Plate 9 



A. Grenville gneiss, northeast of Owls Head. The clear, 

 light or gray mineral is quartz. The dark mineral is 

 chiefly diopside. Crossed nicols, actual field o.i inch or 

 2.5 mm. 



B. Inclusion of Grenville gneiss in anorthosite, just 

 south of Owls Head. The clear or pale gray minerals are 

 orthoclase or plagioclase. The darker well-cleaved min- 

 eral of high relief is diopside. Crossed nicols, actual field 

 o.i inch or 2.5 mm. 



