sedimentary

Brecciated Jasper (or Polished Sedimentary Breccia)

Breccia / Microcrystalline Quartz (SiO2)

AI-generated identification · may be incorrect

Hardness: 6.5 - 7 on Mohs scale; Color: mottled brown, tan, dark reddish-brown, and black; Luster: vitreous to waxy (high polish); Structure: composed of angular rock clasts cemented by a fine-grained siliceous or ferruginous matrix; Cleavage: none (conchoidal fracture).

Hardness: 6
Color: mottled brown, tan, dark reddish-brown, and black
Luster: vitreous to waxy (high polish)

Identified October 3, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed through mechanical fragmentation (faulting, volcanic activity, or sedimentary processes) where angular rock fragments are subsequently cemented together by silica-rich or mineral-rich fluids under pressure.

Uses & applications

Commonly carved and polished into decorative shapes such as eggs, spheres, and cabochons for mineral collectors, lapidary art, and metaphysical purposes.

Geological facts

Breccia differs from conglomerate primarily because its clasts are sharp and angular rather than rounded by water erosion, indicating they were cemented near where they broke.

Field identification & locations

Identifiable by its distinct mosaic-like pattern of angular fragment clasts bound in a fine matrix; widely found worldwide including the US, South Africa, Australia, and Brazil.