THE ADIRONDACK GRAPHITE DEPOSITS 



77 



a portion of the same mass exposed on the Hooper property. This 

 is today a hornblende diorite. 



The ore. The ore is a quartz-feldspar schist, very likely the 

 Dixon schist, but a little lower in quartz than is the usual run. The 

 feldspar is almost entirely weathered to secondary sericite but 

 enough remains to demonstrate that it is largely andesine. The 

 graphite flake is rather small and much involved with considerable 

 chlorite and a little pyrite and biotite, reminding us of the Bly 

 ores. The graphite flake varies " from .015 millimeter to .025 

 millimeter in thickness and up to 1.3 millimeters in length; the 

 average length does not exceed 0.75 millimeter." 1 There is a lack 

 of parallelism of the flaky minerals, due to the shearing movements 

 associated with the fauking. The graphite is said to constitute 

 from 4 to 7 per cent of the rock. 



Quantitative microscopic analysis of the Champlain ore 



No. 720 

 South side of pit 



z 



Graphite 



Biotite 



5.3 



9.2 



3 7 



38.2 



38.0 



4.3 



1.3 



100.0 



u 



H 



5 



Eh 

 < 



O w 



Id 



S a 



35 < 

 H J 



O 



55 









Maximum diameter 









1 . 00 mm 









1.39 mm 



sS 





.28 mm 



R " 









U S 



Apatite 



Average length 



Maximum length 



Minimum length 





£* 



Total 



1 . 42 mm 



3£ 





.34 mm 



X 







a 







X 



< 



Minimum thickness 



.025 mm 



The pyrite is of two generations, the early introduced type has 

 irregular outlines becoming distinctly fuzzy at times. The later 

 form is in perfectly bounded cubes. Both the graphite schist and 

 the metagabbro are seamed with veins often 2 inches wide, consisting 

 of coarsely crystalline calcite, feldspar, quartz and some garnet. 

 The general strike of the beds is N io° E. 



The mill. A well-constructed mill which was built in 1905 stands 

 close to the water's edge, 300 feet from the quarry with which it is 

 connected by a short tramway. " The equipment includes a jaw 

 crusher, 12-inch rolls, broken-screw agitators, three buddies, drying 

 floor, bolting machines, tube mill, etc." 2 



Economic future. The predicament in which the Champlain 

 Graphite Company found itself is a striking example of the dis- 

 astrous results that follow the attempt to open a mine before con- 



1 Bastin, E. S., Mineral Resources, U. S. G. S. 

 2 Bastin, E. S., loc. cit. p. 823. 



909, 2:823. 



