Pyrite

Physical Properties

Hardness: 6-6.5 (Mohs scale), Color: Brass-yellow, Luster: Metallic, Crystal structure: Isometric (cubic), Cleavage: Indistinct, Specific gravity: 4.9-5.2.

Formation & Geological History

Forms in a wide variety of environments, including magmatic segregation, hydrothermal veins, and sedimentary deposits under anaerobic conditions. It is found in rocks of all geological ages.

Uses & Applications

Used in the production of sulfur dioxide for sulfuric acid, in lithium batteries (as a cathode material), and as a popular ornamental and collector stone. Historically used to create sparks for firearms.

Geological Facts

Commonly known as 'Fool's Gold' due to its resemblance to real gold. Unlike gold, it is brittle, harder than a knife blade, and leaves a greenish-black streak on a porcelain plate.

Field Identification & Locations

Identify by its cubic crystal habit, brassy color, and distinct sulfur smell when struck. Found globally in locations like Spain, Italy, Peru, and the USA. Collectors look for well-defined cubic or dodecahedron faces.

Identified on: 4/27/2026

Mode: Standard