62 NEW YORK STATE MUSEUM 



of outcrop of the graphitic schist (called for our purpose the Bear 

 Pond schist) follows a Z-shaped pattern on the map. 



Grenville stratigraphy. The folding and compression make it 

 difficult to be sure of the succession of the different beds. The 

 lowest member exposed; however, is limestone, which is found in 

 one place near the camp. It may be equivalent to the " sandy " 

 limestone shown on the southern edge of the Dixon and Faxon map. 

 The next formation is the sillimanite schist called the Catamount 

 schist from Catamount mountain near the International Graphite 

 Company's property west of Pottersville in Warren county. In the 

 hand specimen the long prismatic needles of the mineral sillimanite 

 are shown. 



The next rock is the Bear Pond schist — the graphitic member. 

 It is uncertain how thick this formation is, but it is about 30 feet. 

 Frequently this grades into a biotitic schist. Above the ore, 

 stratigraphically, is the amphibolite, very possibly the Beach Moun- 

 tain rock of the Faxon property. In mapping the Bear pond region 

 it was often impossible in the field to distinguish this from the 

 metagabbro and so the two rocks have been mapped together. With 

 the microscope one can frequently distinguish them. Interbedded 

 in the amphibolite are numerous lenses, lentils and drawn-out 

 masses of sandy quartzite and sillimanite schist. It is doubtful if 

 these can be ascribed to any definite place in the stratigraphic table. 



Several igneous rocks are shown here. The first one to be noted 

 is the metagabbro. Petrographic examination reveals that it was an 

 augite monzonite; now it is a hornblende-feldspar (ortho-) schist. 

 It was injected into the sedimentary strata before the isoclinal fold- 

 ing took place. Many small knobs puncture the Catamount schist, 

 frequently exhibiting contact effects on the margins. This rock is 

 much in evidence in the vicinity of Rock pond, where it has injected 

 the " arkosite " in " lit-par-lit " fashion. 



After the folding and lateral compression the area has been 

 invaded by the Algoman syenite and granite. Very often this rock 

 has absorbed, through assimilation, various members, of the Gren- 

 ville series, forming syntectic rocks. Numerous pegmatite bosses 

 cut all rocks shown on the map. On the eastern slope of the 

 mountain the Catamount schist is cut to pieces by them in such a 

 manner as to indicate that the main body of the syenite granite is 

 not far below the present surface. 



