m the Pyrites: 227 



parator and dhTolver; but in decompounds, fuch a s 

 minerals moftly are, the reverfe may rather be af- 

 firmed ; for, the fire rightly enough difiblves the 

 pyrites into its parts, fo as Separately to exhibit its 

 fuJphur, arfenic, copper, and iron ; whereas the 

 air, by the act of vitriolifation, quite deftroys the 

 fulphur, not to mention the metallic portion, which 

 in this cafe is taken into the vitriol-mafs, and thus 

 becomes transformed. 



Now to apply this to our pyrites; it may juftly 

 be afked, whether the gold be parted, or formed 

 from it, and thus be either formally, or potentially 

 therein ? By fpontaneous vitriolifation a gold-yield 

 is neither to be induced, nor increafed in the py- 

 rites •, nay, though by thefe deftructions there hap- 

 pen extraordinary precipitations of fome earthy par- 

 ticles, that often partake fomewhat both of gold 

 and filver ; yet fuch conjectures are with difficulty 

 proved : for, gold-pyrita are either coppery, or 

 arfenical, or participating generally of both. Now 

 fuchdo either not fufficiently, or not at aii vitrio- 

 1 ife-,and foffile or native ochres, or pyrites-earths , 

 feveral times allayed for gold, I found to have little 

 or no yield. 



Suppofe now we have recourfe to the fire, and 

 then the pyrites either is, or is not roafted ; in the 

 latter cafe, it is taken crude, dofed with lead, and 

 fcorified, and the lead-regulus driven, or copelled, 

 that is, the noble is driven or parted from the ig- 

 noble metal. Now here we procure a filver-grain^ 

 at lead from the lead, were there no fiber at all in 

 the pyrites itfclf \ in this grain the gold mult lodge : 

 this filver -grain is committed to depart- waters, 

 namely, the gold parted from the filver, and ig- 

 nited, which finifhes the procefs. Now though 



Q^2 this 



