274 KEMPS ORE DEPOSITS. 



interstices ; lastly, a mixture of quartz and feldspar as a core. 

 Other tin-bearing granites occur as dikes, or veins, as much as 80 

 feet wide, and bearing the so-called greisen and tin ore in quartz. 

 They are called segregated veins by Carpenter, who doubts their 

 igneous character, probably on good ground. No tin is yet com- 

 mercially produced. The tin deposits extend also into Wyoming. 1 



2.15.15. Tin ores as stream tin have been found in gold wash- 

 ings in Montana and Idaho. Tin is also known in the Temescal 

 Mountains, southern California, and according to Blake is in 

 various small veinlets in a granite region. This locality attracted 

 much interest years ago, but has never yielded any practical re- 

 sults until lately. Operations after being carried on for a time 

 have, however, proved a failure. 2 



2.15.16. Narrow veins carrying cassiterite are being exploited 

 in the granite and schistose rocks of Rockbridge and Nelson 

 counties, Virginia, in North Carolina, and in Alabama. Compa- 

 nies have been formed to work the two former, but as yet without 

 a notable output. 3 w 



2.15.17. Cassiterite has been discovered in narrow veins in mica 

 schists with lepidolite and fluorite at Winslow, Me., and is known 

 at other places in Maine and New Hampshire. A salted tin pros- 

 pect several years ago spread the impression that tin was to be 

 found in southwest Missouri.* 



1 W. P. Blake, Mineral Resources, 1884-85, p. 602. Rec. Amer. Jour. 

 Sci., September, 1883, p. 235 ; Engineering and Mining Journal, Sept. 8, 

 1886. "Tin Ore Deposits of the Black Hills," M. E., XIII. 691. F. R. 

 Carpenter, Prelim. Rep. Dak. School of Mines, 1888 ; also 711. E., XVII. 

 570. "Tin in the Black Hills," Engineering and Mining Journal, Nov. 

 28, 1884, p. 353. Mineral Resources of the U. S., annually under " Tin.'' 



2 W. P. Blake, "Occurrence of Wood Tin in California, Idaho, and 

 Montana," Mining and Scientific Press, San Francisco, Aug. 5, 1882. H. 

 G. Hanks, Rep. Cal. State Mineralogist, 1884, p. 121. 



3 H. D. Campbell, " Tin Ore, Cassiterite, in the Blue Ridge in Vir- 

 ginia," The Virginias, October, 1883. A. R. Ledoux, " Tin in North Caro- 

 lina," Engineering and Mining Journal, Dec. 14, 1889, p. 521 ; see also 

 February, 1887, p. 111. McCreath and Platt, Bull. Iron and Steel Asso., 

 Nov. 7, 1883, p. 209. W. Robertson, London Mining Journal, Oct. 18, 1884. 

 A. Winslow, "Tin Ore in Virginia," Engineering and Mining Journal, 

 November, 1885. Rec. 



4 W. P. Blake, Mineral Resources, 1884, p. 538. C. H. Hitchcock, 

 "Discovery of Tin Ore and Emery at Winslow, Me.," Engineering and 

 Mining Journal, Oct. 2, 1880, p. 218. T. S. Hunt, " Remarks on the Oc- 

 currence of Tin Ore at Winslow, Me.," M. E., I. 573. C. T. Jackson, " Tin 

 Ore tit Winslow, Me.," Proc. Bost. Soc. Ndt. Hist., XII. 267. 



