mineral

Tumbled brown jasper

Microcrystalline quartz (SiO₂), commonly called jasper when opaque and impurity-colored

AI-generated identification · may be incorrect

Smooth, opaque brown stone with a polished luster; quartz hardness is about 7 Mohs, with no visible cleavage and a trigonal crystal structure at the microscopic scale. The photograph does not allow definitive identification; other brown stones may look similar.

Identified October 16, 2026More mineral →

Explore Tumbled brown 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 as silica-rich fluids fill cavities or replace material in rocks, with iron oxides and other impurities producing color. Its geological age and exact source cannot be determined from the image.

Uses & applications

Tumbled jasper is used in jewelry, ornaments, and lapidary collections; it has little industrial use as a polished pebble.

Geological facts

Jasper is a variety of chalcedony, itself a microcrystalline form of quartz; the name describes an appearance rather than a single precise composition.

Field identification & locations

Typical jasper is opaque, takes a good polish, and may show mottling or bands. A scratch test or mineralogical analysis would help distinguish it from other brown pebbles; source locations are widespread.