The mineral pyrite, or iron pyrite, is an iron sulfide with the formula FeS2. This mineral's metallic luster and pale-to-normal, brass-yellow hue have earned it the nickname fool's gold due to its resemblance to gold. The color has also led to the nicknames brass, brazzle and brazil, primarily used to refer to pyrite found in coal.
Pyrite is the most common of the sulfide minerals. The name pyrite is derived from the Greek πυρίτης (purit¨¥s), “of fire” or "in fire”, from πύρ (pur), “fire”. In ancient Roman times, this name was applied to several types of stone that would create sparks when struck against steel; Pliny the Elder described one of them as being brassy, almost certainly a reference to what we now call pyrite.By Georgius Agricola's time, the term had become a generic term for all of the sulfide minerals.