44 NEW YORK STATE MUSEUM 



These are usually separated by the same kind of rock that forms 

 the footwall, which is garnetiferous gneiss. The American Graphite 

 Company in its main mine is probably following the lower bed, 

 there the thicker of the two. As the rock that forms the roof is the 

 same as the footwall, it has been assumed that the rock that over- 

 lies the ore is garnetiferous gneiss. The writer would emphasize 

 this fact, for some confusion has resulted from incorrect statements. 1 



The upper bed of the Dixon schist is usually capped by a lime- 

 stone, although this is occasionally absent. The limestone is some- 

 times pure but more frequently siliceous. This formation the writer 

 chooses to call the Faxon limestone, taking the name from Faxon 

 pond. No definite statement can be made as to the thickness, as it 

 has been molded and stretched like so much putty under the stresses 

 to which the whole region has been subjected, but a maximum 

 thickness of 20 feet can be given. 



The Faxon limestone is capped by a quartzite, 2 usually vitreous, 

 approaching a glassy phase in certain localities. This is referred 

 to as the Swede Pond quartzite, taking its name from Swede pond. 

 It is probably several hundred feet thick. This is overlain by another 

 limestone bed of crumbly texture or " sandy " to which no dis- 

 tinctive name has been applied. 



It is followed by a sillimanite schist which the writer calls the 

 Catamount schist, 3 then by a para-amphibolite designated as the 

 Beech Mountain amphibolite. 



The footwall of the ore is extremely characteristic. It is a 

 bluish green rock with purple garnets as large as peas. It has been 

 found to be the footwall here, at the Hague mine, at the Hooper 

 mine and many other localities. When examined under the micro- 

 scope it is found to contain, besides quartz, feldspar and garnet, 

 long slender needles of the mineral sillimanite. In the literature 

 it is spoken of as a garnet-sillimanite (para-) gneiss. 4 The term 

 "Hague" gneiss seems to be highly appropriate and will be used 

 here. It is some 50 or 60 feet thick on the Faxon property but 

 decreases in thickness toward the east. 



Beneath is a rock that appears to be a granite but is not a simple 



1 The Mineral Industry for 1890, p. 383. Kemp, J. F., & Newland, D. H., 

 51st Ann. Rep't, N. Y. State Mus., 2:539, fig. 4, section. 



2 Noted by Kemp & Newland, 51st Ann. Rep't, N. Y. State Mus., 2: 539. See 

 the Mineral Industry for 1898, p. 383. 



3 See description of the Bear Mountain pond region and the property of the 

 International Graphite Company. 



4 51st Ann. Rep't, N. Y. State Mus., 2:530. Microphotograph. 



