Pyrite

Hardness of 6-6.5 on Mohs scale, pale brass-yellow color, metallic luster, isometric crystal system with cubic forms, specific gravity of 5.0.

Forms in a wide variety of geological environments ranging from igneous rocks to sedimentary formations like shales and coal beds, often precipitated from hydrothermal solutions.

Historically used to strike fire, currently used in the manufacture of sulfur and sulfuric acid, and popular among mineral collectors.

Widely known as 'Fool's Gold' due to its superficial resemblance to actual gold, though pyrite is much harder and leaves a greenish-black streak.

Easily identified by its brassy metallic color, cubic crystal habits, and high specific gravity; found globally with notable deposits in Peru, Spain, and the United States.