[1] : The Collaborative International Dictionary of English v.0.48

pyrite \pyr"ite\, n.; pl. pyrites. cf. f. pyrite. see
   pyrites. min.
   a common mineral of a pale brass-yellow color and brilliant
   metallic luster, crystallizing in the isometric system; iron
   pyrites; iron disulphide.
   1913 webster

         hence sable coal his massy couch extends,
         and stars of gold the sparkling pyrite blends. --e.
                                                  darwin.
   1913 webster
see also:
pyrites 

[2] : The Collaborative International Dictionary of English v.0.48

pyrites \pyri"tes\, n. l., fr. gr. ?, fr. ? fire. see pyre.
   min.
   a name given to a number of metallic minerals, sulphides of
   iron, copper, cobalt, nickel, and tin, of a white or
   yellowish color.
   1913 webster

   note: the term was originally applied to the mineral pyrite,
         or iron pyrites, in allusion to its giving sparks when
         struck with steel.
         1913 webster

   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.
      1913 webster pyritic
see also:
pyre arsenical pyrites auriferous pyrites auriferous capillary pyrites common pyrites 
hair pyrites iron pyrites pyrite magnetic pyrites tin pyrites 
white iron pyrites yellow pyrites copper pyrites 

[3] : WordNet (r) 2.0

pyrites
     n : any of various metallic-looking sulfides of which pyrite is
         the commonest

Pyrites >> P Words
Pyrites, definition of term: Pyrites
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