Rock & Mineral Encyclopedia

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

Bumblebee Jasper

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

Fossilized wood in which the original organic structure has been replaced by opal, sometimes showing precious play-of-color.

An opal cut to show chatoyancy, a sharp moving band of light like a cat's eye, usually in honey, green or yellow common opal.

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

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

Small ironstone concretions from Yowah, Queensland, whose hollow or veined centers hold brilliant precious boulder opal.