MAGNETITE AND PYRITE. 125 



2.03.06. South Mountain, Penn. Small lenses of magnetite oc- 

 cur in Berks, Bucks, and Lehigh counties of southeastern Pennsyl- 

 vania, in the metamorphic rocks of the South Mountain belt. They 

 are very like those to the north in New Jersey, but are lower in 

 both iron and phosphorus. Their product is about 100,000 tons 

 yearly. The Cornwall magnetite is described under Example 13, 

 for its geological structure is entirely different from the lenses. 1 



2.03.07. Example 12c. Western North Carolina and Virginia. 

 Beds of magnetite, of the characters already described, in Archaean 

 gneisses and schists. The ore body at Cranberry, N. C., is the lar- 

 gest and best known. It occurs in Mitchell County, and has lately 

 been connected by rail with the lines in east Tennessee. Accord- 

 ing to Kerr, the principal outcrop is 1500 feet long and 200 to 800 

 feet broad ; but, of course, all of this is not ore. The mines can 

 afford very large quantities of excellent Bessemer grade. Pyrox- 

 ene and epidote are associated with the ore. Kerr has referred the 

 magnetite to the Upper Laurentian. In the southern central por- 

 tions of North Carolina other magnetites occur in the mica and tal- 

 cose schists, which have been referred to the Huronian. Specular 

 hematite is associated with them. (Example 10.) Magnetite has 

 also been lately reported from Franklin and Henry counties, Virginia, 

 and Stokes County, North Carolina, which may be available in the 

 future. Some doubt, however, is cast on its amount and quality. 2 



Dike at the Forest of Dean Mine," Amer. Jour. Sci., iii., XXXV. 331. 

 F. H. McDowell, " The Reopening of the Tilly Foster Mine," M. E., XVII. 

 758 ; Engineering and Mining Journal, Sept. 7, 1889, 206. F. S. Ruttman, 

 " Notes on the Geology of the Tilly Foster Ore Body, Putnam County, 

 New York," M. E., XV. 79. Rec. J. C. Smock, Bull. VII., N. Y. State 

 Museum. Rec. A. F. Wendt, " The Iron Mines of Putnam County," M. E., 

 XIII. 478. "Iron Mines of New Jersey," School of Mines Quarterly, iv., 

 III. N. L. Britton, Ann. Rep. N. J. Survey, 1886, p. 77. Rec. G. H. 

 Cook and J. C. Smock, Geol. of N. J., 1868. Rec. (See also subsequent 

 annual reports, especially 1873, p. 12.) F. L. Nason, Ann. Rep. N. J. 

 Survey, 1889. Rec. J. W. Pullmann, "The Production of the Hibernia 

 Mine, New Jersey," M. E., XIV. 904. J. C. Smock, "The Magnetite Iron 

 Ores of New Jersey," M. E., II. 314 ; " A Review of the Iron Mining In- 

 dustry of New Jersey," M. E., June, 1891. Rec. 



1 E. D'Invilliers, Rep. D3, Penn. Survey, Vol. II. (South Mountain 

 Belt of Berks County). Rec. F. Prime, Rep. D3, Vol. I. Penn. Survey 

 (Lehigh County). B. T. Putnam, Tenth Census, Vol. XV., p. 179. 



2 W. C. Kerr, Geol. of N. C., 1875, 264. H. B. C. Nitze, " On Some of 

 the Magnetites of Southwestern Virginia, etc., and Discussion of Same, 

 by E. C. Pechin," M. E., June, 1891. B. Willis, Tenth Census, Vol. XV., 

 p. 325. Engineering and Mining Journal, Jan. 7, 1888. 



