Rock & Mineral Encyclopedia

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

Green Beryl

Light green beryl colored mainly by iron, distinguished from emerald, which owes its deeper green to chromium or vanadium.

A general term for light-colored, fine-grained volcanic rocks rich in quartz and feldspar, like rhyolite.

Black volcanic glass that flashes flame-like bands of iridescent color when light strikes aligned nanoscale inclusions.

The red to raspberry-pink variety of tourmaline, prized for its vivid ruby-like color that holds under both daylight and artificial light.