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Sapphire
The name “sapphire” can also apply to any corundum that’s not ruby red, another corundum variety.
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Tools
Research
Dual-Color Double Stars in Ruby, Sapphire, and Quartz: Cause and Historical Account
Examines a form of asterism comprising two six-rayed stars, one white and one that exhibits the stone’s bodycolor. Firsthand accounts and a survey of patent documents reveal that diffusion has been used to create or enhance this optical phenomenon in synthetic and possibly natural corundum since the 1950s.
Rubies and Sapphires from Snezhnoe, Tajikistan
This large marble-hosted occurrence in the Pamir Mountains is a potentially productive source of corundum, including ruby with a bright red color reminiscent of “pigeon’s blood” Burmese rubies.
Update on Rock Creek Sapphire Deposit
An overview of recently expanded sapphire production at the Gem Mountain mine near Philipsburg, Montana.
Romancing the Source: Sri Lanka
Accompany GIA field gemologists on a true gemstone mining adventure in Sri Lanka, “The Island of Jewels.” You’ll observe traditional gemstone mining techniques that are still in use today. Sri Lanka is a mining, cutting, and trading powerhouse.
Fine Corundum, Demantoid Garnet
Insight into the markets for ruby, sapphire, emerald, and other colored gems.
Rough Diamond Auctions: Sweeping Changes In Pricing and Distribution
Examines the growing percentage of rough diamonds being sold through auctions, a shift that has caused price volatility while opening up supply to more manufacturers and dealers.
Exceptional Pink to Red Diamonds: A Celebration of the 30th Argyle Diamond Tender
Describes the extremely rare polished pink diamonds from Australia’s Argyle mine that have been sold for 30 years through invitation-only tenders.
Study of the Blue Moon Diamond
Presents spectroscopic and phosphorescence data of the Blue Moon, a 12.03 ct Fancy Vivid blue diamond discovered at the historic Cullinan mine in early 2014.
A Preliminary Study on the Separation of Natural and Synthetic Emeralds Using Vibrational Spectroscopy
Reports preliminary findings—based on FTIR and Raman spectrometry of more than 300 samples—on distinguishing natural and synthetic emeralds using vibrational spectroscopy.
Mozambique: A Ruby Discovery for the 21st Century
Join GIA on location at the Montepuez ruby mine in Mozambique, the most important ruby discovery of this new century.
Sri Lanka: Expedition to the Island of Jewels
Offers a firsthand look at Sri Lanka’s mining, cutting, jewelry manufacturing, and retail sectors, where tradition and innovation converge.
