Rock & Mineral Encyclopedia
Search and identify 1,000+ rocks, minerals, crystals, and gemstones — with properties, formation, colors, hardness, and how to tell them apart.

Bloodstone
A dark green chalcedony speckled with blood-red spots of iron oxide, traditionally known as heliotrope.
gemstone
Sapphire
The gem variety of corundum in every color except red, most prized in velvety blue and exceptionally hard and durable.
gemstone
Tiger Iron
A banded combination rock of golden tiger's eye, red jasper, and metallic hematite, formed in ancient iron deposits.
metamorphic
Imperial Garnet
A trade name for high-brilliance golden grossular-andradite (grandite) garnet, most associated with the Mali deposits of West Africa.
gemstone
Mali Garnet
A rare grossular-andradite blend ('grandite') from Mali, prized for its high brilliance and golden-green to yellow color.
gemstone
Pink Tourmaline
A pink to red gem variety of elbaite tourmaline, colored by manganese, ranging from soft pastel pink to vivid rubellite red.
gemstone
Hematite
The principal iron ore, a heavy iron oxide ranging from metallic silver-gray to earthy red, always leaving a tell-tale red-brown streak.
mineral
Khondalite
A high-grade metamorphic gneiss of garnet, sillimanite, quartz, and graphite, derived from ancient aluminous sediments.
metamorphic
Cinnabar
A bright red mercury sulfide, the chief ore of mercury and the historic source of the pigment vermilion.
mineral
Sunset Tourmaline
A warm-hued tourmaline blending orange, pink and red tones reminiscent of a sunset sky.
gemstone
Noreena Jasper
A rare Australian jasper from the Pilbara with bold red, yellow, and black abstract patterns, prized by collectors.
mineral
Kentucky Agate
The official state rock of Kentucky, a banded agate famous for striking deep-red and black fortification patterns.
gemstone
Jaspillite
A banded, metamorphosed iron formation in which bright red jasper alternates with silvery hematite or magnetite layers.
metamorphic
Sonoran Sunset Jasper
A vivid copper-bearing Mexican stone of red cuprite and green chrysocolla that evokes a desert sunset.
mineral
Outback Jasper
An earthy Australian-style jasper in red, ochre, and yellow tones evoking the colors of the Outback desert.
mineral
Carver Agate
A collectible Oregon plume and scenic agate with feathery red and gold inclusions suspended in translucent chalcedony.
gemstone
Rhodochrosite
Rhodochrosite is a rose-pink manganese carbonate prized for raspberry-red crystals and banded pink-and-white gem material.
gemstone
Pyrope Garnet
The magnesium-rich garnet famed for its intense blood-red 'fire,' historically the Bohemian garnet of Victorian jewelry.
gemstone
Flame Agate
A chalcedony agate with red, orange, and yellow plume or banding patterns that rise like dancing flames within the stone.
gemstone
Condor Agate
A vividly banded fortification agate from Argentina prized for its bold red, gold and white concentric patterns.
gemstone
Sard
A brownish-red to deep brown variety of chalcedony, closely related to carnelian but darker, colored by iron oxides.
mineral
Staurolite-mica Schist
A mica schist studded with red-brown staurolite porphyroblasts, including the famous cross-shaped twins called fairy stones.
metamorphic
Pyralspite Garnet
Pyralspite is the aluminum garnet series uniting pyrope, almandine, and spessartine, covering most red, orange, and purple gem garnets.
mineral
Mookaite Jasper
An Australian silicified radiolarite jasper in warm mustard, red, burgundy, and cream earth tones, found only in Western Australia.
sedimentary