﻿Pig. 7. — -Crystal of chalcopyriie (with scratched surface), enveloped 

 by blende (dark) and galena (white) : Nenihead Mine, 

 Allendale. (Reflected light : X 200.) 



Fig. 8. — Crystal of chalcopyriie enveloped by galena : 

 Leadhills Mine, Lanarkshire. (Reflected light : x 200.) 



