128 KEMP'S ORE DEPOSITS. 



2.03.12. Example 14. Iron County, Utah. Beds of mag- 

 netite and hematite bearing evidence of being metamorphosed 

 limonite, in limestones of questionable Silurian age, and associated 

 with eruptive rocks described as trachyte. The limestones have 

 been much upturned, metamorphosed, and pierced by dikes and 

 eruptive masses. The ore forms great projecting ridges and prom- 

 inent outcrops, locally called " blow-outs." The usual lenticular 

 shape is not lacking. They occur over an area of fifteen by five 

 miles, and are in the southern end of the Wasatch Mountains. 

 The samples show rich ores, which at times exceed the Bessemer 

 limit of phosphorus. In the Star district the ore apparently lies 

 between quartzite and granite. Hematite occurs in large amount, 

 as does quartz, while some streaks have large crystals of apatite. 

 The importance of the deposits lies in the future. They are the 

 largest in the West, and are interesting in their bearing on the 

 general origin of magnetite. Coal, not proved to be good for 

 smelting, is near, but centers of iron consumption are very far 

 away. 1 



2.03.13. Example 15. Magnetite Sands. Beds of magnetite 

 sands concentrated on beaches or bars by waves and streams. 

 The magnetite has been derived from the weathering of igneous 

 and metamorphic rocks, through which it is everywhere dis- 

 tributed. When in the sand of a sea beach, it and other heavy 

 minerals tend to be concentrated by the sorting action of the waves. 

 They resist the retreating undertow better than lighter materials. 

 Such deposits are very abundant at Moisie, on the St. Lawrence, 

 below Quebec, and in the United States are known in smaller de- 

 velopments on Lake Champlain ; at Quogue, L. I.; on Block 

 Island ; in Connecticut ; along the Great Lakes, and on the Pacific 

 coast. Grains of garnet, olivine, hornblende, etc., minerals of high 



Also Penn. Survey, Rep. C2. E. V. D'lavilliers, "Cornwall Iron Ore 

 Mines," M. E., XIV. 873. Rec. Lesley and D'lnvilliers, Ann. Rep, Second 

 Penn. Survey, 1885. J. P. Lesley, Final Report, Vol. I., p. 351, 1892. Rec. 

 T. S. Hunt, "The Cornwall Mines," etc., M. E., IV. 319. H. D. Rogers, 

 First Penn. Geol. Survey, II. 718. B. Willis, Tenth Census, Vol. XV., p. 

 223. Rec. 



1 W. P. Blake, "Iron Ore Deposits of Southern Utah," M. E., XIV. 

 809. J. S. Newberry, " Genesis of Our Iron Ores," School of Mines Quar- 

 terly, March, 1880. Rec. Engineering and Mining Journal, April 23, 

 1881 , p. 286. Proc. National Academy, 1880. B. T. Putnam , Tenth Census, 

 Vol. XV. 486. Rec. 



