5/"^Pyrites. 19 



iecretary, Mr. Lichtwer, a perfon extremely well 

 (killed in the bufinefs of minerals, fhewed me 

 fometime ago at Drefden a fteely-clofe pyrites-die 

 from Norway, from which there ifTued a pretty 

 large thread of native filver : But this filver we 

 mull not confider as growing out of the body of 

 the pyrites, but as fomething exifling previous to, 

 and encompafTed by the pyrites, and which probably 

 might have had its root or origin in a quartz 

 or /pad, as fuch a body actually adhered to it, 

 and in fuch, native filver often lodges ; having 

 myfelf had from Norway a quartzy or flinty fample, 

 clofely intermixed with foils of filver, under the 

 title of a filver -pyrites, tho' nothing of a pyrites was 

 obfervable thereon. 



From the other contents of the pyrites have 

 arifen the appellations of fulphur, vitriol, arfenic 

 and fandarach pyrites, and accordingly pyrites have 

 in fome meafure been forted ; in particular, ful- 

 phur and vitriol pyrites is a diftinction with- 

 out a foundation -, feeing all pyrit<e, containing 

 fulphur, yield vitriol too •, and all yielding vitriol, 

 muft needs have held fulphur : but it is proper to 

 obferve, that they muft be firft worked for their 

 fulphur, then for their vitriol •, and that pyrites 

 once worked for vitriol, irretrievably lofes its ful- 

 phur. So that this divifion of pyrites has only 

 ferved to introduce error and mifconception into 

 the fubjecl •, as if thefe were quite diftinct fpecies 

 of pyrites, and that fome pyrites held vitriol for- 

 mally, and in their native compofition, in manner 

 as moft of them do fulphur. Tho' this is not to 

 be taken ftrictly neither, as there are fome at- 

 tending circumftances to juftify fuch a divifion, 

 for the fake of illuftration, tho' not of neceflity : for 

 inflance, at Geyer in Meifnia there are chiefly two 

 forts of pyrites -, the one of Catherin-mine at Johan- 

 Georgen-Stadt - 7 the other, of the pyrites groove of 

 C 2 Geyer 



