152 



AUSTRALASIAN ANTARCTIC EXPEDITION. 



pleochroic spots associated with granular garnet and biotite ; and sometimes the small 

 crystals of corundum appear as in the related example. Ilmenite, pyrite, and epidote 

 have been noted. The rock may be called, like No. 777, a garnet felspar gneiss. 



Chemical Characters. 



Analyses have been made of the garnet cordierite gneiss from Cape Gray and of 

 the cyanite biotite gneiss from Garnet Point. The analyst is A. G. Hall, Victorian 

 Geological Survey Laboratory. 



I. II. 



Si0 2 60-93 55-39 



A1 2 3 18-09 18-36 



Fe 2 3 1-88 .... 1-76 



FeO 5-55 6-81 



MgO 4-54 4-74 



CaO 0-90 .... 2-79 



Na 2 1-78 .... 3-36 



K 2 3-89 .... 3-74 



H 2 + 1-15 1-46 



H 2 - 0-14 0-13 



Ti0 2 1-07 .... 0-86 



P 2 5 tr 0-14 



SO S nil .... nil 



Cl tr tr. 



MnO 0-14 0-24 



NiO, CoO 0-02 .... 0-03 



CoO tr tr. 



LizO strong tr tr. 



S. 



Total 100-08 



Sp. Gr 2-752 



Group Values. 



I. 

 II. 



68-2 

 62-5 



A. 



4-6 

 6-2 



C. 



1-1 

 3-3 



14-3 

 15-9 



M. 



T. 



6-0 

 2-6 



99-81 



2-804 



K. 



1-5 

 1-0 



Projection Values. 



a. 



4-6 

 4-9 



c. 



1-1 

 2-6 



14-3 

 12-5 



I. Specimen No. 781-Garnet Cordierite Gneiss, Cape Gray, Adelie Land 

 II. Specimen No. 772-Cyanite Biotite Gneiss, Garnet Point, Adelie Land. 



