Brazilian crystal is a typical watermelon tourmaline, with a pink core surrounded
	by a thin green skin. The colors are best shown in thin slices, which are well suited to
	one-of-a-kind jewelry pieces. - Courtesy Brasgemas
Sometimes tourmalines are color-zoned across the length of the crystal: A crystal that starts off as pink might end up with a green tip. Or they can be zoned parallel to their length, so that a red crystal might end up with a green overgrowth. Dealers call these watermelon tourmalines because their colors resemble the rind and flesh of that fruit. Designers sometimes exploit the look of watermelon tourmaline by setting slices of the crystal rather than faceting the rough.

Clarity
Colored tourmalines grow in an environment rich in liquids, and some of those liquids are often captured as inclusions during crystal growth. The most typical inclusions resemble thread-like cavities that run parallel to the length of the crystal. Under magnification, you can see that they’re filled with liquid or gas bubbles. Growth tubes—long hollow tubes often capped with minute mineral crystals—are also common tourmaline inclusions. If they’re numerous enough, and the rough is correctly cut, they can cause a cat’s-eye.

	The gems in this remarkable suite of cat’s-eye tourmalines are all from Brazil. Inclusions
	cause the cat’s eye effect and add value. - © GIA and Harold & Erica Van Pelt
Dealers usually tolerate red tourmalines with some eye-visible inclusions as long as the color is strong and attractive. Inclusions that reach the surface interfere with luster and polish and make gems harder to sell. And although liquid inclusions are less visible in stones of intense color, stones with prominent whitish inclusions—no matter how vibrant the color—are undesirable.

Inclusions are much more visible in gems with light tone and low saturation. Since these stones don’t have strong and attractive color to compensate for the inclusions, most buyers reject the ones with eye-visible inclusions. Many included tourmalines with good color are cut as cabochons to emphasize the color and minimize the appearance of the inclusions.

It’s not unusual for pink and red tourmalines to have eye-visible inclusions. Unless their size or the number of the inclusions is distracting, knowledgeable consumers consider the color to be the dominant value factor. Green tourmalines are expected to be free of eye-visible inclusions so distracting inclusions can lower the value of the green gems. For the other colors, tourmalines with no eye-visible inclusions are more valuable than those with inclusions that can be seen. The more visible any inclusions are, the more the value drops.

Cut
The elongated shape of many tourmaline crystals has a direct impact on the finished gem’s shape and proportions. As a result, there are many narrow, non-standard sizes available. Although some are very attractive, many gem buyers prefer stones with standard dimensions because they’re easier to set in standard mountings.

	Jewelry designers create custom mountings to accommodate the shape of fashioned tourmalines. - © GIA & Tino Hammid, courtesy Chris Almquist
Cutters often fashion tourmalines as long rectangles. Making the cut parallel to the length of the rough crystal helps to reduce waste. But cutters also have to consider tourmaline’s optical properties.

Tourmaline is strongly pleochroic, which means that it can show different colors in different crystal directions. One of tourmaline’s pleochroic colors is typically much darker than the other. In addition, many tourmalines absorb more light down the length of the crystal than across it. So a crystal that appears pale green across its length can be very dark green—sometimes almost black—when you look down its length.

Rather than cutting every tourmaline lengthwise, many cutters orient a fashioned gem based on its depth of color. To darken pale rough, they might orient a gem’s table so it’s perpendicular to the crystal’s length. To lighten dark rough, they orient a finished gem’s table so it’s parallel to the crystal’s length.

Carat Weight
Fashioned tourmalines in larger sizes rise considerably in per-carat price. Even though specimens can reach spectacular sizes, these are rare. Availability drops and prices rise sharply for facet-quality rough material. For fashioned gems of similar color and clarity, the price per carat generally increases as the gems pass the five-carat milestone.

	Large tourmaline crystals are often fashioned by gem sculptors into special pieces for clients looking for the unusual. Renowned Idar-Oberstein gem cutter Bernd Munsteiner fashioned this 11.18-carat blue-green gem in his unique style. Source: GIA @topic:1


Title: Blue Sapphire Reportedly from Badakhshan, Afghanistan Abstract: Figure 1. These blue and purplish sapphires are reportedly from a new deposit near Khash in Badakhshan Province, Afghanistan. The largest stone weighs 19.6 ct and measures 19.2 × 13.9 mm. Photo by Lhapsin Nillapat.

