GEM LOCALITIES OF THE 1990S

1. GEM LOCALITIES OF THE 1990S Nanospintronics lab. Sung K. Lim

2. Introduction • During the 1990s, new finds of gems created interest and excitement among both jewelers and consumers. • Gem localities continue to intrigue consumers because they create an integral part of the romance and lore that are associated with gemstones, an opportunity to purchase a symbol of beauty and rarity from a remote land. This Article • Identify key localities discovered during the past decade. • Highlighting deposits that either attained or continued at commercial • levels of production during thes period. • Newer or less-explored localities that may have potential in the future Nanospintronics lab.

3. BERYL • Emerald -Columbia : Principal source of fine-quality emerald (Formation by crystallization form hydrothermal solutions) -Brazil, Africa : there was an abrupt decline. -Afghanistan, Pakistan : fine-quality emeralds of small size • Surface reaching fracture • Filled with oils and resins • Infilling Process • A decline in the overall damand • for emerald and price Nanospintronics lab.

4. Aquamarine • Numerous deposit in Brazil • Africa source(Nigeria, Mozambique, Zambia, Madagascar) • Other Beryl • Greenish yellow heliodor from the Ukraine(exhausted by the mid-1990s) • Red Beryl from Wah Wah Mountain in southern Utha (Trade name : Red Emerld) Nanospintronics lab.

5. Chrysoberyl • Major source : Sri Lanka(alluvial), Brazil(pegmatite) • New source 1. Tunduru region of southern Tanzania 2. Ural mountain in Russia(alexandrite) 3. Southern Madagascar(cat’s eye, alexandrite) 4. India(green cat’s-eye, alexandreite) Nanospintronics lab.

6. Corundum • Ruby • Southeast Asian countries 1. Myanmar 2. Cambodia 3. Thailand (decrease in the last) Mong Hsu area Millions of dollars worth of ruby Nanospintronics lab.

7. These rubies require heat treatment to remove their distinct blue core. • 10~30 ct faceted rubies. 4. India, Africa (cabochon-quality material) 5. Malawi, Russia, Nepal, Afghanistan, Pakistan, China . • Heat-treated ruby resulted in lower prices. • → Raise concerns about correct • identification and disclosure for gem dealer • and consumers Nanospintronics lab.

8. Sapphire • Much of the sapphire on the market : Thailand, Cambodia, Myanmar, Vietnam, Sri Langka) • Australia : Production was down by the end of the decade. • The Tunduru region and several areas in Madagascar emerged as the most important commercial sources of blue and pink sapphire. Nanospintronics lab.

9. Deposits near Ban Huai Sai in Laos produced primarily smaller, medium to dark blue sapphires. • The output of blue and fancy-color sapphires form Montana fluctuated during the middle of the decade. • The treatment of sapphires to improve their color and clarity remained a major industry in the 1990s. • Most heat-treated high-quality blue and pink sapphire came from Sri Lanka and More recently Madagascar. Nanospintronics lab.

10. Diamond • All of the traditional diamond sources remained productive in southern and central Africa. (the seafloor off the coasts of Namibia and South Africa / Northeastern part of south Africa) • After the breakup of the former Soviet Union, a period of uncertanty began in the early 1990s. (Yakutia) • Diminished financial resources → Open-pit operation to undergrounding mining Nanospintronics lab.

11. Very large quantities of mainly small brownish to yellow or near-colorless diamonds continued to be recovered from the Argyle mine in northern Australia. • One of the more exciting developments in recent years was the discovery of gem-quality diamonds in northern Canada. • Discovery of new diamond deposits has been aided by the use of high-technology exploration methods. • Distribution Changes and Branding • The possibility of a “multi-channel” distribution system. • It increase consumer awareness of their geographic origin. Nanospintronics lab.

12. Garnet • Known source : East Africa, India and Sri Lanka • Ekaterinburg area in Russia (Babrovka River valley, Karkodino) • East Africa(Rhodolite), Diakon(grossular-andradite), Madagascar(pyrope-spessartine, tsavorite), • Orange specssartine garnet(Namibia, Madagascar, Zambia) • Nigeria(larger and cleaner spessartines) • Tunduru region of south Tanzania, Lindi Province, Kenya Nanospintronics lab.

