sedimentary

Jasper

Silicon dioxide (SiO2) with impurities

Hardness: 6.5-7 (Mohs scale), Color: Brown/Yellow/Black patterns, Luster: Vitreous to dull, Crystal Structure: Microcrystalline (Trigonal), Cleavage: None, Fracture: Conchoidal

Hardness: 6

Identified April 28, 2026More sedimentary →

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 scale), Color: Brown/Yellow/Black patterns, Luster: Vitreous to dull, Crystal Structure: Microcrystalline (Trigonal), Cleavage: None, Fracture: Conchoidal

Formation & geological history

Formed through the accumulation of fine volcanic ash or silica-rich sediments in hydrothermal or sedimentary environments, often solidified through chemical precipitation.

Uses & applications

Used primarily in lapidary arts, jewelry (cabochons), interior decoration, and as a popular collector's stone due to unique patterns.

Geological facts

Jasper is an opaque variety of chalcedony. The name comes from the Greek word 'iaspis', meaning 'spotted stone'. No two pieces are ever truly identical due to the complex impurity layering.

Field identification & locations

Identify in the field by its hardness (will scratch glass), opacity, and smooth, waxy surface when polished or wet. Common in riverbeds and mountainous regions globally.