134 



TRANSACTIONS OF THE 



FIFTH ORDER— BLENDE. 



Semi-metallic and common lustre, colored streak. 

 H. from 1 to 5f. 



G. from 3, 2 to 8, 1. 



Semi-metaliic lustre ; green or red streak. Ex- 

 amples — miargyrite, or rather meiargyrite, 

 because it contains less silver than the common 

 red silver ore. 



Common lustre; yellow, red or brown 

 streak, or if uncolored, with dodecahe- 

 dral cleavage. 

 H. from 1 to 3§ ; color and streak red or yellow. 



Examples — red antimony and cinnabar. 

 H. from 3| to 4§, red streak, and G. more than 

 5 ; as red silver ore, or dodecahedral cleav- 

 age, as dodecahedral Zinc blende, Jam. 

 H. from 4| to 5|. 

 G. from 3, 8 to 4, 1. 

 Tesseral ? semi-metallic lustre and green streak, 

 as in manganese blende, or common lustre. 



SIXTH ORDER— KERATE. 



Diamond lustre. Without perfect cleavage in one di- 

 rection only. 



H. from \ to 2, from malleable to sectile. 

 G. from 5, 4 to 7, 7. 



Examples — chloride of silver or mercury ; iodide 

 of silver, Vauq. 



