The Gemstone Encyclopedia
Discover the world's most beautiful gemstones. Properties, origins, comparisons, and expert guides — all in one place.
Today's Gemstone
Demantoid
Semi-Precious Gems
Demantoid is the green andradite garnet with dispersion exceeding diamond, producing spectacular fire. Russian 'horsetail' inclusion stones are the most prized; also from Namibia. Hardness 6.5–7.
Featured Gemstones
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Hardness: 8.5
Onyx
Hardness: 6.5
Sapphire
Hardness: 9.0
Moldavite
Hardness: 5.5
Aquamarine
Hardness: 7.5
Kunzite
Hardness: 6.0
Zircon
Hardness: 7.5
Benitoite
Hardness: 6.0
Spessartine
Hardness: 7.0
Bloodstone (Heliotrope)
Hardness: 6.5
Charoite
Hardness: 5.0
Carnelian
Hardness: 6.5
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