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 Jasper

A dense, opaque black variety of microcrystalline quartz historically used as a touchstone for testing precious metals.

A rare Australian jasper from the Pilbara with bold red, yellow, and black abstract patterns, prized by collectors.

An opaque brown chalcedony whose iron-stained banding mimics deserts, dunes, and distant mountain skylines.

A microcrystalline quartz jasper marked by small concentric ring or eye patterns that resemble the eyes of birds.

Ancient chemically deposited rock of alternating iron-oxide and silica bands recording Earth's early oxygenation and a major iron ore source.