Rock & Mineral Encyclopedia

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

Morimotoite

A black titanium garnet related to andradite and schorlomite, containing tetravalent titanium and ferrous iron, found in skarns and alkaline rocks.

A glassy, jet-black volcanic rock formed when lava cools too fast to crystallize, prized for razor-sharp conchoidal edges.

Black volcanic glass laced with delicate web-like veins of contrasting color, formed by flow banding and fine crystallization.

Black volcanic glass marked with rounded spots and patches that resemble a leopard's coat, caused by spherulitic crystallization.