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.

Cat's Eye Moonstone

A moonstone variety displaying a moving band of light (chatoyancy) across its surface in addition to the classic moonstone glow.

gemstone

Grey Moonstone

A smoky gray feldspar moonstone, often called new moon stone, showing a silvery-blue adularescent sheen over a translucent gray body.

gemstone
Latite

Latite

The fine-grained volcanic equivalent of monzonite, an intermediate lava with nearly equal feldspars and little free quartz.

igneous
Arkose

Arkose

A coarse, feldspar-rich sandstone, often pink, that records rapid erosion of granitic source rock under arid conditions.

sedimentary
Tonalite

Tonalite

A quartz-rich plutonic rock dominated by plagioclase feldspar with little alkali feldspar, closely related to granodiorite and quartz diorite.

igneous

Kiwi Jasper

A speckled green-and-black stone resembling kiwi fruit, technically a quartz-amazonite aggregate rather than true jasper.

mineral
Unakite

Unakite

An altered granite mottled pink and green from feldspar and epidote, popular as a tough, colorful ornamental rock.

metamorphic
Monzonite

Monzonite

An intermediate plutonic rock with nearly equal alkali and plagioclase feldspar and very little quartz, sitting between diorite and syenite.

igneous
Lead Feldspar

Lead Feldspar

A very rare lead-dominant feldspar composition, the lead analogue of anorthite, known largely from synthetic studies and lead-rich environments.

mineral
Black Moonstone

Black Moonstone

A dark gray-to-black feldspar variety of moonstone that shows blue and white adularescent flash against a smoky body.

gemstone

Sesame Jasper

A finely speckled pale jasper trade stone named for its sesame-seed-like flecks, closely related to Kiwi Jasper.

mineral
Snow Quartz

Snow Quartz

An opaque, snow-white variety of quartz whose milky color comes from countless tiny gas and fluid inclusions.

crystal
Rose Quartz

Rose Quartz

The soft pink, usually cloudy variety of quartz colored by trace titanium or microscopic inclusions, popular for carvings and beads.

crystal
Dalmatian Stone

Dalmatian Stone

A cream-colored feldspar-and-quartz rock peppered with dark spots, named for its resemblance to a Dalmatian dog.

igneous
Milky Quartz

Milky Quartz

The most common variety of quartz, milky white from microscopic fluid and gas inclusions, forming massive veins worldwide.

crystal
Smoky Quartz

Smoky Quartz

The smoky brown to gray variety of quartz, colored by natural irradiation, valued as both a gemstone and crystal specimen.

crystal
Lemon Quartz

Lemon Quartz

A vivid greenish-yellow quartz, usually heat-treated or irradiated, prized for its clean clarity and bright lemon color.

crystal
Golden Feldspar

Golden Feldspar

A trade name for golden-yellow gem feldspars, including golden orthoclase, golden sunstone, and golden labradorite.

gemstone
Barium Feldspar

Barium Feldspar

The barium end-member of the feldspar group, represented by celsian, occurring in barium-rich metamorphic and manganese deposits.

mineral
Khondalite

Khondalite

A high-grade metamorphic gneiss of garnet, sillimanite, quartz, and graphite, derived from ancient aluminous sediments.

metamorphic
Quartzite

Quartzite

An extremely hard metamorphic rock formed from sandstone, made of fused quartz grains that break across rather than between the grains.

metamorphic
Spirit Quartz

Spirit Quartz

A South African quartz whose central crystal is coated in tiny druzy points, also called cactus or fairy quartz.

crystal
Morion Quartz

Morion Quartz

The darkest, near-opaque black variety of smoky quartz, colored by natural radiation acting on trace aluminum.

crystal
Quartz Schist

Quartz Schist

A foliated metamorphic rock dominated by quartz with enough mica to give it a schistose, splitting fabric.

metamorphic