Recently, Habib Khan (Royal Gems Stone, Bangkok) donated a parcel of more than 40 rough sapphires to the GIA laboratory in Bangkok. Mr. Khan reported that they were mined from a new deposit in Badakhshan Province of northeastern Afghanistan. A few days later, Kamran Wahidy from the city of Fayzabad informed author VP of a new sapphire deposit near Khash in Badakhshan. This site produces material similar to the stones presented by Mr. Khan. Previous discoveries of corundum around Khash have been reported (Fall 2007 GNI, pp. 263−265; Winter 2010 GNI, pp. 319−320).  The samples (see figure 1) were blue, purplish, or near-colorless. The rough sapphires ranged from 0.9 to 19.6 ct and were transparent to translucent. Standard gemological testing revealed an RI of 1.760−1.768 and an SG of 3.71−3.98. The wide range in SG can be explained by the large pieces of lighter matrix attached to some of the corundum samples. The stones displayed weak orange to inert fluorescence under long-wave UV and were inert under short-wave UV.  All samples were originally covered with a thick, dark greenish black skin that was removed to reveal the blue sapphire inside. Most samples still had some of this skin attached. The skin contained dark green spinel, phlogopite, chlorite, feldspar, amphibole, and tourmaline, which were identified by Raman spectroscopy.  Flat negative crystal fingerprints were commonly seen; some contained CO2 bubbles and diaspore fibers that became visible at 60× magnification. The samples displayed ladder- or dust-like inclusions similar to those seen in sapphires from Kashmir (figure 2; see H.A. Hänni, “A contribution to distinguishing characteristics of sapphire from Kashmir,” Journal of Gemmology, Vol. 22, No. 2, 1990, pp. 67−75).

Figure 2. Inclusion scenes in the Badakhshan sapphire. Left: Ladder-like inclusions under darkfield illumination; field of view 2.7 mm. Right: Negative crystals with CO2 bubbles; field of view 1.8 mm. Bottom: Crystal inclusions of amphibole (green circles) and mica (white circles); field of view 2.4 mm. Photomicrographs by Charuwan Khowpong (left) and Victoria Raynaud (right and bottom).
Crystal inclusions were identified (using Raman spectroscopy and the RRUFF reference database) as apatite, amphibole, mica, diaspore, chlorite, tourmaline, feldspar, and spinel. We also observed unidentified clusters of tiny black crystals and crystals that might have been epidote or allanite. FTIR spectroscopy revealed the presence of boehmite, kaolinite, and a peak at 3161 cm−1. LA-ICP-MS showed an iron content between 154 and 402 ppma, while gallium ranged from 7 to 11 ppma.  If confirmed, the discovery of a new blue sapphire deposit near Khash could be interesting for the gem trade in Afghanistan. However, this new material represents a true challenge for gemologists working on origin determination, as its inclusion scene is, in some aspects, very similar to those in sapphires from Kashmir. Source: GIA @topic:3


Title: The Foldscope and Its Gemological Applications Abstract: Figure 1. A fully assembled Foldscope measures approximately 7 × 2.5 in. A toggled LED light source is tucked into tabs on the back, and the bottom center slit accommodates standard glass microscope slides. Photo by Kate Pleatman.

              The Prakash Lab of Stanford University, a small team of graduate students led by bioengineering professor Manu Prakash, has created a portable paper microscope called the Foldscope. Originally conceived for disease detection in remote areas, it was later expanded for educational use. The concept of the Foldscope won a $100,000 grant from the Gates Foundation in 2012 and a $50,000 first prize from the 2014 Moore Foundation Science Play and Research Kit Competition, which challenges participants to reinvent scientific tools of the past to attract a new generation of scholars. Speaking at the annual TED Conference in March 2014, Dr. Prakash announced that the concept was prototyped, functional, and could be manufactured for less than $1 each.

