sedimentary

Jasper

Silicon dioxide (SiO2)

AI-generated identification · may be incorrect

Hardness: 6.5-7 (Mohs); Color: Red, brown, yellow, and tan; Luster: Dull to waxy; Structure: Microcrystalline; Cleavage: None (conchoidal fracture); Opaque.

Hardness: 6
Color: Red, brown, yellow, and tan
Luster: Dull to waxy

Identified July 6, 2026More sedimentary →

Explore Jasper in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Hardness: 6.5-7 (Mohs); Color: Red, brown, yellow, and tan; Luster: Dull to waxy; Structure: Microcrystalline; Cleavage: None (conchoidal fracture); Opaque.

Formation & geological history

Formed from silica-rich fluids permeating volcanic or sedimentary rocks, often resulting from the replacement of original materials. Most specimens found on surfaces are from the Cenozoic or Mesozoic eras.

Uses & applications

Used primarily for lapidary work, jewelry (cabochons), tumbled stones, and as ornamental landscaping rock.

Geological facts

Jasper is a variety of chalcedony. Its patterns and colors are caused by impurities such as iron oxides. The name 'Jasper' is derived from a Greek word meaning 'spotted stone'.

Field identification & locations

Identify by its hardness (cannot be scratched by a knife), smooth texture, and colorful opaque patterns. Common in riverbeds and gravel deposits worldwide.