mineral

Tumbled jasper, likely brown/red jasper

Microcrystalline quartz (chalcedony), SiO₂, colored by iron oxides

AI-generated identification · may be incorrect

Opaque reddish-brown material with a waxy to dull luster, irregular white weathering or quartz-rich areas, and a smoothly rounded tumbled surface. Hardness is about 6.5–7 Mohs; no visible cleavage; specific gravity approximately 2.6.

Identified September 11, 2026More mineral →

Explore Tumbled jasper, likely brown/red jasper in the encyclopedia →

Identify your own rocks.

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

App Store Google Play

Physical properties

Formation & geological history

Jasper forms when silica-rich fluids cement or replace volcanic ash, sediments, or fractured rock, with iron producing the red-brown color. Deposits occur in many ages, commonly in volcanic and sedimentary terrains.

Uses & applications

Used for cabochons, carvings, beads, tumbled stones, ornaments, and occasionally decorative architectural stone. Common pieces have modest collector value.

Geological facts

Its color and opacity distinguish it from clearer agate and crystalline quartz. The white patch may be quartz, chalcedony, or surface abrasion rather than a separate mineral.

Field identification & locations

Identify it by its dense opaque body, fine texture, red-brown iron staining, and inability to scratch it with a steel knife easily; a glass-scratch test can support identification. Common sources include India, Madagascar, Brazil, Australia, and the western United States.