148 



KEMP'S ORE DEPOSITS. 



but passed into chalcopyrite below. Wendt also mentions a, 

 group of veins in granite that likewise afforded chalcocite. 1 



2.04.21. Example 20#. The Bisbee district, called also the 

 Warren district, is situated in the Mule Pass Mountains in 

 southern Arizona, near the Mexican line. The range runs east and 

 west and consists of beds of Lower Carboniferous limestone, dip- 

 ping away from a central mass of porphyritic rock. The ores are 

 found in the canons on the south side, which have been formed 

 by erosion, along the contact of the limestone and porphyry. 

 They are of the same oxidized character as at Morenci, and in the 



FIG. 38. Section of Copper Queen ore. body Bisbee. district, Arizona. 

 After A. F. Wendt, M. E., XV. 52. 



important mines occur in the limestone. The ore-bearing solutions 

 seem to have spread out chiefly along the bedding planes and to 

 have replaced the limestone at a distance from the contact. The 

 ore bodies leave great chambers when excavated and partake of 

 the nature of bedded veins. Empty caves occur associated with 



1 J. Douglass, " Copper Resources of the United States," M. E., Sep- 

 tember, 1890. Rec. " Arizona Copper and Copper Mines," Engineering 

 and Mining Journal, Aug. 13, 1881, p. 103. " Clifton Copper Mines of Ari- 

 zona," Ibid., Feb. 21, 1880, p. 133. C. Henrich, " The Copper Ore Deposits 

 near Morenci, Ariz.," Ibid., March 26, 1887, pp. 202, 219. Rec. A. Wendt, 

 " Copper .Ores of the Southwest," M. E., XV., p. 23. Rec. 



