Rock & Mineral Encyclopedia

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

Imperial Garnet

A trade name for high-brilliance golden grossular-andradite (grandite) garnet, most associated with the Mali deposits of West Africa.

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

Molybdenite is the primary ore of molybdenum, a soft, greasy, silver-gray sulfide that closely resembles graphite.

Grandite is an intermediate garnet between grossular and andradite, common in skarns and prized for vivid green to golden crystals.

A rare grossular-andradite blend ('grandite') from Mali, prized for its high brilliance and golden-green to yellow color.

A celebrated plume agate from the Oregon-Idaho border, known for dramatic black, gold, and red plumes in clear chalcedony.