Inclusions in Natural, Synthetic, and Treated Ruby
Provides a visual guide to the internal features of natural, synthetic, and treated rubies.
The Identification of Blue Diffusion-Treated Sapphires
Blue diffusion-treated sapphires are becoming more prevalent than ever before.
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.
Jaipur, India: The Global Gem and Jewelry Power of the Pink City
Examines Jaipur’s role as a colored stone cutting and jewelry manufacturing center, with profiles of 17 companies and their factory, trading, and retail operations.
Reversible Color Modification of Blue Zircon by Long-Wave Ultraviolet Radiation
Determines whether blue zircon, inadvertently altered to brown by exposure to long-wave UV radiation, can be restored to its original color through the use of incandescent light.
The Chinese Red Feldspar Controversy: Chronology of Research Through July 2009
Red copper-containing plagioclase feldspar from Oregon has been available for over a century. In the early 2000s, new localities for copper-bearing feldspar were reported from the Democratic Republic of the Congo and from Tibet or an unspecified locality in China.
Gem-Quality Andalusite from Brazil
idely known as a rock-forming mineral, andalusite is not frequently encountered as a gem material.
Spectral Differentiation Between Copper and Iron Colorants in Gem Tourmalines
The authors used Vis-NIR spectral measurements combined with LA-ICP-MS data to investigate the usefulness of absorption spectra.
Characterization of “Green Amber” With Infrared and Nuclear Magnetic Resonance Spectroscopy
A peridot-like bright greenish yellow to green gem material called “green amber” has recently appeared in the gem market.
Identification of “Pistachio” Colored Pearls Treated by Ballerina Pearl Co.
A report on the color treatment process for these intensely greenish yellow to yellowish green cultured pearls and the techniques for identifying them.