mineral

Copper-bearing rock, likely bornite/chalcopyrite in iron-rich matrix

Chalcopyrite (CuFeS₂) and/or bornite (Cu₅FeS₄) in limonite/goethite matrix

AI-generated identification · may be incorrect

Metallic brassy-gold to bronze sulfide patches occur in a dark red-brown, earthy iron-oxide matrix; sulfides are typically Mohs 3.5–4, with indistinct cleavage and metallic luster, while the matrix is softer and dull. The apparent green-blue coating may be copper oxidation products such as malachite or chrysocolla.

Identified August 26, 2026More mineral →

Explore Copper-bearing rock, likely bornite/chalcopyrite in iron-rich matrix in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

At a glance

Common name: Copper-bearing rock, likely bornite/chalcopyrite in iron-rich matrix
Scientific name: Chalcopyrite (CuFeS₂) and/or bornite (Cu₅FeS₄) in limonite/goethite matrix
Category: mineral
Identified: August 26, 2026
Method: Standard

AI Estimated Value

About $5–$25 for a small ordinary specimen; $30–$100+ if naturally iridescent, well-crystallized, or locality-labeled.

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

Formed in hydrothermal copper-ore veins or disseminated deposits, commonly by sulfide mineralization followed by near-surface oxidation; age depends on locality and cannot be determined from the image.

Uses & applications

Primarily an ore and teaching/collecting specimen; chalcopyrite is a major copper source, while attractive pieces may be sold as mineral specimens rather than used as gemstones.

Geological facts

Bornite is called “peacock ore” when iridescent; copper sulfides can tarnish to blue, green, purple, or bronze colors, though artificial peacock ore is also common.

Field identification & locations

Look for brassy metallic grains, dark streak, moderate heft, and possible green copper staining; confirm with streak, hardness, specific gravity, and ideally chemical or X-ray testing. Common in copper districts worldwide, including Arizona, Montana, Peru, and Cornwall.