THE ADIRONDACK GRAPHITE DEPOSITS 



75 



probably derived frcm the alteration of micaceous minerals. Pit no. 

 2 shows a rock with larger flake and an almost total absence of bi- 

 otite and chlorite. 



Quantitative microscopic analyses of the Hooper ores 







No. 758a 

 Pit 1 



No. 721 

 Pit 2 



No. 722 

 Pit 3 



No. 772 

 Pit 4 



No. C4-N 





Graph 

 Biotit 

 Chlor 

 Andes 

 Quart 

 Pyrite 

 Anati 

 Titan 

 Totai 





7.7 



4.7 



6.6 



13.6 



64.6 



1.2 



.9 



.7 



100.0 



4.9 



.7 



1.9 



28.1 



60.1 



2.2 



1.0 



1.1 



100.0 



5.7 

 4.9 



' 2.3 



82.2 



4.9 



"ioob 



5.0 

 1.8 

 4.8 

 23.9 

 58.8 

 5.7 



iooio 



8.7 





1.4 



it 



te 



4.5 

 8.0 



im 





75.0 



s 





.3 





te 



te. 



1.6 



fca 





100.0 



< y 









IS 



Q < 

 X 



Average 



Maximum 



Minimum 



. 5 1 mm 



X 



. 71 mm 



1 . 36 mm 



. 20 mm 



.68 mm 



X 



1. 18 mm 



1 . 35 mm 



.40 mm 



. 78 mm 



X 



1.19 mm 



2 . 05 mm 



.40 mm 



.51 mm 



X 



.91 mm 

 1 . 43 mm 



.35 mm 

















< 





J 



to 





£ 

 a. 



3 







w 



a 



H 



2 



* 2 



X u 

 H " 



H 



Average 



.44 mm 

 .85 mm 

 .20 mm 



. 78 mm 



1. 10 mm 



.35 mm 



.68 mm 



1 . 20 mm 



.30 mm 



. 74 mm 



1 . 10 mm 



.30 mm 



.90 mm 



2 . 50 mm 



Minimum 



.20 mm 



o 

 w 

 So 



55 Z 



*2 

 a u 



Z U 



x X 



Average 



Maximum 



.036 mm 

 . 050 mm 

 .021 mm 



.037 mm 

 . 080 mm 

 .020 mm 



. 038 mm 

 . 059 mm 

 .015 mm 



.046 mm 

 . 060 mm 

 .030 mm 



. 053 mm 

 . 150 mm 

 . 020 mm 









Microscopic measurements on Hooper concentrates 



GRADE 



Plus no. 8 i 

 Silk 



Minus no. 8 

 Silk 



Average diameter 



.33x .65 mm 



1 . 05 mm 



.21 mm 



. 17 x .23 mm 



Minimum diameter 



.08 mm 







i Chemical analyses by H. F. Gardner give 89.00 and 86.32 per cent graphitic carbon for these 

 two grades respectively. 



The last pit exposes the poorest grade found. It is possible that 

 the samples secured do not represent the average run, as they may 

 have been taken from near the top of the stratum. The texture 

 indicates, however, that the metagabbro, which is not far away, 

 has affected it. 



