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
A manganese aluminum garnet glowing in vivid orange to reddish-orange tones, with the finest called mandarin garnet.
gemstone
Melanite Garnet
The titanium-rich black variety of andradite garnet, with a brilliant resinous luster prized for mourning and statement jewelry.
gemstone
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
A rare green andradite garnet famed for fire exceeding diamond and distinctive horsetail inclusions in Russian stones.
gemstoneBekily 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
Ugrandite Garnet
Ugrandite is the calcium garnet series uniting uvarovite, grossular, and andradite, including tsavorite and the fiery demantoid.
mineralGooseberry Garnet
Gooseberry Garnet is a soft green grossular garnet named for its resemblance to the pale, translucent green of ripe gooseberries.
gemstone
Bohemian Garnet
Small, intensely red chrome-pyrope garnets from the Czech Bohemian region, famous for densely set antique Victorian jewelry.
gemstone
Color Change Garnet
A rare garnet that dramatically shifts color from greenish in daylight to reddish under lamplight, rivaling alexandrite.
gemstone
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
A synthetic garnet-structured oxide (YAG) used as a diamond simulant and laser crystal, with no natural counterpart.
gemstoneMasasi 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
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
Ant Hill Garnet
Small, bright chrome-pyrope garnets famously brought to the surface by harvester ants on the Navajo lands of Arizona.
gemstone
Honduran Opal
Precious opal from Honduras occurring in a dark volcanic matrix, where bright flecks of color flash against a natural black basalt background.
gemstone
Boulder Opal
Precious opal that forms in thin veins within brown ironstone boulders, cut with the host rock left as a natural dark backing.
gemstone
Andamooka Opal
Precious opal from the Andamooka field of South Australia, famous for solid crystal opal and its distinctive treatable matrix opal.
gemstone
Wacke
A poorly sorted, muddy sandstone with abundant clay matrix between its grains, typically dark and deposited by turbidity currents.
sedimentary
Majorite
An ultra-high-pressure garnet with silicon in the octahedral site, formed in the deep mantle transition zone and in shocked meteorites.
mineralHutcheonite
A titanium-aluminum garnet discovered in calcium-aluminum inclusions of the Allende meteorite, recording the earliest history of the solar system.
mineral
Goldmanite
A green, vanadium-dominant garnet that forms in vanadium-rich metamorphic and sedimentary rocks, notably in uranium-vanadium districts.
mineral
Calderite
A manganese-iron garnet that forms in metamorphosed manganese deposits, intermediate in composition between spessartine and andradite.
mineral
Kimzeyite
A rare zirconium-bearing garnet that crystallizes in carbonatites and alkaline rocks, first described from Magnet Cove, Arkansas.
mineral