Pyrites n. (Min.) A name given to a number of metallic minerals, sulphides of iron, copper, cobalt, nickel, and tin, of a white or yellowish color. Note: The term was originally applied to the mineral pyrite, or iron pyrites, in allusion to its giving sparks when struck with steel. Arsenical pyrites, arsenopyrite.
Auriferous pyrites. See under Auriferous. Capillary pyrites, millerite.
Common pyrites, isometric iron disulphide; pyrite.
Hair pyrites, millerite.
Iron pyrites. See Pyrite. Magnetic pyrites, pyrrhotite.
Tin pyrites, stannite.
White iron pyrites, orthorhombic iron disulphide; marcasite. This includes cockscomb pyrites (a variety of marcasite, named in allusion to its form), spear pyrites, etc.
Yellow pyrites, or Copper pyrites, the sulphide of copper and iron; chalcopyrite.
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