Rock & Mineral Encyclopedia

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

Purple Opal

A purple-hued common opal, much of it the Mexican "morado" type, valued for even violet color rather than play-of-color.

The pure colorless variety of beryl, valued as crystal specimens and as a brilliant alternative to clearer gemstones.

An unusually pure, transparent-to-translucent obsidian with few inclusions; truly water-clear specimens are rare in nature.

Transparent, colorless beryl (goshenite), the pure form of the species valued for its clarity, hardness, and well-formed crystals.