mineral

Peacock Ore

Bornite (Cu5FeS4) or Chalcopyrite treated with acid

Hardness: 3 on Mohs scale; Color: Iridescent blue, purple, green, and gold; Luster: Metallic; Crystal Structure: Orthorhombic/Tetragonal; Cleavage: Poor; Specific Gravity: 5.06-5.08

Hardness: 3 on Mohs scale
Color: Iridescent blue, purple, green, and gold
Luster: Metallic

Identified June 9, 2026More mineral →

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Physical properties

Hardness: 3 on Mohs scale; Color: Iridescent blue, purple, green, and gold; Luster: Metallic; Crystal Structure: Orthorhombic/Tetragonal; Cleavage: Poor; Specific Gravity: 5.06-5.08

Formation & geological history

Formed in hydrothermal veins, contact metamorphic zones, and as a primary mineral in igneous rocks. While bornite is naturally iridescent, many commercial 'peacock ore' specimens are chalcopyrite that has been acid-washed to induce tarnish.

Uses & applications

Major ore of copper; widely collected as a decorative mineral specimen and used in metaphysical practices.

Geological facts

Natural Bornite is often called 'peacock ore' because it tarnishes to iridescent shades of blue and purple. It is approximately 63% copper by mass.

Field identification & locations

Identify in the field by its metallic luster and the vibrant, multi-colored tarnish. Unlike natural bornite which is dark, commercial peacock ore is often brighter and based on yellow chalcopyrite. It is found in copper mines worldwide, notably in Mexico and the USA.

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