Physical and Optical Properties of Gemstones
Learn about gemstone color, crystallography, hardness, chemical makeup and more.
Turquoise Color and the Color Turquoise
Turquoise Care Guide
Jade Toughness and Care
Gemstone Optics: The Basics
Gemstone Optical Properties
What is Gemstone Cleavage?
Descriptive Crystallography for Gemologists
Gemstone Color Measurements and Specifications
Gemstone Color Change Phenomena
What are Allochromatic and Idiochromatic Gems?
Phenomenal Gems: Cat’s Eyes, Star Stones, and More
Gemstone Physical Properties
What are Gemstone Enhancements?
Gemstone Thermal Properties
What is Gemstone Pleochroism?
Gemstone Magnetism: The Forgotten Property
What is a Trapiche Emerald?
What is Gemstone Luminescence?
Evaluating Gem Color: Hue, Tone, and Saturation
Understanding Color in Gemology
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