mineral

Peacock Ore (Bornite or Chalcopyrite)

Bornite (Cu5FeS4) or Acid-Washed Chalcopyrite (CuFeS2)

AI-generated identification · may be incorrect

Hardness: 3-4 (Mohs); Color: Iridescent blues, purples, and golds; Luster: Metallic; Crystal Structure: Orthorhombic or Tetragonal; Specific Gravity: 4.1-5.3

Hardness: 3-4 (Mohs)
Color: Iridescent blues, purples, and golds
Luster: Metallic

Identified July 4, 2026More mineral →

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Physical properties

Hardness: 3-4 (Mohs); Color: Iridescent blues, purples, and golds; Luster: Metallic; Crystal Structure: Orthorhombic or Tetragonal; Specific Gravity: 4.1-5.3

Formation & geological history

Formed in hydrothermal veins and contact metamorphic zones, typically as a primary mineral in copper deposits. Natural tarnishing creates iridescent hues, though market specimens are often acid-treated.

Uses & applications

Major ore of copper; highly popular as a decorative mineral specimen for collectors and children.

Geological facts

While true Bornite naturally tarnishes to these colors, most bright specimens sold in shops are actually Chalcopyrite that has been treated with acid to force the colorful oxidation.

Field identification & locations

Identified by its intense metallic iridescence and dark gray/black streak. Found in major copper mining regions like Arizona (USA), Chile, and Mexico.