OUDER XII. EHOMBOHEDEAL BUBY-BLENDE. 39 



3. (! p 1)3. (P)3. p + CD. Saxony. 

 4 R 2. R 1. (P) 3 . P + oo. Beschertgluck, 

 Saxony. 



5. R 1. (P 2) 3 . R. P+oo. Joachimsthal, 

 Bohemia. 



6. R + 1. (P) 3 . R + .. P 4- QD. Marienberg, 

 Saxony. 



7. R 1. R -f 1. (P) 5 . (P) 5 . P + oo. Beschert- 

 gliick. 



8. R 1. (P 2) 3 . R. (P I) 3 . (f P I) 5 . 

 (P) 5 . P +OD. Fig. 126. 



Cleavage, R, in several varieties pretty distinct, 

 in others scarcely observable. Fracture conchoi r 

 dal. Surface, R 2 streaked parallel to the 

 edges of combination with R 1 ; R 1, 

 (P 2) 3 and the pyramids belonging to R, also 

 P + oo often striated parallel to their common 

 edges of combination ; P + oo is sometimes rough, 

 as is also (| P I) 5 . 



Lustre common adamantine in light coloured va- 

 rieties, metallic adamantine in dark coloured ones. 



Colour iron-black ... cochineal-red. Streak several 

 shades of cochineal-red, corresponding to the 

 colour ; in some varieties it is almost aurora-red. 

 Semi-transparent ... opake. 



Sectile. Hardness = 2-0 ... 2-5. Sp. Gr. = 5-846, 

 crystals from Beschertgluck. 



Compound Varieties. Twin-crystals. 1. Face 

 of composition perpendicular, axis of revolution 

 parallel to an edge of R 1.. Fig, 139. This 



