How COVID Has Impacted the Supply of Tourmaline and Zircon
March 3, 2022 Dealers showcased inventory that had been building over the last few years at the American Gem Trade Association (AGTA) and the Gems…
Gemstone Optical Properties
Learn how gemstone optical properties, like refractive index and pleochroism, help gemologists identify gems and lapidaries choose cuts.
Distinguishing Diamonds: Educating Your Eyes
Distinguishing diamonds from their lookalikes requires educated eyes. Learn what visual features to look for and the properties of many popular…
Refractometer Guide, Part 3: Determining Optic Character and Recognizing Optic Effects
Learn how to determine a gem’s optic character with a refractometer and identify optical effects you may encounter during gem identification…
Dealers at Tucson Gem Show Confirm Increasing Demand for Montana Sapphires
February 16, 2022 TUCSON — After a cancellation in 2021, the Tucson Gem Show returned to Arizona from February 10-13, 2022. The show, presented…
Spinel Buying Guide
Master spinel buying with our comprehensive guide covering the 4 Cs, color grading, pricing, origins, and how to identify quality natural vs synthetic…
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