sedimentary

Jasper

Silicon Dioxide (SiO2) with impurities

Hardness: 6.5-7 (Mohs scale); Color: Red, brown, yellow, or green (often mottled); Luster: Vitreous to dull; Crystal Structure: Microcrystalline (Trigonal); Cleavage: None; Specific Gravity: 2.58-2.91

Hardness: 6
Color: Red, brown, yellow, or green (often mottled)
Luster: Vitreous to dull

Identified March 11, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed through the deposition of silica-rich fluids within cracks or volcanic ash, typically in sedimentary environments where iron oxides and other minerals provide pigmentation. It can range from Precambrian to recent geological ages.

Uses & applications

Primarily used for lapidary work, jewelry (cabochons, beads), decorative ornaments, and as a popular specimen for crystal collecting and metaphysical purposes.

Geological facts

Jasper is an opaque variety of chalcedony. The name 'Jasper' is derived from the Greek word 'iaspis', meaning 'spotted stone.' Many varieties are named after their appearance, such as 'Ocean Jasper' or 'Leopard Skin Jasper.'

Field identification & locations

Identify in the field by its opacity (it does not transmit light even on thin edges), its smooth conchoidal fracture, and extreme hardness. Common locations include India, Brazil, Madagascar, and the United States (specifically Oregon and Idaho).