sedimentary

Jasper

Jasper (Silicon Dioxide, SiO2)

Hardness: 6.5-7 (Mohs scale); Color: Variegated yellow, brown, and red; Luster: Vitreous to waxy; Crystal structure: Microcrystalline (Trigonal); Cleavage: None (Conchoidal fracture); Specific gravity: 2.58-2.91.

Hardness: 6
Color: Variegated yellow, brown, and red
Luster: Vitreous to waxy

Identified April 7, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed through the deposition of silica from volcanic ash or hydrothermal fluids in sedimentary environments. Its colors are derived from iron oxides and other mineral impurities incorporated during formation. It can be millions of years old, often found in ancient volcanic or marine limestone deposits.

Uses & applications

Used primarily for lapidary arts, jewelry (cabochons, beads), decorative carvings, and as a pocket stone or meditation tool for collectors.

Geological facts

The word 'Jasper' comes from the Greek word 'iaspis', meaning spotted stone. It is an opaque variety of chalcedony. Historically, it was a favorite gemstone in the ancient world, mentioned in many cultural texts including the Bible and ancient Egyptian lore.

Field identification & locations

Identify by its opacity (it does not transmit light even at the edges), its variegated earthy patterns, and its ability to scratch glass. It is commonly found globally, with significant deposits in India, Russia, Brazil, and the USA.