:;i6 



NEW YORK STATE MUSEUM 



Chemical composition and norm of hornblendic 



augite- 



iaurvikose 





Chem. 

 comp. 



Mol. 

 ratio 



Or. 



Ab. 



An. 



Co. 



Hy. 



Mt. 



Qz. 



Si02 



AI2O5.... 

 Fe203.... 



FeO 



MgO 



CaO 



Na20.. .. 



K2O 



H2O 



MnO 



59-7° 

 19-52 

 1.89 

 4.92 

 .78 

 3-36 

 5-3^ 

 4 -14 

 0.52 



■995I -263 



•514 

 .086 



.123 

 .o6t 



.0004 



.076 





.019 



.0X2 

 .068 

 .019 

 .060 

 .086 

 .044 



• -t't 





.012 

 .012 













■057 

 .019 



















.060 









• 044 



.086 







































.001 

























Total . . 



1 

 100.23: 



■ 044 



.086 



.061 





.076 



.012 .019 



Or 24.40] 



Ab. . .. 44.85 „ 



An 17.04 ^7.49 



Co o .04 I 



Oz 1.16J 



Class, ^^ = ^7.49 

 Fern. 



7.21 = I, persalane 



Order, § 

 F 



12.13 

 ^ ■ ^ =.013 = 5, canadare 



Mt. , . . 2.73 

 Hy . ... 9.40 



Rang, 



'b-33 

 K20' + Na.O' 



12.13 



--^ = 2.1 = 2, pulaskase 

 613 



CaO' 



Subrane - — - = '^'^ = .51 = 4, Iaurvikose 

 Bunrang, ^^__q, g^ i 4. 



Total 99.62 



The rock is close to the border between classes I and II, and 

 also between subrangs 3 and 4, so that it is near both pulaskose 

 and akerose, more especially the latter. 



The rock of analysis 4 has the following mode 



Units 

 Units measured Sp. Gr. by weight 



Microperthite 1546x2.6 = 401 1 



Plagioclase 159^2.63 = 417 



Quartz 247x2.65 = 654 



Augite 143x3.3 = 472 



Bronzite 63 x 3 . 3 = 208 



Hornblende 127x3.2 = 406 



Garnet 84x3.7 = 311 



Magnetite 57x5.25 = 299 



Apatite 22x3.2 = 70 



Titanite 6x3.5 = 21 



Pyrite 6x5.0 = 30 



Zircon : • • 2x4.5 = 9 



% weight 



J 8. 07 



6.04 



9-47 

 6.83 

 3.01 

 6 .01 

 4-50 

 4-33 

 1 .01 



0.33 

 0.43 

 0.13 



Total. 



A'. 



2462 



6908 



100 . 16 



Also biotite and allanite i each. 



