Rock & Mineral Encyclopedia
Search and identify 1,000+ rocks, minerals, crystals, and gemstones — with properties, formation, colors, hardness, and how to tell them apart.
Labradorite
A plagioclase feldspar famous for labradorescence, a dramatic flash of iridescent blue, green, and gold across a dark gray stone.
mineral
Blue Jasper
An opaque blue variety of chalcedony jasper, less common than red or green forms, colored by mineral inclusions.
mineralExotica Jasper
Also called Sci-Fi Jasper, a Mexican jasper-rhyolite with swirling abstract patterns in cream, tan, gray, pink, and green.
gemstone
Chrysocolla
A vivid blue-green hydrated copper silicate, soft on its own but prized as a gem when hardened by intergrown quartz or chalcedony.
mineralPeruvian Blue Opal
A translucent common opal from the Andes prized for its serene blue to blue-green color, usually cut into cabochons and beads.
gemstone
Turquoise
A prized blue to blue-green copper-aluminium phosphate, often veined with dark matrix, treasured for jewelry across many cultures.
mineral
Nephrite
One of the two jade minerals, an amphibole prized for its extreme toughness and soft, waxy green hues used in carving for millennia.
gemstoneMorrisonite Jasper
A rare, prized Oregon picture jasper known for blue-green orbs and scenic patterns, often called the king of jaspers.
mineral
Andalusite
A pleochroic aluminum silicate that flashes green and reddish-brown from different angles, with a cross-marked variety called chiastolite.
mineral
Jadeite
The rarer and more valuable of the two jade minerals, prized for its translucent emerald-green 'imperial' color and extreme toughness.
gemstone
Reedmergnerite
A rare boron-bearing feldspar, the boron analogue of albite, first found in oil-shale nodules of the Green River Formation.
mineral
Gahnite
A hard zinc-rich member of the spinel group, usually dark blue-green to black, forming octahedral crystals in metamorphic and pegmatitic rocks.
mineralMadagascar Opal
Opal from Madagascar spanning colorful common opal and some precious opal, including pink, green and boulder-type material.
gemstoneReptile Jasper
A green-and-black mottled jasper whose scale-like patterning resembles reptile skin, often linked to Kambaba and crocodile jaspers.
mineral
Garnet
A group of silicate gemstones best known for deep red but spanning nearly every color, including green tsavorite and orange spessartine.
gemstone
Eclogite
A dense, high-pressure metamorphic rock famous for its red garnets set in bright green pyroxene, formed deep within subduction zones.
metamorphic
Alexandrite
A rare color-change chrysoberyl that appears green in daylight and red under incandescent light, sometimes called emerald by day, ruby by night.
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
Quartz Schist
A foliated metamorphic rock dominated by quartz with enough mica to give it a schistose, splitting fabric.
metamorphic
Schist
A medium-grade metamorphic rock rich in aligned platy minerals that gives it a shiny, easily splitting, foliated texture.
metamorphicMarl
A soft, earthy sedimentary rock made of a mixture of calcium carbonate and clay, intermediate between limestone and mudstone.
sedimentary
Diabase
A tough, dark, medium-grained igneous rock with the composition of basalt, common in dikes and sills.
igneousQuartz Arenite
A clean, mature sandstone made almost entirely of quartz grains, representing extreme weathering, sorting, and recycling of sediment.
sedimentary
Metabasalt
Basalt that has been metamorphosed, developing new minerals like chlorite, actinolite, and epidote that give it a greenish color.
metamorphic