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NEW YORK STATE MUSEUM 



The mining of graphite is a small hut firmly established industry 

 which gives promise of steady growth for some time to come. The 

 graphite obtained from the deposits is of superior grade and is 

 readily marketable. Several new companies are now operating in 

 the Adirondacks, where the main deposits are found. The output 

 of graphite in 1905 amounted to 3.897.616 pounds valued at $142,948. 



The talc mines in St Lawrence county supplied 67,000 short 

 tons, about the same quantity as in 1904. The production is gov- 

 erned by the requirements of the paper trade and shows little 

 fluctuation from year to year. 



APATITE 



Apatite is a crystallized form of calcium phosphate. It contains 

 when pure about 90 per cent of tricalcium phosphate and 10 per 

 cent of calcium fluorid which may be replaced by calcium chlorid. 

 It is a common constituent of igneous and metamorphic rocks, par- 

 ticularly granites, gneisses and crystalline limestones, but it occurs 

 in greater abundance in dikes and veins and in association with 

 iron ores. 



The principal uses of apatite are in chemical manufacture for the 

 preparation of phosphoric acid, phosphate of lime and artificial 

 fertilizers. Competition with rock phosphate, which is found in 

 large deposits in many parts of the world, has restricted the mining 

 of apatite, and the output is confined practically to the few localities 

 where it is associated with other valuable minerals. Both apatite 

 and rock phosphate are sold on the basis of content in calcium 

 pHosphate (bone phosphate), as determined by chemical analysis. 

 The former ordinarily contains a higher percentage of this com- 

 ponent, so that it is preferred for preparations entailing expensive 

 processes of manufacture. 



In New York State, apatite has been produced for several years 

 by Witherbee, Sherman & Co., of Mineville. The mineral is dis- 

 seminated in small grains through the magnetite found at that 

 locality, paricularlv in the deposits of the Old Bed group. It 

 frequently forms 5 per cent or more of the ore, in which it is con- 

 spicuous by reason of its reddish color. To render the iron ore 

 suitable for smelting, a partial elimination of the apatite is neces- 

 sary, and this is accomplished by crushing and passing the ore over 

 magnetic machines. Two separations are made, the first yielding 

 a concentrate that carries about 65 per cent iron and a tailings 

 product consisting of magnetite, hornblende, apatite and quartz. 



