Rock & Mineral Encyclopedia

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

Flame Obsidian

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

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

Fine acicular (needle-like) tourmaline crystals, often black schorl, frequently seen as slender inclusions within clear quartz.

A black volcanic glass threaded with delicate grey, swirling lace-like bands of flow lines that show beautifully when polished.