Rock & Mineral Encyclopedia

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

Jade

A tough, prized ornamental gem that is actually two distinct minerals, jadeite and nephrite, revered for millennia in many cultures.

A green ornamental stone, often serpentine-rich marble or verde antique, valued for its rich green color and white veining.

A hard aluminum borosilicate famous for its rich denim-blue color, often forming dense fibrous masses or coloring quartz blue.

An opaque, porcelain-white common opal prized for its milky, pearl-like appearance and high porosity, often carved or beaded.

A deep black variety of banded chalcedony, often closely related to or treated like onyx, used for jewelry and carvings.

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

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

A trade name occasionally used for golden-yellow beryl (golden beryl or heliodor), the iron-colored yellow variety of the emerald mineral.

A common opal containing dendritic or mossy mineral inclusions that form miniature landscape-like scenes inside the stone.

A metamorphic rock of calcium-rich silicate minerals formed from impure limestone or dolomite altered by heat and fluids.

An old name for a dull leek-green variety of quartz or chalcedony colored by green mineral inclusions, historically called mother of emerald.