Rock Identifier

Rock & Mineral Encyclopedia

Search and identify 1,000+ rocks, minerals, crystals, and gemstones — with properties, formation, colors, hardness, and how to tell them apart.

Demantoid Garnet

Demantoid Garnet

A rare green andradite garnet famed for fire exceeding diamond and distinctive horsetail inclusions in Russian stones.

gemstone

Masasi Blue Garnet

Masasi Blue Garnet is a rare vanadium-bearing color-change garnet from Tanzania that appears blue-green by day and purplish-red indoors.

gemstone
Spessartite Garnet

Spessartite Garnet

A manganese aluminum garnet glowing in vivid orange to reddish-orange tones, with the finest called mandarin garnet.

gemstone
Chrome Pyrope

Chrome Pyrope

A chromium-rich pyrope garnet whose intense blood-red color comes from chromium, often mined from ant hills and kimberlite weathering.

gemstone
Goldmanite

Goldmanite

A green, vanadium-dominant garnet that forms in vanadium-rich metamorphic and sedimentary rocks, notably in uranium-vanadium districts.

mineral
Kimzeyite

Kimzeyite

A rare zirconium-bearing garnet that crystallizes in carbonatites and alkaline rocks, first described from Magnet Cove, Arkansas.

mineral

Morimotoite

A black titanium garnet related to andradite and schorlomite, containing tetravalent titanium and ferrous iron, found in skarns and alkaline rocks.

mineral

Hydroandradite

A hydrous, iron-rich garnet of the hydrogarnet group in which hydroxyl groups substitute for silica within the andradite structure.

mineral

Arizona Ruby

Arizona Ruby is a chromium-rich pyrope garnet from Arizona, often gathered from anthills, valued for its intense ruby-like red.

gemstone

Plazolite

A hydrogrossular garnet first described from Crestmore, California, now regarded as equivalent to hibschite in the hydrogarnet series.

mineral

Kerimasite

A zirconium-rich garnet related to kimzeyite, formed in carbonatites and skarns, named after the Kerimasi volcano in Tanzania.

mineral

Hutcheonite

A titanium-aluminum garnet discovered in calcium-aluminum inclusions of the Allende meteorite, recording the earliest history of the solar system.

mineral
Calderite

Calderite

A manganese-iron garnet that forms in metamorphosed manganese deposits, intermediate in composition between spessartine and andradite.

mineral
Hibschite

Hibschite

A hydrous aluminum garnet (hydrogrossular) intermediate between grossular and katoite, common in altered calcium-rich and serpentinized rocks.

mineral

Chrome Spessartine

Chrome Spessartine is a rare chromium-bearing manganese garnet whose trace chromium intensifies its already vivid orange color.

gemstone
Tactite

Tactite

A contact-metasomatic calc-silicate rock, essentially a skarn, formed where intrusions react with carbonate rocks and often host ore.

metamorphic
Skarn

Skarn

A calc-silicate rock formed by chemical exchange between magma and carbonate rock, often rich in garnet and economically important ore minerals.

metamorphic
Majorite

Majorite

An ultra-high-pressure garnet with silicon in the octahedral site, formed in the deep mantle transition zone and in shocked meteorites.

mineral
Schorlomite

Schorlomite

A lustrous black titanium-rich garnet of the andradite series, found in alkaline igneous rocks like nepheline syenite and ijolite.

mineral
Katoite

Katoite

The water-rich end-member of the hydrogrossular series, a soft hydrogarnet found in altered rocks and known from cement chemistry.

mineral

Knorringite

A chromium-rich magnesium garnet of the pyrope series that crystallizes in the deep mantle and is a valuable diamond indicator mineral.

mineral
Eclogite

Eclogite

A dense, high-pressure metamorphic rock famous for its red garnets set in bright green pyroxene, formed deep within subduction zones.

metamorphic

Eltyubyuite

A rare chlorine-bearing iron garnet-supergroup mineral, the ferric analogue of wadalite, formed in high-temperature combustion-metamorphic rocks.

mineral
Cinnamon Stone

Cinnamon Stone

The warm cinnamon-to-honey-brown variety of grossular garnet, also known as hessonite, with a characteristic swirly internal texture.

gemstone