Rock & Mineral Encyclopedia
Search and identify 1,000+ rocks, minerals, crystals, and gemstones — with properties, formation, colors, hardness, and how to tell them apart.
Granodiorite
A common coarse-grained intrusive rock like granite but richer in plagioclase than potassium feldspar.
igneous
Rhodonite
A rose-pink manganese silicate marbled with black veins, prized as a tough ornamental and occasionally faceted gemstone.
mineral
Dacite
A fine-grained volcanic rock intermediate between andesite and rhyolite, common at explosive stratovolcanoes.
igneousFrog Skin Jasper
A mottled green jasper whose blotchy spotting resembles frog skin, valued by lapidaries for its earthy, camouflage-like patterns.
gemstone
Gabbro
A coarse-grained, dark mafic intrusive rock that is the plutonic equivalent of basalt, rich in plagioclase and pyroxene.
igneous
Cranberry Tourmaline
A deep cranberry-red to purplish-pink variety of lithium-rich elbaite tourmaline, prized as a rich, saturated rubellite gemstone.
gemstone
Sanidine
A high-temperature potassium feldspar that forms glassy crystals in fast-cooled volcanic rocks, sometimes cut as a moonstone gem.
mineral
Rose Quartz
The soft pink, usually cloudy variety of quartz colored by trace titanium or microscopic inclusions, popular for carvings and beads.
crystal
Raspberry Beryl
A trade name for raspberry-pink beryl-family gems, most often the cesium-rich mineral pezzottaite from Madagascar.
gemstone
Rosolite Garnet
A rose-pink variety of grossular garnet from Mexico, also known as landerite or xalostocite, prized for its soft pink color.
gemstone
Morganite Crystal
The natural crystal form of morganite, the manganese-colored pink-to-peach variety of beryl popular in romantic jewelry.
crystal
Raspberry Tourmaline
A vivid raspberry-pink to pinkish-red elbaite tourmaline, a bright, cheerful member of the rubellite family colored by manganese.
gemstoneSunset Tourmaline
A warm-hued tourmaline blending orange, pink and red tones reminiscent of a sunset sky.
gemstoneCobalt Blue Obsidian
A deep cobalt-blue glass sold as obsidian; intense blue body color is manufactured, as natural obsidian does not form bright blue glass.
igneous
Peach Tourmaline
A gentle peachy-pink tourmaline blending soft pink and orange tones, a delicate pastel variety of elbaite.
gemstone
Rubellite
The red to raspberry-pink variety of tourmaline, prized for its vivid ruby-like color that holds under both daylight and artificial light.
gemstoneStrawberry Obsidian
A pink-red glass sold as obsidian, sometimes with metallic flecks; the strawberry color is manufactured rather than a natural volcanic glass tone.
igneous
Raspberry Garnet
A vivid pinkish-red rhodolite garnet named for its raspberry color, a bright pyrope-almandine blend popular in jewelry.
gemstoneWatermelon Obsidian
A pink-and-green bicolor glass sold as obsidian; the watermelon coloring is manufactured and does not occur in natural volcanic glass.
igneous
Strawberry Quartz
A pink-to-red quartz colored by iron oxide inclusions that create a speckled, strawberry-like appearance within clear crystal.
crystal
Lepidolite
A soft lithium-bearing mica with a lilac to purple color and pearly, flaky sheen, an important ore of lithium.
mineral
Purple Tourmaline
An uncommon purple to violet tourmaline colored by manganese, the deeper reddish-purple stones sometimes called siberite.
gemstoneUmbalite Garnet
A delicate pink to lavender garnet from Tanzania's Umba Valley, a pyrope-spessartine blend often marketed as a soft, light-toned rhodolite.
gemstone
Watermelon Tourmaline
A striking color-zoned tourmaline with a pink center and green rind, resembling a slice of watermelon when cut across the crystal.
gemstone