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
💎
Grandidierite
Semi-Precious Gems
Grandidierite is an exceptionally rare blue-green trichroic borosilicate from Madagascar, first described in 1902.
Featured Gemstones
View all →
Semi-Precious Gems
Fluorite
Hardness: 4.0
Semi-Precious Gems
Pyrope
Hardness: 7.0
Semi-Precious Gems
Rhodolite
Hardness: 7.0
Semi-Precious Gems
Rose Quartz
Hardness: 7.0
Precious Gems
Ruby
Hardness: 9.0
Precious Gems
Sapphire
Hardness: 9.0
Semi-Precious Gems
Smoky Quartz
Hardness: 7.0
Semi-Precious Gems
Spessartine
Hardness: 7.0
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
Browse by Category
Browse by Color
Learn About Gemstones
From beginner basics to advanced gemology — explore our expert-written guides and interactive tools.