HORNBLENDE SCHIST. 313 



The only minerals hitherto found embedded 

 in hornblende schist are iolite, pyrites^ and gar- 

 net. The latter sometimes occurs in such quan- 

 tity as materially to modify the appearance of the 

 rock. It is sometimes imperfectly crystallized ; 

 or more perfectly, as it is in micaceous schist : in 

 some rare cases, it is disposed in laminae among 

 those of the hornblende, 



