GEOLOGY OF THE LONG LAKE QUADRANGLE 



517 



Though sHghtly 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^Oa, 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. 



SiOz 



61 .01 



15-36 

 2.98 



7-77 

 .78 

 4.05 

 3.68 

 3-90 

 0.49 

 0.08 



I .017 



•151 

 .019 

 .108 

 .oig 

 .072 



•059 

 .041 



.248 

 .041 



•356 

 •059 



. 100 

 .050 



.087 



■043 





.001 



181 



AI2O3 





Fe^Oa 







.019 

 .019 







FeO 









.072 

 .015 



.017 

 .004 

 .021 







MgO 













CaO 







.050 







Na,0 



.041 



■059 









K,0 















H2O 

















MnO 



.001 











GDI 

























Total 



100 . ID 





. 04.I ' cn 



.050 



.087 





181 



















Or.. 

 Ab. 

 An. 

 Qz.. 



Mt. 

 Hy. 

 Di.. 

 Ti.. 



23 .02 



31-13 

 13.89 

 10.86J 



4.32 

 11.03 



5-22 I 

 O.17J 



78.90 



20.74 



Class, ^""^-^ = 78^ = 

 Fem. 20.74 



Order, 8=^° -^6 



3.81 = II, dosal 



ane 



,„ =0.16^4, austrare 

 J. 68.04 



K2O' +"Na20' 100 



- — =-1.4=3, tonalase 

 72 '^ ■^' 



.7^3, harzose 



Rang, ^-^ 



C ^. K2O' 



Subrang 



" Na20 



4£ 

 59 



Total 99.64 



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

 that it is a harzose very close to shoshonose. 



The sHdes 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 Fe203, 

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

 original analysis. Its norm would thus become: 



