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What are Crystal Systems and Mineral Habits?

Step 1: Introduction to Gemology Lesson 7 Back to syllabus When sulfur forms into crystals, it forms in the orthorhombic system, just like alexandrite…

An Introduction to Gem Identification

Step 1: Introduction to Gemology Lesson 8 Back to syllabus Summary People often ask me about gem identification. More specifically, they ask me…

Recommended Gemology Tools and Instruments

Gemstone identification requires a good reference library and some basic gemology tools. Before you go shopping, learn more about what you’ll…

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…

Alexandrite Value, Price, and Jewelry Information

“Emerald by day, ruby by night,” alexandrite is well known for displaying one of the most remarkable color changes in the gem world — green…

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What are Crystal Systems and Mineral Habits?

An Introduction to Gem Identification

Recommended Gemology Tools and Instruments

Gemstone Toxicity Table

Alexandrite Value, Price, and Jewelry Information

An Introduction to Gemstone Inclusions

Identifying Inclusions of Specific Gems

What Does the GIA Colored Gem Grading Code Mean?

Gem Price Guide