rm-: sa rru.ii.isi . t>m. 



1^1. ATK X. 



Fig I. Cordierite>Mica=schist, 5inen Gill; x 25, natural light. 



Tlu clciU' spaces represent irregular crystal-grains of cordierite. The other constilmiits 

 arc hiotite. niuscovite, quartz, andalusite. and graphite. 





I'i.if. 2. Cordierite-Mica-schist, liurdell (iill, Caldew Valley; x 25, 

 crossed nicols. 



Showing a cross-section nf a ciniplcx twin of cordierite. 



