Reference Charts & Materials
Commonly used charts for gemology and jewelry and lapidary.
Emerald Origins: History and Identification
Diamond Lookalikes Listed by Specific Gravity
Standard Gem Sizes Chart
Gemology Cheat Sheets
How to Estimate Gem Weight in a Jewelry Setting
Table of Gems Ordered by Crystal System
Specific Gravity Values of Selected Gems
Table of Refractive Indices and Double Refraction of Selected Gems
Properties of Diamond Simulants
Gemstone Toxicity Table
The Mohs Hardness Scale and Chart for Select Gems
List of False or Misleading Gemstone Names
Gem Structure Chart
Weights and Measures Conversion Chart
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