Rock & Mineral Encyclopedia

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

Suevite

A rare breccia formed by meteorite impact, containing shocked rock fragments and glassy melt blobs welded together.

A limestone packed with visible shells and shell fragments, recording the accumulation of marine invertebrate remains on ancient sea floors.

A jasper made of angular fragments naturally cemented back together, typically showing red and brown pieces in a quartz matrix.

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

A marketing name for red beryl, the rare manganese-colored beryl from Utah, evoking emerald to convey its prestige and rarity.

An exceptionally rare red variety of beryl colored by manganese, found chiefly in Utah and prized as one of the rarest gems.

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