Rock & Mineral Encyclopedia

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

Pyrrhotite

A bronze-colored iron sulfide notable for being the most magnetic of the common sulfide minerals and an important nickel host.

A schist derived from clay-rich sediments, rich in mica and often bearing index minerals like garnet, staurolite, or kyanite.

A water-bearing massive grossular garnet, usually green or pink, widely used as a tough jade-like carving stone.

An earthy aluminum-rich residual rock and the world's principal ore of aluminum, often showing distinctive pea-like pisolites.

A natural volcanic glass with rich brown and black mahogany-like swirls created by iron oxide inclusions.