Rock & Mineral Encyclopedia

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

Dacite

A fine-grained volcanic rock intermediate between andesite and rhyolite, common at explosive stratovolcanoes.

A banded rhyolitic volcanic rock with swirling tan, red, and yellow iron-oxide layers prized as a decorative picture stone.

A black metallic manganese iron oxide famous for sharp cubic crystals, classically found with red beryl and topaz in Utah rhyolite.

A vivid pinkish-red rhodolite garnet named for its raspberry color, a bright pyrope-almandine blend popular in jewelry.

The classic deep-red garnet — usually almandine or pyrope — long worn as the fiery 'carbuncle' gem and January's birthstone.

A trademarked deep purple-red rhodolite garnet from India, named for its rich grape-like color from the pyrope-almandine series.

A bright strawberry-red garnet, typically an almandine-pyrope blend prized for its juicy, lively red color in jewelry.