Gemstone Guide
Clear, certificate-aware information for comparing natural stones.
Quartz
Amethyst
Mohs 7 · Purple
Beryl
Aquamarine
Mohs 7.5-8 · Blue to blue-green
Quartz
Citrine
Mohs 7 · Yellow to orange
Carbon
Diamond
Mohs 10 · Colorless and fancy colors
Beryl
Emerald
Mohs 7.5-8 · Green
Garnet group
Garnet
Mohs 6.5-7.5 · Red, green, orange and more
Jadeite / Nephrite
Jade
Mohs 6-7 · Green, white, lavender and more
Rock aggregate
Lapis Lazuli
Mohs 5-5.5 · Deep blue
Feldspar
Moonstone
Mohs 6-6.5 · Colorless, peach, gray
Beryl
Morganite
Mohs 7.5-8 · Pink to peach
Hydrated silica
Opal
Mohs 5.5-6.5 · All colors
Organic
Pearl
Mohs 2.5-4.5 · White, cream, black and more
Olivine
Peridot
Mohs 6.5-7 · Yellow-green to green
Quartz
Rose Quartz
Mohs 7 · Pale to medium pink
Corundum
Ruby
Mohs 9 · Red
Corundum
Sapphire
Mohs 9 · Blue and fancy colors
Spinel
Spinel
Mohs 8 · Red, pink, blue and more
Zoisite
Tanzanite
Mohs 6-7 · Blue to violet
Topaz
Topaz
Mohs 8 · Blue, yellow, pink and more
Tourmaline group
Tourmaline
Mohs 7-7.5 · Nearly every color
Turquoise
Turquoise
Mohs 5-6 · Blue to green
Zircon
Zircon
Mohs 6-7.5 · Colorless, blue, brown and more
Chalcedony
Agate
Mohs 6.5-7 · Banded, many colors
Quartz
Quartz
Mohs 7 · Colorless and many colors
Chalcedony
Onyx
Mohs 6.5-7 · Black, white-banded