Rock & Mineral Encyclopedia
Search and identify 1,000+ rocks, minerals, crystals, and gemstones — with properties, formation, colors, hardness, and how to tell them apart.
Aquamarine Matrix
Aquamarine crystals still attached to their natural host rock, prized as mineral specimens showing beryl in its original pocket setting.
mineralEmerald in Matrix
Natural emerald crystals still embedded in their host rock, prized as mineral specimens that show how the gem grew in place.
gemstoneSmoky Quartz
The smoky brown to gray variety of quartz, colored by natural irradiation, valued as both a gemstone and crystal specimen.
crystalRose Quartz
The soft pink, usually cloudy variety of quartz colored by trace titanium or microscopic inclusions, popular for carvings and beads.
crystalStrawberry Quartz
A pink-to-red quartz colored by iron oxide inclusions that create a speckled, strawberry-like appearance within clear crystal.
crystalMorion Quartz
The darkest, near-opaque black variety of smoky quartz, colored by natural radiation acting on trace aluminum.
crystalLithium Quartz
A quartz crystal containing pink to lilac lithium-bearing mineral inclusions that give a soft cloudy lavender or rose coloration.
crystalTibetan Quartz
Clear quartz mined in the Himalayan region, often double-terminated and containing dark hematite or carbon inclusions.
crystalTourmalinated Quartz
Clear or milky quartz threaded with black needles of tourmaline (schorl), combining quartz clarity with dramatic dark inclusions.
crystalStar Rose Quartz
Rose quartz that displays a six-rayed star (asterism) when cut as a cabochon, caused by microscopic rutile-like inclusions.
gemstoneMorganite Crystal
The natural crystal form of morganite, the manganese-colored pink-to-peach variety of beryl popular in romantic jewelry.
crystalEmerald Crystal
The natural crystalline form of emerald, the prized green chromium-and-vanadium variety of beryl and the May birthstone.
crystalCranberry Tourmaline
A deep cranberry-red to purplish-pink variety of lithium-rich elbaite tourmaline, prized as a rich, saturated rubellite gemstone.
gemstoneHonduran Opal
Precious opal from Honduras occurring in a dark volcanic matrix, where bright flecks of color flash against a natural black basalt background.
gemstoneSpiderweb Jasper
A jasper crossed by fine dark veins forming a spiderweb-like network, often a brecciated stone cemented by darker matrix.
mineralThulite
A pink, manganese-rich variety of zoisite used as an ornamental gemstone, often mottled with white quartz and grey matrix.
gemstoneBoulder Opal
Precious opal that forms in thin veins within brown ironstone boulders, cut with the host rock left as a natural dark backing.
gemstoneWacke
A poorly sorted, muddy sandstone with abundant clay matrix between its grains, typically dark and deposited by turbidity currents.
sedimentaryMatrix Opal
Opal in which precious play-of-color is intimately dispersed through the pores of its host rock rather than forming a solid seam.
gemstoneUnakite Jasper
An altered granite of pink feldspar, green epidote and quartz, mottled pink-and-green and popular as a tumbled and carving stone.
metamorphicSonoran Sunset Jasper
A vivid copper-bearing Mexican stone of red cuprite and green chrysocolla that evokes a desert sunset.
mineralUnakite
An altered granite mottled pink and green from feldspar and epidote, popular as a tough, colorful ornamental rock.
metamorphicSard
A brownish-red to deep brown variety of chalcedony, closely related to carnelian but darker, colored by iron oxides.
mineralPink Agate
A soft pink banded chalcedony, occurring naturally in delicate hues and also commonly produced by dyeing.
gemstone