: It commonly forms perfect cubic, octahedral, or pyritohedral (12-faced) crystals.
), is the most abundant sulfide mineral in the Earth's crust. While it earned its nickname by deceiving 19th-century gold rush prospectors, it has since been recognized as a cornerstone of human industrial and scientific progress. Chemical and Physical Properties Fools Gold
: Pyrite is much harder than gold, rating 6 to 6.5 on the Mohs scale . It is brittle and will shatter if struck, whereas gold is soft and will indent. : It commonly forms perfect cubic, octahedral, or
: When scraped against unglazed porcelain, pyrite leaves a greenish-black streak , while real gold leaves a golden-yellow streak . Chemical and Physical Properties : Pyrite is much
: Derived from the Greek word pyr ("fire"), pyrite produces sparks when struck against steel, a property used by ancient civilizations for fire-starting. Geological Formation and Occurrences
Pyrite forms in a wide variety of environments, including igneous, metamorphic, and sedimentary rocks. The Many Faces of Fool's Gold | American Scientist