sedimentary

Polished orbicular jasper

Orbicular jasper; microcrystalline quartz (SiO₂) with hematite/goethite and other silicate inclusions

AI-generated identification · may be incorrect

Hardness about 6.5–7 Mohs; opaque tan, cream, brown, gray, and black orbicular patterns; vitreous to waxy luster when polished; cryptocrystalline, with no visible cleavage and conchoidal fracture. The specimen appears polished and possibly stabilized or resin-filled.

Identified August 10, 2026More sedimentary →

Explore Polished orbicular 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

Forms when silica-rich fluids replace volcanic ash or other host rock, producing concentric mineral growths and brecciation; commonly Paleozoic to Cenozoic, depending on locality. Orbicular jasper occurs in volcanic and hydrothermal environments.

Uses & applications

Used for cabochons, spheres, carvings, beads, and decorative objects; prized primarily as a lapidary and collecting material rather than for industrial construction.

Geological facts

Its distinctive “orb” or eye-like patterns result from concentric shells of quartz and iron-bearing minerals around nuclei. Similar material is sold under locality names such as ocean jasper, leopard jasper, or poppy jasper, though trade names can overlap.

Field identification & locations

Identify it by the polished surface, opaque silica-rich body, and repeated rounded orbicular spots; it should scratch glass but not be scratched by a steel knife. Common sources include Madagascar, Mexico, Australia, and the western United States.