IIG 



FOYE. 



rock consisting of feldspar and augite. The laths of feldspar are 3 

 to 4 mm. long and 1 to 2 mm. wide and between them in diabasic 

 arrangement is a felted mass of fibrous augite and hornblende. The 

 rock breaks irregularly and is but slightly altered. 



The weight proportions of the essential minerals are: — 



Augite and uralitic hornblende 14.3 



Feldspar 84.8 



Iron ore .9 



100.0 



The larger part of the feldspar is a meflium labradorite, (Ab4oAn6o). 

 Zoned feldspars show the following composition, passing from the 

 inner to the outer zones: — 



Anorthite AboAngs 



Basic labradorite AbisAnys 



Medium labradorite Ab4oAn6o 



Andesine AbesAuss 



The augite is in irregular, shattered bits, some of which are included 

 in the outer zones of the feldspars. 



The gabbro has the following chemical composition: — 



SiOo 50.01 



TiOz 1.01 



AI2O3 19.33 



FeoOs 1.85 



Feb (3.26 



MnO 21 



MgO 3.51 



CaO 12.38 



NasO 2.13 



K2O 0.18 



P2O5 trace 



H.,0+ 1.85 



H.,0 — 1.55 



Total 100.27 



Specific Gravity at 20°C = 2.753 

 Analyst — P. C. Voter, 



Norm 



Quartz 5 . 40 



Orthoclase 1.11 



Albite 17.82 



Anorthite 42 . 53 



Diopside 15.62 



Hypersthene 9 . 78 



Magnetite 2 . 78 



Ilmenite 1.98 



Water 3.40 



Total 100.42 



