Rock & Mineral Encyclopedia

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

Sesame Jasper

A finely speckled pale jasper trade stone named for its sesame-seed-like flecks, closely related to Kiwi Jasper.

A dark green chalcedony speckled with blood-red spots of iron oxide, traditionally known as heliotrope.

A dark green jasper-chalcedony speckled with red iron-oxide spots, classically known as bloodstone or heliotrope.

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

A dark jasper trade stone speckled with pale flecks resembling a starry night sky, valued for its cosmic appearance.

Fossilized tree resin, warm and lightweight, sometimes preserving ancient insects and plant matter inside.

A man-made opalescent glass that glows milky blue in reflected light and warm orange when backlit, often sold as a crystal.

A high-grade metamorphic rock defined by alternating light and dark mineral bands, formed under intense heat and pressure.

A dark green-and-black stromatolite jasper patterned with swirling orbs, formed from fossilized ancient microbial colonies.

A precious opal pattern made of tiny, densely packed pinpoint flashes of play-of-color, like sparkling speckles across the stone.

A jasper crossed by fine dark veins forming a spiderweb-like network, often a brecciated stone cemented by darker matrix.