metamorphic

Likely mafic metamorphic rock with sulfide mineralization

Probable amphibolite or hornblende–biotite schist, locally bearing pyrite/other sulfides

AI-generated identification · may be incorrect

Dark gray-green, coarse crystalline, weakly foliated rock with pale veins or alteration and brassy metallic grains. Likely hardness 5–6 overall; sulfides may be softer or brittle, with variable luster and no obvious cleavage at specimen scale.

Identified September 8, 2026More metamorphic →

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At a glance

Common name: Likely mafic metamorphic rock with sulfide mineralization
Scientific name: Probable amphibolite or hornblende–biotite schist, locally bearing pyrite/other sulfides
Category: metamorphic
Identified: September 8, 2026
Method: Standard

AI Estimated Value

About $5–$30 as an ordinary hand specimen; $30–$100+ if sulfide mineralization is attractive, demonstrable, and locality-documented.

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

Probably formed when basaltic or gabbroic protolith was metamorphosed under medium-grade conditions, with later hydrothermal fluids depositing sulfides and light-colored minerals. Exact age and identification require thin-section or chemical testing.

Uses & applications

Unaltered material has limited construction value; sulfide-bearing specimens may interest collectors or ore-mineral enthusiasts. It is not identifiable as a gemstone from the photograph.

Geological facts

Brassy grains could be pyrite, chalcopyrite, or pyrrhotite, while white material may be quartz or calcite. A streak, magnetism test, acid test, and close examination of cleavage would help distinguish them.

Field identification & locations

Commonly associated with metamorphic belts and altered mafic rocks; similar specimens occur worldwide. Look for foliation, amphibole crystals, metallic sulfides, and reaction to magnet or dilute hydrochloric acid, but visual identification is provisional.