Rock & Mineral Encyclopedia

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

Chrysocolla

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

A copper-iron sulfide ore famous for its iridescent peacock-like purple and blue tarnish; often sold as treated chalcopyrite.

A rare, intensely blue chalcedony colored by copper-rich chrysocolla, prized as the most valuable of the blue chalcedonies.

A brassy copper-iron sulfide that is the world's most important copper ore, often showing colorful iridescent tarnish.

A copper iron sulfide famous for its vivid iridescent purple-blue tarnish, the classic peacock ore and a copper ore.

Cuprite is a deep red copper oxide and an important secondary copper ore, prized for its rare ruby-red gem crystals.

A dark gray copper sulfide that is one of the richest copper ores, prized by collectors when found as rare sharp crystals.

A rare deep-blue copper silicate mineral, often fibrous or massive, named for the Shattuck Mine in Arizona and prized by collectors.

A vivid green copper carbonate mineral famous for swirling concentric bands, used as an ore of copper and an ornamental gemstone.

A gray copper-antimony sulfosalt of the fahlore group, an important ore of copper and often silver, forming tetrahedral crystals.

A deep blue copper carbonate mineral that forms in oxidized copper deposits, often alongside green malachite.

A pale copper-red nickel arsenide, historically called kupfernickel, that is an ore of nickel and gives the metal its name.

A vivid copper-bearing Mexican stone of red cuprite and green chrysocolla that evokes a desert sunset.

A copper-bearing labradorite feldspar from Oregon, famous for its range of natural colors and glittery aventurescent copper schiller.

A feldspar gemstone that sparkles with metallic glints (aventurescence) caused by tiny reflective copper or hematite platelets.