mineral

Pyrite

Iron Disulfide (FeS2)

Hardness: 6-6.5 on Mohs scale; Color: Pale brass-yellow; Luster: Metallic; Crystal Structure: Isometric (often cubic or pyritohedral); Cleavage: Indistinct; Specific Gravity: 4.8-5.0

Hardness: 6-6
Color: Pale brass-yellow
Luster: Metallic

Identified July 21, 2026More mineral →

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Physical properties

Hardness: 6-6.5 on Mohs scale; Color: Pale brass-yellow; Luster: Metallic; Crystal Structure: Isometric (often cubic or pyritohedral); Cleavage: Indistinct; Specific Gravity: 4.8-5.0

Formation & geological history

Forms in diverse environments including hydrothermal veins, as a magmatic segregation mineral, in sedimentary rocks (shale, coal, limestone) via precipitation, and in metamorphic rocks.

Uses & applications

Primarily used as a source of sulfur and sulfuric acid in industrial chemicals; occasionally used as an ornamental stone or in costume jewelry (often incorrectly called 'marcasite').

Geological facts

Commonly known as 'Fool's Gold' due to its resemblance to precious metal. Historically used to create sparks for wheel-lock firearms and as a semiconductor in early radio receivers.

Field identification & locations

Identify by its hardness (scratches glass, unlike gold) and its brittle nature; it leaves a greenish-black streak when rubbed on unglazed porcelain. Found globally in diverse geological settings.