452 CHARACTERISTIC. CLASS IT. 



1. HEXAHEDRAL. Tessular. 



Cleavage, hexahedron, perfect. 



Prismatic Manganese-Blende. J. iii. 3 1 . 



II. GARNET-BLENDE. Tessular. 



Streak uncoloured ... reddish-brown. 

 H. = 35 ... 4-0. 

 G. 4-0 ... 4-2. 



1. DODECAHEDRAL. Semi-tessular with inclined faces. 

 Cleavage, dodecahedron, highly perfect. 



Dodecahedral Zinc-Blende. J. iii. 32. 



III. PURPLE-BLENDE. Prismatic. 



Streak cherry-red. 

 H. =r 1-0 ... 1-5. 

 G. =4-5 ... 4-6. 



1. PRISMATIC. Hemi-prismatic. 

 Cleavage prismatoidal. 



Red Antimony. J. iii. 36. 



IV. RUBY-BLENDE. Rhombohedral, prismatic. 



Streak red. 



H. = 2-0 ... 2-5. 



G. = 5-2 ... 8-2. 



1. RHOMBOHEDRAL. Rhombohedral. R = 108 18'. 

 Combinations sometimes different on the opposite ends 



of the crystals. 

 Cleavage, R. 

 Streak, cochineal-red. 

 H. = 2-5. 

 G. = 5-4 ... 5-9. 



Rhomboidal Ruty-Bknde or Red Silver. J. iii. 38. 



