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.

Montana Garnet

Montana Garnet is red almandine recovered from Montana placer gravels, often alongside the state's famous sapphires.

gemstone
Spessartite Garnet

Spessartite Garnet

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

gemstone
Melanite Garnet

Melanite Garnet

The titanium-rich black variety of andradite garnet, with a brilliant resinous luster prized for mourning and statement jewelry.

gemstone
Uvarovite Garnet

Uvarovite Garnet

The rare calcium-chromium garnet, famous for its sparkling emerald-green druzy crusts of tiny crystals, the only consistently green garnet.

mineral
Demantoid Garnet

Demantoid Garnet

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

gemstone

Bekily Garnet

A rare color-change garnet from Bekily, Madagascar, shifting from bluish-green in daylight to purplish-red under warm light, including the famed blue garnets.

gemstone
Color Change Garnet

Color Change Garnet

A rare garnet that dramatically shifts color from greenish in daylight to reddish under lamplight, rivaling alexandrite.

gemstone
Merelani Mint Garnet

Merelani Mint Garnet

A delicate vanadium-colored mint-green grossular garnet from the Merelani Hills of Tanzania, the source of tanzanite.

gemstone
Yttrium Aluminum Garnet

Yttrium Aluminum Garnet

A synthetic garnet-structured oxide (YAG) used as a diamond simulant and laser crystal, with no natural counterpart.

gemstone
Idaho Star Garnet

Idaho Star Garnet

Idaho's official state gem: a dark almandine garnet showing a four- or rare six-rayed star from oriented rutile inclusions.

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
Ant Hill Garnet

Ant Hill Garnet

Small, bright chrome-pyrope garnets famously brought to the surface by harvester ants on the Navajo lands of Arizona.

gemstone
Lithic Sandstone

Lithic Sandstone

A sandstone in which the dominant grains are fragments of pre-existing rocks rather than single minerals, signaling rapid erosion nearby.

sedimentary
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
Goldmanite

Goldmanite

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

mineral

Hutcheonite

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

mineral
Kimzeyite

Kimzeyite

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

mineral
Calderite

Calderite

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

mineral

Kerimasite

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

mineral

Matte Obsidian

Obsidian with a dull, non-reflective surface from natural weathering or deliberate sandblasting/etching, rather than a distinct type of volcanic glass.

igneous

Morimotoite

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

mineral

Eltyubyuite

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

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
Cape Ruby

Cape Ruby

Cape Ruby is a deep red pyrope garnet from South African diamond deposits, prized as an affordable, fiery alternative to ruby.

gemstone