6 PHYSIOGRAPHY. 



CLASS II. 



(Pr 4- oo) 3 (n) = 9681'; (Pr 2) 5 ; (Pr I) 3 ; 



Pr 1 (e) = 129 45'; Pr (rf) = 93 4(X; 



Pr + 1 (f) - 54 48'; Pr 4- cc (*); Pr 1 (o) 



= ST 8' ; 5 Pr = 64 44'; Pr (p) = 50 51' ; 



Pr 4- oo (r). 



Char, of Comb. Prismatic. 



Combinations. 1. P QD. Pr 1. Pr. Pr 4- QD. 

 Pr 4- oo. Fig. 24. Braunsdorf, Saxony. 



2. P (3D. Pr 1. P. (Pr+oo) 3 . pr-foD. 

 Pr -f QD. Neusohl, Hungary. 



3. P oo. Pr 1. Pr. Pr+1. Pr 1. 

 (Pr I) 5 . P. Pr. (Pr+oo)'. Pr+oo. 

 Pr 4- oo. Fig. 181. Cornwall. 



4. P oo. fr 1. Pr 1. P 1. Pr. f Pr. 

 (p r I) 5 . (Pr 2) 5 . Pr. (Pr I) 5 . P. 

 (fr-f oo) 3 . Pr-f -x. Pr-t- oo. Neudorf, Anhalt. 



Cleavage, imperfect ; the most distinct is parallel 

 to Pr + GO, less distinct cleavages are observed 

 parallel to P oo and Pr + GO ; traces of Pr 1 

 and (Pr + oo) 3 . Fracture conchoidal, uneven. 

 Surface, nearly equal in all the forms, often 

 highly smooth and splendent. The stria? paral- 

 lel to the intersections with Pr almost always de- 

 pend upon regular composition. 



Lustre metallic. Colour steel-grey, inclining to 

 blackish lead-grey or iron-black, according to the 

 physical quality of the surface. Streak un- 

 changed. 



Brittle. Hardness = 2-5 ... 3-0. Sp. Gr. = 5-763, 

 crystals from Anhalt. 



