gemstone

Polished brecciated jasper

Jasper, an opaque microcrystalline quartz variety (SiO₂), with iron-oxide and other mineral inclusions

AI-generated identification · may be incorrect

Hardness about 6.5–7 Mohs; cream, tan, blue-gray, and reddish-brown mottling with a glossy polished luster. It is cryptocrystalline, opaque, and has no visible cleavage; density is typically 2.5–2.7.

Identified August 24, 2026More gemstone →

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Physical properties

Formation & geological history

Forms when silica-rich groundwater cements and replaces volcanic ash, sediments, or fractured rock, producing brecciation and multicolored patterns. Individual pieces may range from Paleozoic to Cenozoic depending on locality.

Uses & applications

Used for cabochons, worry stones, carvings, beads, and decorative objects; occasionally as ornamental tile or small aggregate. Value is mainly aesthetic rather than commercial.

Geological facts

The specimen appears tumbled or polished, with angular color patches and dark iron-oxide-rich seams characteristic of brecciated jasper. Exact identification from a photograph is approximate.

Field identification & locations

Look for an opaque stone with smooth waxy-to-glassy polish, irregular patterns, and no translucent quartz crystals; it should resist scratching by a steel knife. Common sources include Oregon, California, Utah, Madagascar, Brazil, and Australia.