Rock & Mineral Encyclopedia

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

Cataclasite

A cohesive fault rock formed by brittle crushing and grinding of rock along a fault zone, with angular fragments in a fine matrix.

A black metallic manganese iron oxide famous for sharp cubic crystals, classically found with red beryl and topaz in Utah rhyolite.

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

A vivid green chromium-bearing diopside, an affordable emerald-like gem mined largely in Siberia.

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

A pale jasper threaded with black, fern-like mineral dendrites that mimic plants, trees, and frost despite being inorganic.