sedimentary

Jasper

Silicon dioxide (SiO2)

Hardness: 6.5-7 (Mohs scale); Color: Yellowish-brown to reddish-brown; Luster: Dull to waxy; Crystal structure: Microcrystalline/Cryptocrystalline; Cleavage: None (conchoidal fracture); Specific gravity: 2.58-2.91

Hardness: 6
Color: Yellowish-brown to reddish-brown
Luster: Dull to waxy

Identified April 23, 2026More sedimentary →

Identify your own rocks.

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

App Store Google Play

Physical properties

Formation & geological history

Usually formed from the deposition of silica from water-rich environments like hot springs or through the replacement of organic or volcanic materials. This specimen appears as a river-tumbled or water-worn nodule.

Uses & applications

Used primarily in lapidary arts for cabochons, beads, and carvings, as well as an ornamental stone and a collector specimen.

Geological facts

Jasper is an opaque variety of chalcedony. The presence of iron oxides like goethite or hematite gives it the earthen yellow and red tones seen here.

Field identification & locations

Identify in the field by its hardness (cannot be scratched by a steel blade), dull luster on unpolished surfaces, and smooth, rounded water-worn texture. Common in riverbeds and gravel deposits worldwide.