Rock & Mineral Encyclopedia

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

Black Agate

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

A green-hued banded chalcedony, ranging from natural soft greens to brightly dyed commercial stones.

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

A banded chalcedony agate with bold alternating dark and light stripes resembling zebra markings, sometimes color-enhanced.

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

A bold black-and-white banded chalcedony named for its orca-like coloring, popular as carvings and statement jewelry.

A soft peachy-orange variety of banded chalcedony, naturally iron-tinted or dyed, popular for warm-toned beads and jewelry.

A banded variety of chalcedony quartz, classically black or black-and-white, long favored for cameos and beads.

A vivid yellow-and-black banded stone from Indonesian volcanic vents, colored by sulfur, arsenic minerals and iron oxides, not true jasper.

A black volcanic glass threaded with delicate grey, swirling lace-like bands of flow lines that show beautifully when polished.