in the Pyrites. 269 



tatiors of nam re, entirely depend. With fulphur- 

 ,es it in ibme meafure fucceeds; as the flag, 

 ich fometimes fettles on the lead, depofited out 

 of lead-ore by means of iron, and which certainly 

 confiits of iron and fulphur., is to be regarded as a 

 kind of pyritcf. 



[4^ The arfenic in the white-pyrites is not fufE- 

 ciently faturated with iron- earth, but can dill bear 

 with facility almoft as much again, as it had 

 already received ; as may be (hewn by its regula- 

 tion, which is performed with iron. We have 

 pure, clean fulphur, alio pure clean arfenic in the 

 bowels of the earth ; and thus they may not only 

 confift, but be alio produced without iron. 



(5.) The white-pyrites contains alfo a little fii- 

 ver -, in this entirely agreeing with the fulphur pyrites. 

 But when arfenic is combined with an earth, yield- 

 ing imalt, and then called cdbald, it becomes remark- 

 ably more filvery, yet in variable degrees : this we 

 alfo obfcrve of fulphur -pyrites, when its iron- 

 earth is coppery. And the comparing together 

 of the white and yellow pyrites in general, with re- 

 flect to their earths •, at one time yielding fmalt, at 

 another copper, and the exaltation of their filver- 

 yield hence vifibiy depending, would be worth our 

 peculiar attention And he who would verify his 

 fufpicions about noble miff-pi eke Is, mould accu- 

 rately examine the famplehe is about to employ for 

 proof, in order not to be deceived by other unob- 

 ier?ed, interfperfed veins therein. 



{6.) The pyrites gold is not very common. A3 

 I would not be impofed upon by the white, as little 

 would I by the yellow colour of the fulphur- pyrites, 

 I am well aware or the difference between white and 



P yellow 



