mineral

Likely weathered quartz-rich rock, possibly smoky quartz or chert

Quartz (SiO₂), though exact identification is uncertain from the photograph

AI-generated identification · may be incorrect

Dark gray-brown, irregular and partly translucent with a vitreous-to-dull luster; quartz hardness is Mohs 7, lacks cleavage, and has conchoidal fracture. The rough surface may include iron-oxide staining or attached matrix.

Identified August 11, 2026More mineral →

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At a glance

Common name: Likely weathered quartz-rich rock, possibly smoky quartz or chert
Scientific name: Quartz (SiO₂), though exact identification is uncertain from the photograph
Category: mineral
Identified: August 11, 2026
Method: Standard

AI Estimated Value

Approximately $1-$10 as a common rough fragment; potentially $10-$50+ if translucent, unusually colored, or locally significant.

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

Quartz forms in igneous, hydrothermal, and sedimentary environments over a wide range of geological ages; brown coloration commonly results from inclusions, irradiation, or iron staining.

Uses & applications

Common quartz is used in glass, ceramics, abrasives, electronics, and construction; attractive transparent pieces may be cut as gemstones or kept as specimens.

Geological facts

A steel file or glass-scratch test can help distinguish quartz from softer minerals, but testing may damage the specimen. The image does not show diagnostic crystal faces, so a more specific identification is not reliable.

Field identification & locations

Common worldwide in veins, granites, pegmatites, and river gravels; inspect for conchoidal fracture, lack of cleavage, and ability to scratch glass. A streak, hardness test, and close-up inspection would improve identification.