302 JOSEPH STRUTHERS 



acid and potassium chlorate; diamond is unaltered, and 

 amorphous carbon (charcoal) is complete^ dissolved, but 

 graphite is converted into a compound known as graphitic 

 acid or graphitic oxide (C11H4O.J). 



As a fact of mineralogical interest, but one which has no 

 industrial importance, it may be mentioned that meteoric 

 masses have been found containing graphite which in its 

 properties resembles the graphite formed during the cooling 

 of high carbon and pig iron. 



Crystalline graphite is widely distributed throughout the 

 United States, but the known deposits of sufficient extent 

 and purity to warrant working on a commercial scale are 

 few in number. During the past decade the domestic output 

 of high grade crystalline graphite has been obtained chiefly 

 from the mines near Ticonderoga, Essex county, N. Y. The 

 mines in Chester county. Pa., were reopened in 1897, after 

 a long period of inactivity, and have been in continuous 

 operation since that time. In 1899 the mines in Clay county, 

 Ala., produced a small amount. There has been considerable 

 activity in the exploitation of graphite properties in Bartow 

 county, Ga.; near Dillon, Beaverhead count3% Mont.; in Mer- 

 rimack county, N. H; in McDowell county, N. C. ; at Bloom- 

 ington, in northern New Jersey; and in many localities in 

 California; but up to the present time the work has been 

 confined chiefly to determining the character and extent of 

 the deposits, and to ascertaining by experiment the best 

 method of concentrating the ore so as to convert it into a 

 salable product. The limited number of graphite mines 

 now producing the crystalline variety of the mineral bears 

 witness to the difficulties encountered in the development of 

 a prospect into a paying property. 



The principal mines in New York are at Ticonderoga, 

 Essex county. The graphite is of the foliated variety, oc- 

 curring in minute scales in the cleavage planes of a seam 

 of gray quartzite. The ore contains an average of 10 per 

 cent of graphite, of which but little more than one half is 

 extracted by the prevailing method of working. The graphite 

 bearing bed lies Ijetween strata of massive micaceous gneiss, 



