THE ADIRONDACK GRAPHITE DEPOSITS 95 



present; one is brown biotite (perhaps the variety known as 

 haughtonite), while the other is a pale yellow-green mica approach- 

 ing chloritic or chloritoid forms. (The latter may be ottrelite in 

 part.) Pvrite is present but a little lower in amount than is usually 

 the case. The richness of the ore and its high potash (microcline) 

 content point to igneous activity similar to that displayed at the 



ALGOMAN 

 GRANITE. 



M t l ll ll ll 

 M illi n g 



LAURENTIAN 

 GRANITE 



mm 



0UARTZ1TE 

 (SWEDE PD.') 



^B 



LIMESTONE 

 ( 'FAXON' 1 



QUARTZ 

 SCHIST. 



GRAPHITE 

 SCHIST 



CNEISS 

 ("HAGUE") 



AMPHIBOLITE 

 ('DRESDEN ) 



LIMESTONE 

 (JOHNSBURG"' 



QUART2ITE 

 CSACANDAGA") 



Fig. 21 Generalized block diagram of the Sacandaga Graphite Com- 

 pany's property, showing the inclined pitching syncline, invaded by both 

 the Laurentian and the Algoman granites. The three pits are indi- 

 cated near the apex of the fold. Length of the block is about one- 

 fourth of a mile. Structure by G. H. Chadwick. Geology by H. L. 

 Ailing, 1917. 



International and Rowland mines. The graphite appears to have 

 been reorganized and redistributed, developing a very rich zone. 

 The graphite flakes are not confined to the schist, as the adjacent 

 rocks contain scattering amounts. 



