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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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Blue Sapphires from the Baw Mar Mine in Mogok
Reports on the microscopic, chemical, and spectroscopic features that differentiate the high-quality Baw Mar sapphire from “classic” gem-quality Burmese sapphire.
Update on Sapphire Mining in Ilakaka-Sakaraha, Madagascar
Summer 2012 Gem News International
G&G Announces Most Valuable Article Awards
G&G announces the winners of the Dr. Edward J. Gübelin Most Valuable Article Awards for 2019.
Gem Localities of the 2000s
The past decade saw some impressive discoveries of diamonds and colored stones.
Gemstone Enhancement and its Detection in the 2000s
Advances in technology and increased demand for lower-priced gem materials contributed to the proliferation of new treatments throughout the first decade of the 2000s.
Purplish Pink Spinel from Tajikistan: Before and After Cutting
In November 2008, the Bangkok laboratory was fortunate to have an opportunity to briefly examine seven stones that the client had faceted from this parcel.
Ruby and Sapphire Production and Distribution: A Quarter Century of Change
During the past 25 years, the corundum market has been transformed from one of medium to high-priced gems to one that encompasses nearly all price ranges.
Rubies and Sapphires from Winza, Central Tanzania
Since late 2007, rubies and sapphires have been mined by hand methods from both eluvial and primary deposits at Winza in central Tanzania.
Beryllium Diffusion of Ruby and Sapphire
The heat treatment of corundum involving lattice diffusion of beryllium (Be) at temperatures over 1800°C has become a major issue in the gem trade.
Sapphires from Antsiranana Province, Northern Madagascar
Since 1996, large quantities of yellow to blue sapphires have been recovered from alluvial deposits derived from basaltic rocks in northern Madagascar.
The Separation of Natural from Synthetic Colorless Sapphire
Greater amounts of colorless sapphire—promoted primarily as diamond substitutes, but also as natural gemstones—have been seen in the gem market during the past decade.
