THE ADIRONDACK GRAPHITE DEPOSITS 120, 



of the layers of slime is further assured by the action of paddles or 

 brushes that are attached to (usually) two horizontal arms secured 

 to the shaft. The revolving brushes lightly rub the surface of the 

 material in the tank and gradually slide up the shaft as the buddle 

 is filled up. The graphite flakes, by virtue of the low specific 

 gravity and flaky, scaly nature, are mainly floated to the sides while 

 the heavier and more massive minerals are dropped near the center 

 of the tank. It usually consumes several hours to fill a single buddle 

 so a series of them are employed ; while one is being filled another 

 is being emptied. 



After the tank is filled, the material is allowed to dry partially 

 and is then shoveled up. The outer portion nearest the wall of the 

 tank is composed of rather clean concentrates. The inner portion, 

 consisting of sand tailings, is rejected, while the middle portion 

 consisting of both graphite and gangue materials, is passed to another 

 buddle for further concentration. Usually two or three buddies 

 comprise the first set and a like number make up the second. 

 Buddies are the favorite form of concentrators in the Adirondack 

 mills ; the amount of labor involved in their use, however, has led 

 a few operators to seek a cheaper method. 



The buddle concentrates must be further treated. The more 

 common process is by the use of revolving screen reels. " The 

 reels are hexagonal and are covered with screens of various sized 

 mesh. The reels are slightly inclined ; the ore is fed into one end 

 and the concentrates thrown out at the opposite end as the reel 

 rotates. Jets of water directed against the outer part of the reel 

 aid in the separation of the graphite and impurities. The latter 

 because of their small size pass through the screens and are thrown 

 away." 1 



The common practice in most mills is to regrind the seconds, to 

 crush the quartz and feldspar grains and send it through the screen 

 again. The graphite is then dried. A number of different types of 

 dryers are in use. Both direct and steam methods are employed. 



The most common one is the rotary tube form, although a number 

 of specially designed dryers were seen. Final sizing on screens 

 divides the concentrates usually into four grades. These are then 

 ready for the finishing mill. 



In some mills, Wilfley jig tables are used, operating upon the 

 buddle concentrates before the reels performed their function. 



Miller, B. L., Topo. and Geol. Sur. of Pa. Rep't 6, p. 87-88. 

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