GEOLOGY OF THE LONG LAKE QUADRANGLE 



517 



Though slightly more acid than the previous rock it has a much 

 larger percentage of femic and alferric minerals. It is also note- 

 worthy in the number of different minerals shown in the slide, 14 

 being present. The magnetite would yield 2.98% of Fe 2 3 , and 

 this is substituted for the small amount which the chemical analysis 

 yielded. 



Norm of hornblendic pyroxene-harzose (analysis 4) 





Chem. 

 comp. 



Mol. 

 ratio 



Or. 



Ab. 



An. 



Hy. 



Di. 



Mt.. 



Ti. 



Qz. 



Si0 2 



A1 2 0* 



61 .01 



I5-36 



2.98 



7-77 



.78 



4-05 



3.68 



3-9° 

 0.49 

 0.08 



1 .017 . 248 



•356 

 •059 



. 100 



.050 



.087 



■ 043 





.001 



.181 



Fe 2 3 .... 



.019 

 .108 

 .019 

 .072 

 .0^0 









.019 

 .019 







FeO .... 









.072 

 .015 



.017 

 .004 

 .021 







MgO . 













CaO 







.050 



OOI 





Na 2 . 





•059 









K 2 

















H 2 '. .. .... 





















MnO 



.001 











. OOI 





















Total 



100 . 10 





. O4I - O^Oi . CKO 



. 087 .OA1 . OIQ . OOI 



t8t 











" 













Or., 

 Ab. 

 An. 

 Qz. 



Mt. 



%l 



Ti. 



Total 99.64 



78.90 



20.74 



Class, 



SaL_ 

 Fem. 



78.90 



20.74 



^ a Q IO - 86 



Order, ■% = — =0.16 



F 68.04 



3.81 = ii, dosalane 



Rang, 



K 2 0' + Na 2 0' 



Subrang, 



CaO' 

 K 2 0" 



Na 2 0' 



4£ 

 59 



= 4, austrare 



= 1.4 = 3, tonalase 



= 3, harzose 



The rock is close to the division line between orders 4 and 5, so 

 that it is a harzose very close to shoshonose. 



The slides of the type syenite from Loon lake, analysis 5, have 

 been mislaid and could not be found, so that the readjustment of 

 the iron percentages had to be based wholly on separation of magne- 

 tite from a weighed amount of crushed rock by heavy solutions and 

 magnet. The result gave 1.58% of magnetite, or 1.09% of Fe 2 3 , 

 which is certainly much more nearly correct than the .42% of the 

 original analysis. Its norm would thus become: 



