sedimentary

Breccia

Clastic breccia, likely fault breccia; composition varies, commonly quartz, feldspar, and lithic fragments cemented by silica or calcite

AI-generated identification · may be incorrect

Angular, poorly sorted fragments in a gray to pink-brown matrix; fragments retain sharp edges, distinguishing it from conglomerate. Typical hardness is about 6–7 for quartz-rich pieces, with dull to slightly vitreous luster and no consistent crystal structure or cleavage.

Identified September 16, 2026More sedimentary →

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At a glance

Common name: Breccia
Scientific name: Clastic breccia, likely fault breccia; composition varies, commonly quartz, feldspar, and lithic fragments cemented by silica or calcite
Category: sedimentary
Identified: September 16, 2026
Method: Standard

AI Estimated Value

Common building or field specimens: $5–$30; attractive polished or locality-labeled pieces: roughly $30–$150.

Not an official valuation

AI estimate for general interest only — not an appraisal. Actual value depends on condition, provenance, and market demand. Verify with a professional before buying, selling, or insuring.

This identification was generated by AI and may contain errors. Verify important details before relying on them — and never use an AI result to judge whether a specimen is safe to handle. Read the full disclaimer

Physical properties

Formation & geological history

Forms when broken rock fragments accumulate and become cemented, commonly along faults, volcanic vents, impact sites, or steep debris slopes. Its exact age cannot be determined from the image; it may range from Precambrian to recent.

Uses & applications

Used as dimension stone, paving, aggregate, and decorative architectural stone; attractive polished slabs may have modest ornamental value.

Geological facts

Breccia is defined primarily by angular clasts rather than a single mineral composition. Tectonic breccias can record fault movement, while volcanic and impact breccias preserve explosive or collision-related events.

Field identification & locations

Identify it by angular clasts of contrasting color and size in a cemented matrix; inspect a fresh surface and test individual grains for quartz hardness. Common worldwide, especially in fault zones, volcanic provinces, sedimentary basins, and impact structures.