Submissions were accepted for a beta test group (now closed) named the “10,000 Microscope Project.” The goal was to get a Foldscope in the hands of 10,000 users worldwide, in medical and non-medical fields. The project requested users who understood microscopy and agreed to write detailed scientific studies based on their own research, to be collected and published to show the variety of potential uses. Seeing a major application in field gemology, this author requested and received a Foldscope.

Beta testers received Foldscope components and instructions in December 2014. The body is made of a material more like plastic than paper, to prevent tearing. Pieces are punched out of perforated sheets and assembled like origami (figure 1). The kit also contained interchangeable low-magnification (140×) and high-magnification (400×) lenses, a 3V LED toggled light source, and a surprise: a coupler to connect to a cell phone for photomicrography. Due to its complexity, assembling the Foldscope may take an hour or two. The device was ingeniously constructed, but would it work with gems?

Stones between 1 and 3 mm could be mounted onto glass slides for study. Larger stones were held with gem tweezers in the slide opening, to test whether the Foldscope would work with loose stones as well. Stones that were transparent and relatively small produced impressive results. The use of a binder clip to hold the slide or tweezers in place freed the hands to manipulate the focus more precisely. Focusing was the biggest obstacle, and late in the research the author inadvertently scratched a lens while trying to focus on a 1 mm corundum culet.

Figure 2. This photomicrograph of synthetic opal, taken using the high-magnification lens (400×), shows the characteristic cellular mosaic appearance. Photomicrograph by Kate Pleatman.
It was possible to clearly distinguish between natural and synthetic stones, because the magnification levels were exceptional (figures 2–4). Yet the small fixed size of the slide opening made it difficult to use with loose stones in tweezers, and gems more than 8 mm in depth could not pass enough light to view. Opaque material was not visible at all.

Figure 3. These fluid inclusions in quartz were taken using the Foldscope’s low-magnification lens (140×). Photomicrograph by Kate Pleatman.

Figure 4. These liquid inclusions in ruby are seen using the low-magnification lens (140×). Photomicrograph by Kate Pleatman.
Research details, photos, and feedback were sent to the Prakash Lab, along with design recommendations for making the device more ideal for gemological use. Suggestions included protection for the lens to prevent scratching and a larger gap for examining non-slide materials such as loose stones held with tweezers. An optional three- or four-inch fiber-optic light attachment would offer illumination from any angle, even for mounted stones. The Foldscope team has been very attentive to the feedback, although they have not committed to any alterations. Time will tell if the suggested modifications are feasible. No public release date or final price for the existing version has been announced. For more on this tool, visit www.foldscope.com. Source: GIA @topic:1


Title: Trapiche and More... Abstract: Colombia’s unique trapiche emeralds exert a fascination for many gemologists. In fine specimens, the combination of rich, gemmy green color with the six spokes’ geometry is visually arresting.

	In our lead article, we’re delighted to present a comprehensive paper on these intriguing gems by a team of researchers headed by Isabella Pignatelli and Gaston Giuliani. They review the geology of trapiche emerald, provide 3-D petrographic examination of their crystals along with spectroscopic and chemical analyses, and propose a new formation model informed by their recent work. We hope this paper will serve as the primary reference on these one-of-a-kind gems for many years to come. Take a look at our cover photo and decide whether trapiche is a gemological curiosity or an object of beauty in its own right.

	In our next paper, GIA’s Ulrika D’Haenens-Johansson and her coauthors investigate the gemological properties of colorless to near-colorless HPHT-grown synthetic diamonds produced specifically for gem use by a Russian firm, New Diamond Technology. Their analysis of 44 faceted samples ranging up to 5.11 ct provides convincing evidence of the quality improvements—and increased size—of synthetics grown by this method.

		A gemological curiosity or an object of beauty in its own right?

	Meanwhile, Lesotho’s Letšeng-la-Terae mine is currently enjoying a renaissance. Rising prices for large, high-quality diamonds have overcome the twin challenges of this unique mine’s remote location and low ore grade. In our third article, GIA’s Russell Shor and Robert Weldon and their co-authors profile Letšeng to explain how the current owners have adapted their operations to promote recovery of the mine’s biggest gems and increase profitability. Coauthors Bram Janse, Christopher “Mike” Breeding, and Steven Shirey offer insight into this mine’s geology, its location on the Kaapvaal craton, and the distinctive characteristics of its diamonds.

