THE KECOVEEY OF POTASH PROM ALUISTITE. 3 



The altmite described by these writers, however, is mainly the 

 pink variety, crystalline or cryptocrystaHine, coming chiefly from a 

 lai^e banded vein cutting the volcanic rock at a high elevation about 

 7 miles southwest of Marysvale. The samples of alunite used in the 

 following experiments were a light colored variety showing little or 

 no crystalline structure and some of it containing considerable amounts 

 of siHca. These samples came from two deposits ^ about 10 miles 

 north of that described by Butler and Gale. One appears to be a 

 very wide vein between two rhyoHte dikes. The other has the ap- 

 pearance of an enormous outcrop, one wall of rhyolite well defined. 

 The geological features, however, have not as yet been worked out 

 in detail. 



LOCATION, EXTENT, AND ACCESSIBILITY OF THE UTAH ALUNITES. 



While a number of occurrences of alunite of minor importance have 

 been reported ^ by the United States Geological Survey, the most im- 

 portant deposits described ^ are those occurring in the Tuscar moun- 

 tain range at the head of Little Cottonwood Canyon from 7 to 8 miles 

 southwest of Marysvale, Piute County, Utah. (See fig. 1.) 



The lower end of this deposit is fuUy 4,000 feet above Marysvale, 

 the present terminus of the San Pete Branch of the Denver & Rio 

 Grande Railroad. This branch connects with the main fine of the 

 Denver & Rio Grande at Thistle, about 100 miles north of Marysvale. 



Butler and Gale have estimated the amount of high-grade alunite 

 in one group of claims (to a depth of 100 feet) at 300,000 tons. 

 Loughlin * in a later examination of some other properties in this 

 region increased this estimate of high-grade alunite to 474,900 tons. 



About 2 miles north of Marysvale begins the Sevier Canyon. The 

 Sevier River runs between steep and often sheer banks rising from a 

 few feet to several hundred, the banks being backed by mountains 

 rising in some cases as high as 2,000 feet above the river bed. The 

 canyon is about 14 miles long and on both sides for a distance of 8 or 

 10 miles north of Marysvale and a distance of 3 or 4 miles on each side 

 of the river it has been very actively if not thoroughly prospected 

 for alunite, a great many locations having been made within the last 

 two years. Some fine masses of the typical pink or pinkish crypto- 

 cr\'stalline varieties have been found, though usually these are so 

 located as to make their exploitation difficult. But a large area of 

 light-colored material has also been discovered, some of which is of 



I The geological data and geographical location of the deposits of light-colored alunite were furnished by 

 Dr. F. K. Cameron, formerly of this bureau, to whom the writers are alsoindebted for a number of valuable 

 suggestions. 



* Phalen, W. C, Mineral Resources, pp. 9-33, U. S. Geol. Survey (1913), 



' Butler and Gale, Bull. .511, U. 8. Geological Survey (1912). Loughlin, G. F., Bull. C20-K, U. S. Geo- 

 logical Survey (1915). 



* Bull. 02f>K U. S. Geological Survey (1915). 



