Rock & Mineral Encyclopedia

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

Jaspillite

A banded, metamorphosed iron formation in which bright red jasper alternates with silvery hematite or magnetite layers.

A 'mixed rock' showing swirling light and dark bands, formed where high-grade metamorphism causes rock to begin partially melting.

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

A transparent to milky opal that displays a soft bluish-white internal glow or sheen that seems to follow the light source.

The colorless to milky-white variety of beryl, known mineralogically as goshenite and once used to imitate diamond and other gems.

A green ornamental stone, often serpentine-rich marble or verde antique, valued for its rich green color and white veining.

A magnesium carbonate mineral, usually chalky white with grey veining, widely dyed to imitate turquoise and other stones.

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

A royal-blue feldspathoid mineral with white calcite veining, often confused with lapis lazuli but lacking its golden pyrite flecks.

A prized blue to blue-green copper-aluminium phosphate, often veined with dark matrix, treasured for jewelry across many cultures.

A rare emerald showing a six-spoked star pattern of dark inclusions, named after the spokes of a sugar-mill wheel.