Rock & Mineral Encyclopedia

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

Fluorite

A soft, colorful calcium fluoride mineral famous for cubic crystals, perfect octahedral cleavage, and fluorescence under UV light.

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

A soft, pastel minty-green tourmaline prized for its fresh, light color, a delicate variety of green elbaite.