Potentate’s Montana Sapphire Mine: An Interview with Warren Boyd
An update on the activity at Potentate’s Montana deposits.
U-Pb Ages of Zircon Inclusions in Sapphires from Ratnapura and Balangoda (Sri Lanka) and Implications for Geographic Origin
Establishes a metamorphic origin for sapphire samples from these deposits, supported by their trace-element composition and inclusion characterization, including the age dating of zircon inclusions.
Jeff Hapeman: Stories from a Gem Cutter
Jeff Hapeman of Earth’s Treasury (Westtown, Pennsylvania) loves a gemstone with a good story.
Trapiche Emerald from Colombia
The examination of a nearly complete trapiche emerald crystal–which are difficult to obtain–is consistent with the findings of previous studies.
CVD Layer Grown on Natural Diamond
A composite of synthetically grown and natural diamond was recently identified by the Carlsbad laboratory.
Jeffrey Bilgore Gems and Jewelry Designs
Eye-catching stones at Jeffrey Bilgore’s AGTA booth.
2019 Jewelry Industry Summit
The third Jewelry Industry Summit, held in Tucson February 2–3, revealed the successful implementation of several initiatives mapped out since the conference’s inception in 2016.
Recycled Gemstones from Perpetuum Jewels
A wholesaler supplying the bridal market with recycled gemstones and antique cuts shares his thoughts on the market and on responsible practices.
Provenance Discrimination of Freshwater Pearls by LA-ICP-MS and Linear Discriminant Analysis (LDA)
Investigates trace-element chemistry of freshwater natural pearls from North America and China with LA-ICP-MS and uses LDA to identify their origins.
Low-Fe, High-V Color-Change Burmese Sapphire
The Carlsbad lab identifies a color-change Burmese sapphire with a unique chemistry profile.
Pleochroism and Color Change in Faceted Alexandrite: Influence of Cut and Sample Orientation
Shows how alexandrite’s color and color change are affected by cut and the orientation of table facets.

Gray Spinel: A New Trend in Colored Stones
In recent years, the colored stone world has seen a growing appetite for unusual colors.
