The Gemstone Encyclopedia
Discover the world's most beautiful gemstones. Properties, origins, comparisons, and expert guides — all in one place.
442
Gemstones
15
Origins
43
Glossary Terms
Today's Gemstone
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Sapphire
Precious Gems
Sapphire is a blue corundum gem—one of the four precious stones—prized for cornflower hues from Kashmir, Myanmar, and Sri Lanka, September's birthstone.
Featured Gemstones
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Semi-Precious Gems
Alexandrite
Hardness: 8.5
Semi-Precious Gems
Almandine
Hardness: 7.0
Semi-Precious Gems
Amazonite
Hardness: 6.0
Organic Gems
Amber
Hardness: 2.0
Semi-Precious Gems
Amethyst
Hardness: 7.0
Semi-Precious Gems
Apatite
Hardness: 5.0
Semi-Precious Gems
Aquamarine
Hardness: 7.5
Semi-Precious Gems
Aventurine
Hardness: 7.0
Semi-Precious Gems
Benitoite
Hardness: 6.0
Semi-Precious Gems
Black Opal
Hardness: 6.0
Semi-Precious Gems
Bloodstone (Heliotrope)
Hardness: 6.5
Semi-Precious Gems
Carnelian
Hardness: 6.5
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