sedimentary

Jasper

Silicon dioxide (SiO2)

AI-generated identification · may be incorrect

Hardness: 6.5-7 (Mohs); Color: Red, brown, and grey patterns; Luster: Dull to greasy; Crystal Structure: Microcrystalline quartz; Cleavage: None, conchoidal fracture

Hardness: 6
Color: Red, brown, and grey patterns
Luster: Dull to greasy

Identified June 21, 2026More sedimentary →

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Physical properties

Hardness: 6.5-7 (Mohs); Color: Red, brown, and grey patterns; Luster: Dull to greasy; Crystal Structure: Microcrystalline quartz; Cleavage: None, conchoidal fracture

Formation & geological history

Formed through the precipitation of silica-rich fluids within volcanic ash or sedimentary beds, often during the Cretaceous period. The red hues are caused by iron inclusions.

Uses & applications

Used primarily as a gemstone in jewelry, for lapidary arts like cabochons, and as decorative ornamental stone.

Geological facts

Jasper is an opaque variety of chalcedony. The word 'jasper' means 'spotted or speckled stone' and it has been used for talismans and jewelry for thousands of years.

Field identification & locations

Identify in the field by its opacity, hardness (will scratch glass), and smooth, waxy fracture surfaces. Commonly found in riverbeds and desert environments.