3 76 Elements of Mineralogy. 



SPECIES X, 



Red Calx of Iron, mixed with a fmall Propar* 

 tion of the bro<wn> and indurated. 



Torften. 



15. This is of a bright bluifh black, or 

 yellowifh grey colour, and fibrous texture, 

 {hews a red trace when fcratched, and is 

 ^yeakly magnetic before calcination. Ac- 

 cording to Mr. Rinman it is lefs dephlo- 

 gifticated than hematites. Hiftoria Ferri. 

 . 285. 



SPECIES XL 



Emery. 



16. Emery feems to be a mixture of the 

 red and white calces of iron, with fome un- 

 known liony fubftance, perhaps tripoli ; it 

 fcarcely yields in hardnefs to any fubftance, 

 except diamond; the beft fort is of a dark 

 grey colour, but becomes brown, and in 

 great meafure magnetic by calcination ; other 

 forts are of a reddifh rufty white, or yellowifh 

 colour; its fpecific gravity is from 3,000 to 

 4.,ooo ; it is never ufed as an iron ore, nor 

 is its proportion of iron well known. 



