Rock & Mineral Encyclopedia

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

Danburite

A glassy calcium borosilicate forming wedge-tipped prismatic crystals, usually colorless to pale yellow or pink, sometimes faceted as a gem.

A prized Idaho jasper known for porcelain-smooth pastel pinks, creams, and greens in soft swirling, orbicular patterns.

A vivid blue-green hydrated copper silicate, soft on its own but prized as a gem when hardened by intergrown quartz or chalcedony.

An opaque blue variety of chalcedony jasper, less common than red or green forms, colored by mineral inclusions.

A prized Mexican jasper known for pastel green, lavender, and cream orbicular patterns that take an exceptional polish.

Tourmaline crystals displaying two or more distinct colors at once, including the famous pink-and-green watermelon variety.

A group of silicate gemstones best known for deep red but spanning nearly every color, including green tsavorite and orange spessartine.