QUARTZ-BEARING HYPERSTHENE-ANDESINE SYENITE 211 



Analyses of Syenite (Andesine Anorthosite) , Nelson County, Virginia 26 



I II 



Si0 2 60.44 57.06 



A1 2 3 23.02 14.54 



Fe 2 3 29 1.49 



FeO 19 4.52 



MgO 21 4.10 



OaO 5.59 4.37 



Na a O 4.94 3.13 



K s O 3.37 1.96 



H 2 0— 08 .09 



H 2 0+ 32 1.32 



Ti0 2 1.11 7.10 



P 2 5 15 .24 



MnO trace . 04 



C0 2 trace . 09 



S trace trace 



100.31 100.05 



L Average of four analyses of feldspathic facies of syenite (potash-bearing 

 andesine anorthosite) , Nelson County, Virginia. William M. Thornton, 

 Jr., analyst. T. L. Watson : Bulletin 580-O, United States Geological 

 Survey, 1914, page 399 ; for individual analyses see Watson and Taber : 

 Bulletin III-A, Virginia Geological Survey, 1913, page 78. 

 [I. Average of three analyses of hornblendic facies of syenite, Nelson County, 

 Virginia. William M. Thornton, Jr., analyst. T. L. Watson: Bulletin 

 580-O, United States Geological Survey, 1914, page 399; for individual 

 analyses see Watson and Taber : Bulletin III-A, Virginia Geological 

 Survey, 1913, page 78. 



Norms of Syenite corresponding to Analyses above 



I II 



Q 5.70 16.56 



Or 20.02 11.68 



Ab 41.40 26.20 



An 28.36 19.74 



C 82 



Hy 10.20 



II 46 8.21 



Hm 32 



Mt 2.09 



Ru .88 2.40 



Tn .98 



Ap .31 .31 



25 For analyses and complete description of this rock see Bull. III-A, Virginia Geol 

 Survey, 1913, by Watson and Taber. 



