Classifying Emerald Clarity Enhancement at the GIA Gem Trade Laboratory
One of the greatest concerns with emerald filling is the degree of clarity enhancement such treatment represents
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.
Gray-To-Blue-To-Violet Hydrogen-Rich Diamonds from the Argyle Mine, Australia
The Argyle diamond mine is the only known source of type IaB hydrogen- and nitrogen-rich diamonds colored gray to blue to violet.
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.
Cutting Diffraction Gratings to Improve Dispersion (“Fire”) in Diamonds
A new microlithography process developed to create high-resolution diffraction grating patterns on portions of certain facets can improve the dispersion of light and thus the amount of “fire” in a diamond.
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.
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.
Gemstone Enhancement and its Detection in the 1980s
The impact that enhancements had on the gem market in the 1980s may be unparalleled in the history of the industry.
Chart of Commercially Available Gem Treatments
This chart combines a comprehensive listing of the commercially available treatments for the most commonly used gem materials with an indication of the current status of their detectability.