30 NEW YORK STATE MUSEUM 



The active mines in the Adirondacks are situated in Essex and 

 Warren counties. The North River Garnet Co., with mines and mill 

 on Thirteenth lake. Warren county, southwest of North River, is 

 the principal producer and carries on operations more or less con- 

 tinuously throughout the year. The garnet occurs in disseminated 

 crystals in a hard, gneissoid hornblende — feldspar rock which has 

 to be crushed and subjected to mechanical separation to recover 

 the mineral, the separation being complicated by the slight differ- 

 ence in the gravity of the garnet and hornblende. The separation 

 is effected mainly by jigs of special design and results in a very 

 clean concentrate, with such variation of sizes as is required for 

 abrasive purposes. The deposit, situated on the side of a mountain. 

 is attacked by open-cut quarry methods which by reason of its large 

 size and convenient position admit of great economy in breaking 

 and transporting the rock. 



The next most important source of garnet is on Gore mountain, 

 a little west and south of North Creek, and some 4 or 5 miles 

 southeast of the former deposit. The garnet here occurs in a band 

 of dark hornblende gneiss, forming larger crystals than are found 

 anywhere else in the Adirondacks. They measure a foot or even 

 more in maximum diameter. The band of garnet gneiss is relatively 

 narrow and is worked in open pits. The rock is broken down by 

 sledges and the garnet, which has been shattered by regional com- 

 pression, is readily picked out of the matrix by hand. These quar- 

 ries are worked only in the open season. They are operated by 

 H. H. Barton & Son Co. of Philadelphia. 



Some production has been made from time to time from Garnet 

 peak, in the town of Minerva, Essex county, about 3 miles from 

 North River, on the Indian Lake road. The garnet is in small 

 srystals, but plentifully distributed through the rock. In years past 

 the American Glue Co. has been active at this locality, but made 

 no output in 19 12. 



The Warren County Garnet Mills. Inc.. of Riparius. have recently 

 been active at a locality near Wevertown. south of North Creek. 

 The mineral here is quite different in appearance from that pro- 

 duced in the other mines of this section, being partly granular or 

 compact, rather pale in color, and lacking the tendency to break 

 with smooth surfaces which is characteristic of the crystal garnet. 

 It is also more or less intergrown with a green pyroxene. The 

 material is hand-sorted and prepared for market by grinding to 

 proper size. 