13. Jade • Northern Myanmar continued to be the sole commercial source.(green, lavender, white jadeite) • New jadeite deposit : Japan, Russia, southern Kazakhstan • Nephrite deposits : North America, China • As China continues its rapid economic development, it is likely that demand for both nephrite and jadeite fake will also increase in that marketplace. Nanospintronics lab.

14. Opal • Major source : Australian localities in New South Wales, Queensland, South Australia • Mexico and Brazil were important producers of “fire” opal and white opal. • Prices for black opal from Lightning Ridge, Australia, declined briefly due to the collapse of the Asian market, but subsequent demand from the strong U.S. market brought prices close to those in the early 1990s. Nanospintronics lab.

15. Peridot • Gem-quality olivine from the United State(Arizona), Myanmar, China • However, the discovery of significant quantities of rich green peridot from Pakistan(exceptional clarity and large size) created renewed enthusiasm for this gemstone. • During the decade, commercial quantities of small piece of peridot were recovered in Vietnam. Nanospintronics lab.

16. Quartz • Amethyst : Brazil, Uruguay, Tanzania, Namibia, Zambia • The market for natural amethyst has been undermined by the widespread infiltration of synthetic amethyst. • Most citrine : Brazil (Some is produced by the heat treatment of amethyst.) • Sporadic mining of ametrine from Bolivia continued in the early and mid 1990s, but the quantity and quality of the material declined at the end of the decade. Nanospintronics lab.

17. Spinel • Spinel remains overshadowed in the marketplace by other colored gems such as ruby and pink sapphire. • Traditional localities : Sri Lanka, Myanmar. • New source : Tunduru in southern Tansania and Ilakaka in Madagascar. → smaller stones in many pastel colors. • Spinel was also found in Vietnam as a byproduct of ruby and sapphire mining. Nanospintronics lab.

18. Tanzanite • The only commercial source of tanzanite : Tanzania • In 1990s, tanzanite approached emerald, ruby, and sapphire in popularity in the U.S. • Its single source, rich color and availability in larger sizes made this gemstone a mainstay in some jewelry stores • Tanzania also has produced the rarer green zoisite, which colored by chromium. Recent discoveries of transparent pink and bicolored -pink and yellow- zoisite may provide new insight into geology of the Tanzania. Nanospintronics lab.

19. Topaz • Source : Brazil, Nigeria, Pakistan, Sri Lanka, and the Russia • Pink-to-orange “Imperial” topaz enjoyed a rise in price throughtout the 1990s, due to controlled supply in Brazil and minimal production in Pakistan. • One dramatic development was the decline in demand for irradiated blue topaz, for which much near-colorless topaz had been mined in the 1980s. Natural-color topaz was not commercially available during the ‘90s. Nanospintronics lab.

20. Tourmaline • Source : Brazil, Nigeria, Zambia, Mozambique, Madagascar, Tanzania, Kenya, Afghanistan • The early 1990s : The bright blue, green, and purple tourmalines from Brazil due to very limited availability and high demand. • The mid 1990s : Enormous quantities of bicolored and brownish pink material • The last 1990s : Even latger quantities of attractive pink-to-red tourmaline from Nigeria. Nanospintronics lab.

21. Other gem materials • Sphene : Brazil, Madagascar • Scapolite : Myanmar, Sri Lanka, Tanzania, China • Iolite : Canada, India, Sri Lanka, Madagascar • Benitoite : California • Zircon : Australia, Southeast Asia, Sri Lanka, East Africa • Rhodochrosite : Colorado • Apatite : Madagascar Nanospintronics lab.

22. Conclusion • While for many gem materials most of the countries now considered important producers were identified by the 1970s, the discovery of new deposits within these countries, and even deposits in newly identified source countries, continued throughout the 1990s. • The Past decade witnessed some exciting developments for the gem and jewelry industry. • Sociopolitical conditions continued to play an important role in the 1990s • Environmental concerns continued to influence gem-mining. • Looking into the next decade, we can predict the continued expansion of gem production in East Africa, Madagascar, and Southeast Asia, while Brazil and Myanmar remain important sources. Nanospintronics lab.