682 



DEPARTMENT OF THE INTERIOR 



GROUP III. 



2 GEORGE V. f A. 1912 





Plutonic. 



Effdsive. 



Plutonic. 



Effusive. 





17 



18 



19 



20 





Laurvikite 

 (Osann). 



Rhomb-porphyry 

 (Washington). 



Monzonite 



(Osann and 



Washington). 



Latite (Ransome 

 and Daly). 



No. of Analyses. 



3 



57 '45 



21 11 



2-89 

 239 



1 Ob 

 4-10 

 5-89 

 3-87 

 •70 

 ■54 



7 



57 45 



19-53 

 } 6-47 { 



i : 28 

 311 

 635 

 446 

 135 



12 



55 25 



•60 



16 53 



303 



437 



15 



420 



719 



3-48 



4 11 



•66 



■43 



10 



Si0 2 



Ti0 2 



AI2O3 



57 



1 



16 



2 

 4 



3 

 5 

 3 

 4 



65 

 00 

 68 



Fe 2 3 



29 



FeO 



MnO 



07 

 10 



MgO 



CaO 



NasO 



K 2 



H 2 



P 2 6 



22 



74 1 



59 



39 



91 2 



36 



Calculated as Water-free. 



Si0 2 . 



Ti0 2 . 



AI2O3 



Fe 2 3 



FeO. 



MnO. 



MgO. 



CaO. 



Na 2 



K2O. 



P2O5. 



57 



85 



21 



26 



2 



91 



2 



41 



1 



07 



4 



13 



5 



93 



3 



90 





54 



58-24 



i9 : 79 

 656 



i : 30 

 3- 15 

 644 



452 



55 



62 



58" 





60 



1 



16 



64 



16- 



3 



05 



2- 



4 



40 

 15 



4- 



4 



23 



3" 



7 



24 



5' 



3 



50 



3 



4 



14 



4- 



•43 





S-18 

 .01 

 i-84 

 !31 

 111 



10 

 {•25 

 i'79 1 

 t 62 

 I 43 



•36 



Each sura = 10000. » Includes . 16% BaO and .07% SrO. 2 Includbs .14% COj. 



