Rock & Mineral Encyclopedia
Search and identify 1,000+ rocks, minerals, crystals, and gemstones — with properties, formation, colors, hardness, and how to tell them apart.
Schist
A medium-grade metamorphic rock rich in aligned platy minerals that gives it a shiny, easily splitting, foliated texture.
metamorphicMint Garnet
A delicate pastel-green grossular garnet, lighter than tsavorite, most famously from the Merelani Hills of Tanzania.
gemstone
Diabase
A tough, dark, medium-grained igneous rock with the composition of basalt, common in dikes and sills.
igneous
Tree Agate
A white chalcedony filled with green or black dendritic, tree-like mineral inclusions that resemble ferns or moss frozen in stone.
gemstone
Emerald
The green chromium- and vanadium-colored variety of beryl, one of the four classic precious gemstones renowned for its rich green color.
gemstoneJelly Garnet
Jelly Garnet is a translucent grossular garnet whose soft, glassy, gummy-looking body gives it a jelly-like appearance.
gemstone
Hornblende Schist
A dark, foliated schist rich in needle-like hornblende crystals, formed by metamorphism of mafic igneous rocks.
metamorphic
Apophyllite
A glassy, often colorless silicate that forms pyramid-tipped cubes and is famed for its pearly basal cleavage and watery clarity.
crystal
Emerald Crystal
The natural crystalline form of emerald, the prized green chromium-and-vanadium variety of beryl and the May birthstone.
crystal
Olive Tourmaline
An earthy olive to yellowish-green tourmaline, a muted green-brown gem variety colored by iron with subtle warm undertones.
gemstone
Willemite
A zinc silicate famous for its brilliant green fluorescence under shortwave UV light, especially from Franklin, New Jersey.
mineral
Pyromorphite
A lead phosphate secondary mineral known for barrel-shaped green to yellow crystals formed in oxidized lead deposits.
mineral
Chrome Chalcedony
A vivid green chalcedony colored by chromium, often called mtorolite, resembling chrysoprase but owing its color to chromium rather than nickel.
gemstoneGooseberry Garnet
Gooseberry Garnet is a soft green grossular garnet named for its resemblance to the pale, translucent green of ripe gooseberries.
gemstone
Kyanite
A bladed aluminosilicate famous for having two very different hardnesses depending on the direction you scratch it.
mineral
Mint Tourmaline
A soft, pastel minty-green tourmaline prized for its fresh, light color, a delicate variety of green elbaite.
gemstone
Metabasalt
Basalt that has been metamorphosed, developing new minerals like chlorite, actinolite, and epidote that give it a greenish color.
metamorphic
Jade
A tough, prized ornamental gem that is actually two distinct minerals, jadeite and nephrite, revered for millennia in many cultures.
gemstone
Moss Agate
A translucent chalcedony filled with green or brown dendritic mineral inclusions that resemble moss, foliage, or landscapes.
gemstone
Transvaal Jade
A massive green-to-pink hydrogrossular garnet from South Africa used as a jade simulant, not a true jade.
gemstone
Chrome Diopside
A vivid green chromium-bearing diopside, an affordable emerald-like gem mined largely in Siberia.
gemstoneTurquoise Obsidian
A vivid turquoise-blue glass sold as obsidian; this bright color is virtually always manufactured rather than natural volcanic glass.
igneous
Garnierite
A vivid green hydrous nickel-magnesium silicate that is a major ore of nickel, mined from weathered ultramafic rocks.
mineral
Prehnite
A translucent yellow-green silicate famous for its botryoidal 'grape' clusters, often hosting needle-like sprays of black epidote.
mineral