mineral

Polished brown chalcedony or jasper

Microcrystalline quartz (SiO₂), likely iron-stained chalcedony/jasper with vugs

AI-generated identification · may be incorrect

Hardness about 6.5–7 Mohs; reddish-brown to orange-brown, waxy to dull luster, cryptocrystalline quartz, and irregular cavities lined or filled with pale mineral material. The rounded shape appears naturally water-worn or tumbled.

Identified September 5, 2026More mineral →

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At a glance

Common name: Polished brown chalcedony or jasper
Scientific name: Microcrystalline quartz (SiO₂), likely iron-stained chalcedony/jasper with vugs
Category: mineral
Identified: September 5, 2026
Method: Standard

AI Estimated Value

Typically $5–$30 for a small common polished specimen; attractive patterning, unusual cavity fillings, or confirmed locality can raise value to roughly $40–$100.

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

Likely formed when silica-rich fluids filled or replaced volcanic rock, with iron oxides producing the brown-red color; cavities may preserve former gas bubbles or weathered inclusions. Exact age and locality cannot be determined from the photograph.

Uses & applications

Used as a lapidary stone for cabochons, carvings, polished specimens, and inexpensive jewelry; jasper is also used decoratively and occasionally in architecture.

Geological facts

The specimen may be brecciated jasper or vuggy chalcedony rather than a single precise variety. A streak, hardness, and close examination of the cavities would improve identification.

Field identification & locations

Commonly found in volcanic terrains, especially silica-rich lava flows and hydrothermal veins. It should scratch ordinary glass but not be scratched by a steel knife; fizzing in dilute acid would suggest carbonate material instead.