SILVER AND GOLD. . 201 



2.09.04. Example 22a. Atlantic Border. Already mentioned 

 (2.05.02), the region is only of historical interest as affording sil- 

 ver, although lately some attention has been directed to Sullivan, 

 Me., where the veins have pyrite and probably stephanite, in a. 

 quartz gangue, in slates, associated with granite knobs and trap 

 dikes which are of later age than the veins. Some silver is gener- 

 ally found in the galena of the Eastern States, but the ores have 

 never yet proved abundant enough to be important. 1 



Mention may also be made at this point of the argentiferous 

 galena veins along the Ouachita uplift of Arkansas. A few are 

 known, usually with Trenton shales or slates for walls. They are 

 low grade, and though once the basis of a small excitement, their 

 production has never been serious. Additional reference to the 

 region will be found under "Antimony." Some mines of the lat- 

 ter metal are stated by W. P. Jenney to show low-grade, argentif- 

 erous ores in depth. 2 



2.09.05. Example 42. Silver Islet, Lake Superior. A fissure 

 vein carrying native silver, argentite, tetrahedrite, galena, blende, 

 and some nickel and cobalt compounds in a gangue of calcite, in 

 flags and shales of the Animikie (Cambrian) system, and cutting 

 a large trap dike, within which alone the vein is productive. 

 Silver Islet is or was originally little more than a bare rock some 



ous Forms in which Gold Occurs in Nature," Pep. Director of the Mint, 

 1884, p. 573. Rec. Brown, Raymond, and others, 1868 to 1876, "Mineral 

 Resources West of the Rocky Mountains." Annual. T. C. Chamberlain, 

 "On the Geological Distribution of Argentiferous Galena," Geol. of Wis., 

 Vol. IV. Clarence King, "Production of the Precious Metals in the 

 United States," Second Ann. Rep. Director U. S. Geol. Survey, p. 333. A. 

 G. Lock, Gold, 1882. Mineral Resources of the U. S.; annual publication of 

 the Geological Survey. R. I Murchison, "General View of the Conditions 

 under which Gold is Distributed," Quar. Jour. Geol. Soc., VII. 134. Also 

 in Siluria and Amer. Jour. Sci., ii., XVIII. 301. J. S. Newberry, "On the 

 Genesis and Distribution of Gold," School of Mines Quarterly, III., No. 1, 

 and Engineering and Mining Journal, Dec. 24 and 31, 1881, pp. 416, 437. 

 R. Pearce, "On the Ores of Gold,'' etc., Colo. Sci. Soc., III., p. 237. J. A. 

 Phillips, Ore Deposits, 1884. The Mining and Metallurgy of Gold and 

 Silver, 1867. Tenth Census Report on the Precious Metals. 



1 C. %\ Kempton, "Sketches of the New Mining District at Sullivan, 

 Me.," M. E., VII. 349. M. E. Wadsworth, "Theories of Ore Deposits," 

 Proc. Boston Soc. Nat. Hist., 1884, p. 205. Engineering and Mining Jour- 

 nal, May 17, 1884. Bull. Mus. Comp. Zodl, 3, Vol. VII., 181. 



2 T. B. Comstock, Ann. Rep. Geol. Survey of Arkansas, 1888, Vol. I., 

 " Gold and Silver." 



