Rock & Mineral Encyclopedia

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

Electric Blue Obsidian

Obsidian with a vivid blue sheen or hue; natural blue obsidian is rare, and intensely uniform blue material is usually manufactured glass.

A transparent to milky opal that displays a soft bluish-white internal glow or sheen that seems to follow the light source.

The colorless to milky-white variety of beryl, known mineralogically as goshenite and once used to imitate diamond and other gems.

A rare emerald showing a six-spoked star pattern of dark inclusions, named after the spokes of a sugar-mill wheel.