Rock & Mineral Encyclopedia

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

Tiger Iron

A banded combination rock of golden tiger's eye, red jasper, and metallic hematite, formed in ancient iron deposits.

The principal iron ore, a heavy iron oxide ranging from metallic silver-gray to earthy red, always leaving a tell-tale red-brown streak.

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

The brassy iron sulfide mineral famous as 'fool's gold,' known for sharp metallic cubes and a much higher hardness than real gold.

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

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

An iron-rich orthopyroxene prized for its warm bronze schiller, a metallic-looking sheen created by tiny mineral inclusions.