mineral

Pyrite (Iron Pyrite)

Iron Disulfide (FeS2)

Hardness: 6-6.5 Mohs scale; Color: Pale brass-yellow to darker metallic grey; Luster: Metallic; Crystal Structure: Isometric (cubic, pyritohedron); Cleavage: Indistinct; Specific Gravity: 4.9-5.2

Hardness: 6-6
Color: Pale brass-yellow to darker metallic grey
Luster: Metallic

Identified April 5, 2026More mineral →

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Physical properties

Hardness: 6-6.5 Mohs scale; Color: Pale brass-yellow to darker metallic grey; Luster: Metallic; Crystal Structure: Isometric (cubic, pyritohedron); Cleavage: Indistinct; Specific Gravity: 4.9-5.2

Formation & geological history

Formed in high and low temperature hydrothermal veins, as an accessory mineral in igneous rocks, and in sedimentary rocks (shales and coals) through the interaction of iron and sulfur in anaerobic environments.

Uses & applications

Historically used as a source of sulfur for sulfuric acid; currently used in the manufacture of lithium batteries; widely used as an ornamental stone and in jewelry (as marcasite); highly popular for mineral collectors.

Geological facts

Commonly known as 'Fool's Gold' because its metallic luster and yellow hue often lead inexperienced prospectors to mistake it for real gold. Unlike gold, it is brittle and leaves a greenish-black streak.

Field identification & locations

Identify by its cubic crystal shape, brassy color, and high hardness (it cannot be scratched by a copper coin). Found globally with notable deposits in Spain, Peru, and the USA. Collectors look for sharp, mirror-like crystal faces.