mineral

Brecciated jasper/chalcedony (iron-stained silica)

Microcrystalline quartz, SiO₂, with iron-oxide inclusions

AI-generated identification · may be incorrect

Hardness about 6.5–7 Mohs; brown, honey, black, gray, and reddish colors; vitreous to waxy luster; opaque to translucent; no obvious cleavage and irregular/conchoidal fracture. The angular fragments and silica cement indicate brecciation.

Identified August 10, 2026More mineral →

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Physical properties

Formation & geological history

Likely formed when silica-rich fluids filled and cemented fractures in older volcanic or sedimentary rock, with later iron oxidation producing the red-brown colors; age depends on locality and cannot be determined from the photograph.

Uses & applications

Used as ornamental stone, cabochons, beads, carvings, lapidary slabs, and mineral-collection specimens; too irregular for most architectural construction.

Geological facts

The specimen appears to combine jasper, chalcedony, and possibly quartz vein material rather than a single pure mineral. A steel file should barely scratch it, while it can scratch ordinary glass.

Field identification & locations

Identify by its high hardness, silica-like fracture, waxy/glassy surfaces, and angular multicolored fragments; common in hydrothermal veins, volcanic terrains, and gravel deposits worldwide. Acid produces no reaction, distinguishing it from calcite-rich rocks.