Rock Identifier

Rock & Mineral Encyclopedia

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

Magnesite

Magnesite

A magnesium carbonate mineral, usually chalky white with grey veining, widely dyed to imitate turquoise and other stones.

mineral

Alabaster

A soft, fine-grained, translucent form of gypsum (or banded calcite) long prized as a carving and ornamental stone.

mineral

Carrara Marble

A famous white to blue-grey Italian marble from Carrara, prized for centuries by sculptors and architects for its purity and fine grain.

metamorphic
Coober Pedy Opal

Coober Pedy Opal

Australia's classic light-bodied precious opal from Coober Pedy, famed for milky white stones flashing pastel rainbow play-of-color.

gemstone

Pentelic Marble

The fine white marble of Mount Pentelikon used to build the Parthenon, famous for the golden patina it develops with age.

metamorphic
Clear Beryl

Clear Beryl

Transparent, colorless beryl (goshenite), the pure form of the species valued for its clarity, hardness, and well-formed crystals.

gemstone
Skutterudite

Skutterudite

A metallic cobalt-nickel arsenide, an important cobalt ore, named for the Skutterud mines of Norway.

mineral

Leuco Garnet

The rare colorless variety of grossular garnet, a near-flawless transparent gem free of the iron and chromium that color most garnets.

gemstone
Australian Opal

Australian Opal

Opal from Australia, the world's leading source of precious opal, ranging from white and crystal to prized black and boulder types.

gemstone
Apophyllite

Apophyllite

A glassy, often colorless silicate that forms pyramid-tipped cubes and is famed for its pearly basal cleavage and watery clarity.

crystal
Danburite

Danburite

A glassy calcium borosilicate forming wedge-tipped prismatic crystals, usually colorless to pale yellow or pink, sometimes faceted as a gem.

crystal
Parian Marble

Parian Marble

A pure, translucent white marble from the Greek island of Paros, the preferred stone of ancient sculptors for its waxy glow.

metamorphic
Chalk

Chalk

A soft, white, fine-grained limestone made almost entirely of microscopic marine plankton skeletons.

sedimentary
Platinum

Platinum

A dense, durable, silvery-white precious metal that resists corrosion, used in fine jewelry and catalytic converters.

mineral
Clear Quartz

Clear Quartz

The pure, colorless form of crystalline quartz, valued for its clarity, abundance, and piezoelectric properties used in electronics.

crystal
Cobaltite

Cobaltite

A silver-white cobalt arsenic sulfide that is a leading ore of cobalt, forming bright metallic cubic and pyritohedral crystals.

mineral
Chalcedony

Chalcedony

A waxy, translucent microcrystalline form of quartz that serves as the parent group for agate, jasper, carnelian, and onyx.

mineral
Cerussite

Cerussite

A dense lead carbonate mineral forming brilliant colorless to white crystals, an important ore of lead and a favorite of collectors.

mineral
Paragonite Schist

Paragonite Schist

A pale, silvery schist dominated by paragonite, the sodium-rich white mica, formed in aluminous metamorphic rocks.

metamorphic
Albite

Albite

The sodium end-member of the plagioclase feldspar series, a common white rock-forming mineral and parent of peristerite moonstone.

mineral

Frost Agate

A pale chalcedony agate with cloudy, frost-like white patterning suggesting frost on a window or icy crystalline textures.

gemstone

Milk Opal

An opaque to translucent milky-white common opal valued for its soft porcelain-like color rather than play-of-color.

gemstone
Blood Agate

Blood Agate

A deep red banded agate colored by iron oxides, valued as a vivid red lapidary and jewelry stone.

gemstone
Anglesite

Anglesite

A heavy lead sulfate secondary mineral, often colorless to white with adamantine luster, formed by the oxidation of galena.

mineral