sedimentary

Polished brecciated jasper or iron-rich chert

Silica-rich microcrystalline quartz (SiO₂), with iron-oxide/hydroxide staining; exact identification requires testing

AI-generated identification · may be incorrect

Brown, tan, cream, and reddish-gold mottling with a waxy to dull luster and irregular brecciation. Quartz hardness is about 6.5–7 Mohs; no obvious cleavage, with conchoidal fracture and typically opaque, compact texture.

Identified August 22, 2026More sedimentary →

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At a glance

Common name: Polished brecciated jasper or iron-rich chert
Scientific name: Silica-rich microcrystalline quartz (SiO₂), with iron-oxide/hydroxide staining; exact identification requires testing
Category: sedimentary
Identified: August 22, 2026
Method: Standard

AI Estimated Value

About $5–$30 for a small common piece; $30–$100+ for an attractive polished or unusual-quality specimen.

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 from microcrystalline silica deposited or replacing preexisting sediment, later fractured and cemented, with iron minerals producing the golden-brown colors. Such materials commonly formed in sedimentary or volcanic settings over broad geologic timescales.

Uses & applications

Used as lapidary material for cabochons, carvings, beads, and decorative polished specimens; occasionally used as a minor ornamental stone. Value is primarily aesthetic and depends on pattern, polish, size, and locality.

Geological facts

The specimen appears naturally geological but may be cut or polished. Golden coloration can result from limonite or goethite rather than metallic gold.

Field identification & locations

Identify with a glass-scratch test, conchoidal fracture, and absence of fizz in dilute acid; a streak or specific-gravity test helps distinguish jasper from softer calcite or slag. Common examples occur in the western United States, Australia, Brazil, and Africa.