sedimentary

Polished brecciated jasper

Silicified breccia, chiefly microcrystalline quartz (SiO₂) with iron-oxide staining

AI-generated identification · may be incorrect

Typically Mohs 6.5–7; opaque brown, cream, gray, and rust-orange, with a waxy to vitreous polish. Irregular angular clasts are cemented by silica; no obvious cleavage, and specific gravity is about 2.5–2.7.

Identified August 28, 2026More sedimentary →

Explore Polished brecciated 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 preexisting silica-rich rock fragments are broken, deposited, and cemented by chalcedony or quartz, commonly during hydrothermal or volcanic activity. The exact geological age cannot be determined from the photograph and varies by locality.

Uses & applications

Used as a lapidary stone for cabochons, carvings, polished specimens, and ornamental objects; occasionally used as aggregate or decorative stone. This rounded specimen appears mainly collectible.

Geological facts

The contrasting angular fragments and pale silica veins are characteristic of brecciation, while orange areas likely contain hematite or limonite. It may sometimes be marketed under locality names such as brecciated jasper or picture jasper.

Field identification & locations

Identify it by its opaque, fine-grained silica body, hardness, conchoidal fracture, and inability to scratch with a steel knife; vinegar produces no reaction. Common sources include volcanic and hydrothermal regions worldwide, including the western United States, Mexico, Australia, and Madagascar.