Rock & Mineral Encyclopedia

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

Flame Jasper

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

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

A black-and-white striped chalcedony-quartz rock whose bold zebra-like banding makes it a popular ornamental and lapidary stone.

A common opal containing moss- or fern-like mineral inclusions that resemble plants suspended in a pale silica body.

Ancient wood whose organic tissue has been replaced by silica, preserving the grain, rings, and structure of the original tree in stone.

A translucent, soft blue variety of microcrystalline quartz whose color comes from light scattering through its fine structure.