	Next, Zemin Luo, Mingxing Yang, and Andy Shen from the China University of Geosciences in Wuhan apply a statistical analysis method based on linear discriminant analysis (LDA) and LA-ICP-MS trace-element data to the provenance of dolomite-related white nephrite. The authors demonstrate the technique’s high accuracy and potential for origin determination with many other gems.

	We hope you enjoy our second Micro-World column. We had a fantastic response to the first installment and are extremely pleased to welcome several new contributors. We also want to thank our Lab Notes and Gem News International (GNI) contributors—these sections always refresh me with their diversity.

	Finally, I’d like to welcome two new editors to our GNI section: Gagan Choudhary of the Gem Testing Laboratory in Jaipur, India, and GIA’s own Dr. Mike Breeding—we thank them for their commitment and participation.

	Welcome to our Fall issue! Source: GIA @topic:1


Title: Blue Cat's-Eye Apatite Abstract: Figure 1. This 12.50 ct neon blue cat’s-eye apatite is from Brazil. Courtesy of Duarte & Bastos Ltd. Photo by Eric Welch.

              Apatite is a group of minerals belonging to the hexagonal crystal system with the chemical formula of Ca5(PO4)3(F,Cl,OH). It has a variety of colors and is usually transparent to translucent. The most common apatite is the fluorine-rich type, known as fluorapatite. Blue apatite is particularly rare and popular. Previous research indicates that due to the similarity between the optical absorption and emission spectra of natural blue apatite and synthetic compounds containing MnO43–, the blue color results from the substitution of PO43– with MnO43– (P.D. Johnson et al., “Apatite: Origin of blue color,” Science, Vol. 141, No. 3586, pp.1179–1180). Chatoyancy is a very common phenomenon in apatite crystals with green or yellow bodycolors. Deep blue apatite with a cat’s-eye effect, however, is very rare.

At this year’s GJX show in Tucson, Duarte & Bastos Ltd. from Teófilo Otoni, Brazil, exhibited a 12.50 ct intense blue cat’s-eye apatite cabochon (figure 1). The stone was said to be from Brazil. It had a neon blue bodycolor and a very sharp eye seen with a spot light source. Further research is needed to verify the color origin of this stone. Source: GIA @topic:2


Title: Zircon Description Abstract: Zircon comes in a wide variety of colors.

                      Colorless zircon is well known for its brilliance and flashes of multicolored light, called fire. These two zircon properties are close enough to the properties of diamond to account for centuries of confusion between the two gems.

Zircon occurs in an array of colors. Its wide and varied palette of yellow, green, red, reddish brown, and blue hues makes it a favorite among collectors as well as informed consumers.

Zircon crystals grow in many different types of rock and possess a range of optical and physical properties.

Some zircons—usually green ones—display much lower values for these properties than others. Scientists have determined that the crystal structures of these gems were almost completely broken down by radioactive elements—often present in zircon as impurities—that damaged the gems’ crystal structure over long periods of geological time.

Some gemologists classify zircons into three types—high, intermediate, and low. A zircon’s classification depends on its properties, which are directly related to the amount of radiation-induced damage done to its crystal structure.

High or normal zircons have full crystal structures, with little or no damage from radioactive elements. As a result, they have the normal physical and optical properties associated with the mineral.

In intermediate or medium zircons, radioactive elements have caused some structural damage. They have physical and optical properties that are between high and low types.

Extensive crystal-structure damage from radioactive elements results in low zircons with much lower optical and physical properties. In extreme cases, they are practically amorphous, which means they lack an orderly crystal structure.

