sedimentary

Reddish-brown fine-grained rock (likely jasper or iron-stained chert)

Microcrystalline quartz, SiO₂, with iron-oxide staining; exact identification is uncertain from the photo

AI-generated identification · may be incorrect

Opaque, reddish-brown with pale veins or weathered patches and a dull to slightly waxy surface. Quartz has Mohs hardness 7 and trigonal crystal structure; the specimen shows no visible cleavage and likely breaks with irregular or conchoidal fracture.

Identified October 16, 2026More sedimentary →

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At a glance

Common name: Reddish-brown fine-grained rock (likely jasper or iron-stained chert)
Scientific name: Microcrystalline quartz, SiO₂, with iron-oxide staining; exact identification is uncertain from the photo
Category: sedimentary
Identified: October 16, 2026
Method: Standard

AI Estimated Value

About $1–$10 for a small, common rough specimen; more if testing confirms attractive jasper suitable for lapidary work.

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

If jasper or chert, it formed as silica-rich sediment or replacement in sedimentary rocks, with iron oxides supplying the color. Such material forms across many geological ages and settings.

Uses & applications

Similar material is used for carvings, beads, cabochons, and decorative stone; this small rough piece has little apparent commercial value.

Geological facts

Jasper is an opaque variety of chalcedony, while chert is a broader term for fine-grained silica rock; color alone cannot distinguish them reliably.

Field identification & locations

Look for hardness near 7, lack of cleavage, and a conchoidal fracture; a scratch or streak test can help, but the photo is insufficient for a firm ID. Chert and jasper occur worldwide in sedimentary settings.