The Gemstone Encyclopedia
Discover the world's most beautiful gemstones. Properties, origins, comparisons, and expert guides — all in one place.
Today's Gemstone
Smoky Quartz
Semi-Precious Gems
Smoky Quartz is Scotland's national gemstone, a brown to black irradiated quartz used in Celtic jewelry since antiquity, found in Brazil and the Swiss Alps.
Featured Gemstones
View all →Alexandrite
Hardness: 8.5
Almandine
Hardness: 7.0
Amazonite
Hardness: 6.0
Amber
Hardness: 2.0
Amethyst
Hardness: 7.0
Apatite
Hardness: 5.0
Aquamarine
Hardness: 7.5
Aventurine
Hardness: 7.0
Benitoite
Hardness: 6.0
Black Opal
Hardness: 6.0
Bloodstone (Heliotrope)
Hardness: 6.5
Carnelian
Hardness: 6.5
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