mineral

Pyrite (fool’s gold)

Pyrite, iron disulfide (FeS₂)

AI-generated identification · may be incorrect

Brassy metallic luster with granular, glittering crystals; typically pale brass-yellow and opaque. Mohs hardness 6–6.5; isometric crystal system, specific gravity about 5; cleavage is poor or indistinct.

Identified September 25, 2026More mineral →

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Physical properties

Formation & geological history

Forms in sedimentary rocks, hydrothermal veins, and metamorphic settings, often where iron and sulfur react under low-oxygen conditions. Pyrite occurs across geological ages, from ancient deposits to modern sediments.

Uses & applications

Used historically as an iron and sulfur source and occasionally in jewelry, décor, and mineral collections; it is generally not a major iron ore because of sulfur-related processing issues.

Geological facts

Its metallic yellow color can resemble gold, but pyrite is harder and more brittle. Weathering can produce acidic drainage and iron-sulfate minerals.

Field identification & locations

Look for a brassy color, metallic sparkle, and brittle fracture; crystals are often cubic, though this specimen appears granular. Common worldwide, including Spain, Peru, Italy, and the United States.