Spear and cockscomb ones are known as "white" or marcosite, and it is mined commercially as a source of sulfur.
The eye sockets of Aztec skull masks were fill with it, and it was also used in a wheel-lock gun in the "dog." Weathering of it results in the formation of goethite or limonite, and . If it is nickel-rich, it is referred to as bravoite, while magnetic minerals of it are called pyrrhotite. Spear and cockscomb ones are known as "white" or marcosite, and it is mined commercially as a source of sulfur. FTP, identify this mineral with chemical formula FeS2 that is better known as fool's gold.
The eye sockets of Aztec skull masks were fill with it, and it was also used in a wheel-lock gun in the "dog."
iron {pyrite} (prompt on fool's gold)