Rock & Mineral Encyclopedia

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

Citrine

The golden-yellow variety of quartz, ranging from pale lemon to deep madeira amber, often produced by heating amethyst.

An opaque yellow-to-golden variety of jasper, an iron-stained microcrystalline quartz prized for warm color and durable polish.

A vivid greenish-yellow quartz, usually heat-treated or irradiated, prized for its clean clarity and bright lemon color.

A natural bicolor quartz that combines purple amethyst and golden citrine in a single crystal.

Rose quartz that displays a six-rayed star (asterism) when cut as a cabochon, caused by microscopic rutile-like inclusions.

A warm orange-to-red variety of chalcedony quartz colored by iron oxide, used since antiquity for seals, beads, and cabochons.

A solid jet-black chalcedony, usually a dyed and treated agate, prized for sleek polished beads, cabochons, and intaglios.

A fiery jasper whose red, orange, and yellow plumes lick across the stone like flames against an earthy background.

A pale green variety of quartz, usually created by heat-treating amethyst, often marketed as green amethyst.

A chalcedony agate with red, orange, and yellow plume or banding patterns that rise like dancing flames within the stone.

An earthy-toned jasper with vine-like or scenic patterning, valued by lapidaries for warm browns, reds, and creams that polish to a smooth finish.

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

An opaque green variety of chalcedony quartz colored by iron and chlorite-group inclusions, prized as a durable carving and cabochon stone.