of the P yr it e s. 45 



There is no inftance of it on lead or tin ores. And the 

 foil-fik'cr, manifeftly fprinkled on the glimmerygra- 

 nate-ore from Norway, lies rather on the Allures or 

 fibres traverfing this vein-itone than on the granate. 



The fame may be affirmed of native gold, and 

 the like attention is to be ufed in judging of the 

 gold-famples. Yet lb far does gold differ from 

 filver, that it is ufually to be met with on white 

 pyrites ; of which it may at leait -be faid, that it is 

 peculiarly fitted for the conception of gold. Again, 

 native filver is chiefly lodged with arfenical ores, 

 excepting white arfenical pyrites -, native gold in 

 cinnabar and quickfilver ores. 



In the coarfe veins, as they are called at Friberg, 

 where we chiefly look for lead and copper ores, 

 pyrites more readily lodges than in filver ores. Nay 

 in thefe lait pyrites is either entirely abfent, or 

 fo fparingly prefer::. /.: in many -places, as at 



Schenceberg, Johaa-Gcorgen Stadt, &c. the ores 

 can hardly be worked without it, (b iudifpenfably 

 necefiary an inftrument is the pyrites in the 

 i melting huts. 



The pyrites proves a fure guide to lead and 

 ropper ores, which with us are not eafily feparable, 

 feeing they generally lit: fo mixed together, or fo near 

 each other, in one. and the fame vein, that it ap- 

 pears almoft impoflible for the one to be without 

 the other : and indeed it is no eafy matter to find a 

 vein in the earth, in what direction, and to what 

 depth foever it runs, unaccompanied with pyrites. 

 And of the coarfer veins, efpecially genuine head- 

 veins, it may moreover be faid, as thofe of Hartz 

 can verify, that pyrites is often, in company with 

 :el and mocklead, to be met with, as far as 

 ievels and (hafts lave hitherto reached And tho* 

 as a pure iron-pyrites^ it often lofes itfelf, yttt it docs 

 net as a copper^ nay it often is prefent in both 



ms, intermixed with galena, and frequently 



wound 



