mineral

Unidentified dark mineral/rock fragment

Indeterminate; appearance may fit a sulfide-bearing rock or iron-rich mineral

AI-generated identification · may be incorrect

Small, irregular dark-brown to black fragment with yellow-gold patches and a likely earthy to submetallic luster. Hardness, cleavage, crystal structure, and specific gravity cannot be determined reliably from the image; the gold color could be pyrite, chalcopyrite, or staining.

Identified August 14, 2026More mineral →

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At a glance

Common name: Unidentified dark mineral/rock fragment
Scientific name: Indeterminate; appearance may fit a sulfide-bearing rock or iron-rich mineral
Category: mineral
Identified: August 14, 2026
Method: Standard

AI Estimated Value

Approximately $1–$20 as an unidentified small fragment; verified attractive pyrite or chalcopyrite specimens may sell for $10–$100+, depending on crystals and provenance.

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

Possibly formed by hydrothermal mineralization or weathering of an iron- and sulfide-bearing rock; geological age and formation environment are unknown.

Uses & applications

Typically a collecting specimen only unless confirmed as an ore mineral; sulfide minerals may be sources of copper, iron, or other metals.

Geological facts

Color alone cannot distinguish metallic gold from brassy sulfides. A streak test, hardness test, magnet test, density measurement, and close inspection of crystal faces are needed for identification.

Field identification & locations

Common possibilities include pyrite-bearing rock, chalcopyrite-bearing ore, or weathered limonite/goethite. Test streak on unglazed porcelain and avoid acid or destructive testing until identified; likely localities include hydrothermal veins and mining districts.