Rock & Mineral Encyclopedia

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

Graphic Granite

A pegmatitic granite in which quartz and feldspar intergrow to resemble ancient runic or Hebrew script.

A rare granitic rock containing concentric, onion-like spheres called orbicules, prized as a striking ornamental stone.

A Norwegian larvikite dimension stone prized for its shimmering blue iridescent feldspar crystals.

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

A distinctive tourmaline-rich granite from Cornwall, prized as an ornamental stone for its pink feldspar set with radiating black tourmaline.

An altered granite of pink feldspar, green epidote and quartz, mottled pink-and-green and popular as a tumbled and carving stone.

A Norwegian intrusive rock whose feldspar crystals flash silvery-blue, widely used as blue pearl granite countertops.

A pegmatite rock of feldspar intergrown with wedge-shaped quartz that resembles ancient runic or Hebrew writing.

A bright yellow, radioactive potassium uranyl vanadate that is a major ore of both uranium and vanadium.

A rare swirling lilac-to-violet silicate found only in Siberia, prized for its fibrous, chatoyant purple patterns.

A soft, green iron-potassium mica that forms in marine sediments and gives greensand its characteristic olive color.

A foliated metamorphic rock dominated by glittering dark biotite mica, formed from mudstones under medium-grade regional metamorphism.

A green, glauconite-rich marine sandstone that records slow deposition on continental shelves and is used as a soil amendment.

A soft lithium-bearing mica with a lilac to purple color and pearly, flaky sheen, an important ore of lithium.

A granite-like rock containing orthopyroxene, formed at high temperatures and pressures and often classed with the granulites.