Virtually all the zircons used in jewelry are of the high type. Interestingly, radiation-induced crystal-structure breakdown can be reversed somewhat by heating zircon to high temperatures. High-temperature heat treatment repairs the stone’s damaged crystal structure. Source: GIA @topic:3


Title: A New Type of Synthetic Fire Opal: Mexifire Abstract: Synthetic opals have been produced and used in jewelry for more than three decades, and various imitation opals have been introduced in the trade. This article describes a new type of synthetic fire opal marketed as “Mexifire.” Some of the gemological properties of this synthetic are similar to those of natural fire opal. However, a low SG value (1.77) offers strong evidence of synthetic origin, and further indications are provided by a relatively low RI value (<1.40) and the presence of scattered pinpoints when examined with magnification. Source: GIA @topic:11


Title: Böhmite in Corundum Abstract: A large area of a foreign substance cut through on the surface of a ruby from the Montepuez area of Mozambique. This substance infilled not only this cavity but also many narrow fissures in the stone. Micro-Raman analysis identified it as böhmite. Darkfield + diffuse overhead illumination. Photomicrograph by Richard W. Hughes; field of view 3 mm.

Gemologists at Bangkok’s Lotus Gemology laboratory recently examined a large lot of rubies believed to originate from the Montepuez area of Mozambique. Microscopic examination confirmed that assessment. Many of these stones displayed features in their infrared spectra that are typical for böhmite, with a characteristic “twin peak” spectrum at ~3309 and 3089 cm–1 (figure 1).

Figure 1. “Twin peak” infrared spectrum of böhmite in the Mozambique ruby, with prominent peaks at ~3309 and 3089 cm–1.
One of the stones showed a large area cut through on a pavilion facet that appeared to be a foreign substance. A similar substance was seen in many of the fissures in the stone (top of page). Judicious use of the hot point under the microscope produced no reaction. We then moved to analyze the substance via micro-Raman. The result was böhmite, which neatly confirmed the results from the infrared spectrum.
Böhmite, AlO(OH), is a polymorph of diaspore. In corundum it is generally a secondary mineral, infilling surface-reaching openings after the host corundum has grown. Source: GIA @topic:2


Title: Purple Jadeite Rock Abstract: Figure 1. This 13.60 mm mottled purple bead consists primarily of jadeite and quartz. Photo by Robison McMurtry.

              The Carlsbad laboratory recently took in a semi-translucent mottled purple bead for identification. Under microscopic examination, the material displayed an aggregate structure composed of fibrous lavender grains with a brownish white component (figure 1). Reddish orange minerals and small needle-like brown crystals were also observed. A spot RI reading of 1.55 was obtained on most of the stone, with a few places giving a reading of 1.66. The bead had a hydrostatic SG of 2.99 and was inert to both long- and short-wave UV radiation.

Basic gemological testing was inconclusive, but Raman spectroscopy performed on the various components of the stone confirmed the lavender and white portions were a mixture of jadeite and quartz, while the reddish orange portions were cinnabar. Additional spots on the scattered needle-like inclusions matched aegerine, a sodic-ferric clinopyroxene (figure 2). In addition to Raman testing, an infrared (FTIR) spectrum was collected to confirm the stone was not polymer-impregnated (E. Fritsch et al., “Identification of bleached and polymer-impregnated jadeite,” Fall 1992 G&G, pp. 176–187; Spring 1994 Lab Notes, p. 43).

	Figure 2. Upon closer examination, the jadeite rock also contains reddish orange cinnabar and brown aegerine crystals. Photomicrograph by Nathan Renfro; magnified 30×.
Purple rock containing jadeite and quartz has been reported in the Bursa region of western Turkey (M. Hatipoǧlu et al., “Gem-quality Turkish purple jade: Geological and mineralogical characteristics,” Journal of African Earth Sciences, Vol. 63, 2012, pp. 48–61). To date, the composition of this material is unique to the area. It occurs as a metamorphic product in the contact zone between a large blueschist belt and a granodiorite stock. While neither mercury nor cinnabar (a mercury sulfide) is mentioned in the literature on purple jadeite rock, mercury mining in western Turkey has been reported (M. Yildiz and E.H. Bailey, “Mercury deposits in Turkey,” U.S. Geological Survey Bulletin 1456, 1978).

The presence of mercury deposits in the region makes it highly likely that cinnabar or other mercury-bearing minerals would occur in the purple jadeite rock, consistent with a Turkish origin, though the origin of this sample has not been confirmed. Because jadeite and aegerine are both sodic pyroxenes, their occurrence together is understandable.

Purplish jadeite rock is being used in the jewelry trade and fashioned into beads, cabochons, and carvings. Source: GIA @topic:11