174 PHYSIOGRAPHY. 



Dolomite Dyoxylite. 



Hardness = 4-50 . . . 4-75. (scale of BREITHAUPT.) 

 Sp. gr. = 2-809, reddish-white, cleavage crystal. 

 2-810, brownish red, cleavage crystal. 

 2-827, dark brownish red and brown, with delicate^ 



black stripes ; both from Freiberg, 

 1. It consists, according to KARSTEN, of 



Carbonate of lime - 96-40 



Carbonate of protoxide of manganese 2-10 



Carbonate of iron - 0-95 



Water and loss 0-55 



It is found only at two mines in Freiberg. 



iv. Isometric Carbon-Spar, BREITHAUPT, 

 PonP = 106 19 ; . 

 Cleavage parallel with P perfect. 

 Hardness = 5-50 . . . 5-75. (scale of BREITHAUPT.) 

 Sp. gr =a 2-847, minute, ash-grey crystals in gypsum, from Hall. 



in Tyrol. 



2-849, greenish white masses of a compound variety, 

 from Koloseruck in Bilin, (Bohemia,) where 

 it occurs in seams in basalt. 



^ 853, minute, but possibly not perfectly pure cleav- 

 age crystals, of the above variety, from HalK 

 2-857, minute, pure, and white cleavage crystals, 



from Dinz. 



2-859, asparagus green, cleavage crystals, from 

 Schweinsdoif. (Tharaudite.) 



The variety from Hall afforded, to KLAPROTH, 



Carbonate oflime .... gg-0 



Carbonate of magnesia .... 25*5 



Carbonate of protoxide of iron - TO 



Water .... 2-0 



Foreign matter .... 2-0 



DYOXYLITE. Prismatoidal Lead-Baryte.' 

 HAIDINGER. 



Primary form. Right rhombic prism. M and M'*= 

 120 45'. 



