Rock & Mineral Encyclopedia

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

Zincite

A rare zinc oxide best known for its deep red to orange color, classically from Franklin, New Jersey, and as colorful man-made crystals.

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

A brilliant orange-red lead vanadate mineral forming hexagonal crystals, prized by collectors and mined as an ore of vanadium.

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

A banded, metamorphosed iron formation in which bright red jasper alternates with silvery hematite or magnetite layers.

A striking rock of green zoisite studded with red-pink ruby crystals and black hornblende, also called anyolite.

Rhodochrosite is a rose-pink manganese carbonate prized for raspberry-red crystals and banded pink-and-white gem material.

A rare ferric-iron-dominant tourmaline that forms in oxidized evaporite settings, appearing as black to red-brown prismatic crystals.

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

A hollow rock nodule whose interior cavity is lined with inward-pointing crystals such as quartz, amethyst, or calcite.