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Gemstone Toxicity Table

Gem faceters and jewelry enthusiasts alike should learn about gemstone toxicity. This table has toxicity ratings for 280+ gems, based on their…

What is Gemstone Birefringence?

A gemstone’s birefringence is a measure of its double refraction. Learn how to use it to identify gems and see the effects birefringent gems can…

Conch Pearl Buying Guide

Considering a conch pearl buying trip to the Caribbean? Quality factors for these gems differ from colored gemstones. Before you make a purchase,…