Rock & Mineral Encyclopedia

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

Pelitic Schist

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

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.

Arizona Ruby is a chromium-rich pyrope garnet from Arizona, often gathered from anthills, valued for its intense ruby-like red.

A trademarked deep purple-red rhodolite garnet from India, named for its rich grape-like color from the pyrope-almandine series.