Cobalt. 339 



1 779. p. 1 6. So alfo the PruJJlan alkali will firft 

 precipitate the iron blue, and afterwards the 

 cobalt reddifh, (ibid.) or rather grey. 



SPECIES V. 



Mineralized by Sulphur and Arfemc 'with Iron. 

 White arfenicated Cobalt Ore, Kobalt Glantz. 



10. This bears a great refemblance to the 

 Jaft, but is fofter, for it never ftrikes fire with 

 fteel, and fometimes it is fo foft that it may be 

 fcraped with a knife ; it rnoftly appears under 

 fome polygon form > the moft ftiining forts 

 of this, and of the former Species, have been 

 called Cobalt Glantz. 



It is analyfable like the former Species ; the 

 fulphur may be caught on the filter. 



SPECIES VI. 



Mineralized by a fmall Proportion of Sulphur 9 

 with a notable Proportion of Iron without 

 any Arfemc. 



White unarfenicated Cobalt Ore. 



11. It is fometimes found in large mafles, 

 and fometimes in grains cryftalized, of a dull 

 \yhite colour, and frequeutly bears the ap- 



Z 2 pearance 



