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

An earthy-toned jasper with vine-like or scenic patterning, valued by lapidaries for warm browns, reds, and creams that polish to a smooth finish.

A gray-toned jasper with swirling cream, black, and brown leaf-like patterns, sometimes with druzy or agate pockets.

A soft pink banded chalcedony, occurring naturally in delicate hues and also commonly produced by dyeing.

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

A banded variety of chalcedony quartz, classically black or black-and-white, long favored for cameos and beads.

A common coarse-grained intrusive rock like granite but richer in plagioclase than potassium feldspar.

A fine-grained volcanic rock intermediate between andesite and rhyolite, common at explosive stratovolcanoes.

An opaque blue variety of chalcedony jasper, less common than red or green forms, colored by mineral inclusions.

The most common sedimentary rock, a fissile mudrock of compacted clay and silt that splits into thin layers.