no Of the Iron 



gary, and other parts, do, by throwing in iron, 

 let fall the fineft fort of copper, it does not follow 

 that they are purely coppery, feeing there are few 

 pure copper-pyrites in nature : and fuch pyrites as 

 naturally turn to vitriol, cannot do fo without 

 fome admixture of iron •, but a pure copper-vitriol 

 mud be folely prepared from fine, fmelted copper ; 

 or otherwife, by art, and with the greatefb atten- 

 tion feparated from mixt vitriol. The third fort 

 is the moft common and univerfal at mines and 

 huts ; and, whether native or factitious, it will, 

 upon proper trial, particularly upon a due fepara- 

 tion, be found to be mixed. The firft fort is, 

 neverthelefs, not fo very rare, that we need go in 

 queft of it as far as Almerode in HelTe. But tho' 

 our fulphur and vitriol pyrites , as they are called, 

 generally contain fome copper, yet, by a due eva- 

 poration, and cryftallifation, of fuch vitriolic ad- 

 mixture, a confiderable quantity of pure iron vitriol 

 may be procured. 



(4.) It is alfo obfervable, that the regulus pro- 

 cured in fmelting for copper-ores, and called black 

 copper, has that black colour chiefly, if not al- 

 ways, from the iron fuch ores happen to contain : 

 moreover, there is no one fort of copper- ore, that 

 remains untouched by the magnet. 



(5.) I might here alfo alledge thofe fcoria?, 

 which, in copper- ore proofs for filver, always arife 

 dark and black ; whereas, doubtlefs, had there 

 been no iron, the colour would prove of a liver, a 

 brown-red, even to a high- red call, the proper 

 colour of copper : for though lead, without which 

 no incoclion, or fcorification, can poflibly be made, 

 mould happen to mix with it, yet it could not 

 entirely deftroy the original colour of the copper; 



as 



