The
mineral pyrite, or
iron pyrite, also known as
fool's gold, is an
iron sulfide with the
chemical formula FeS2. This mineral's metallic
luster and pale brass-yellow hue give it a superficial resemblance to
gold, hence the well-known nickname of
fool's gold. The color has also led to the nicknames
brass,
brazzle, and
Brazil, primarily used to refer to pyrite found in
coal.