Rock & Mineral Encyclopedia

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

Clear Obsidian

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

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

A naturally magnetic black iron oxide and a major iron ore; strongly magnetic specimens are known as lodestone.

A striking lead chromate mineral prized for its brilliant orange-red prismatic crystals, with the finest specimens from Tasmania.

The golden-yellow variety of quartz, ranging from pale lemon to deep madeira amber, often produced by heating amethyst.