Rock & Mineral Encyclopedia

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

Green Agate

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

A yellow to golden banded chalcedony colored by iron, ranging from natural honey tones to dyed commercial stones.

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

Abundant banded chalcedony from southern Brazil, the world's main source of agate slices and dyed agate products.

A purple-toned banded chalcedony, sometimes naturally amethystine but frequently produced by dyeing gray agate.

A soft pink banded chalcedony, occurring naturally in delicate hues and also commonly produced by dyeing.

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

A red-toned banded chalcedony colored by iron oxides, ranging from natural carnelian-like reds to heat-treated stones.

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

A white to grayish banded chalcedony, the natural base color of much agate and the substrate for many dyed stones.

A treated chalcedony with a network of crackled veins, usually heated and dyed in vivid colors for affordable, eye-catching beads.

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