Z PROCEEDINGS OF THE NATIONAL MUSEUM vol. 74 



ever, that it was in southern Utah and thus about 300 miles, air line, 

 from the Wyoming occurrence. His description of the occurrence is 

 as follows: 



The tschermigite and jarosite occur iiitermiugled at the top of a butte on 

 the top of a hard sandstone bluff 200 feet high. The minei'al-bearing structure 

 is approximately 100 feet high with a more or less rounded contour 1,500 feet 

 in diameter. It is located 20 miles from the nearest good road * * *. Will 

 say that this deposit lies on the western slope of the Kaibab (also called vari- 

 ously Pahreah, Potato Valley, or Kaiparowitz) fault. The top of the butte 

 is covered with about 1 foot of the " egg-shell " stuff which is being sent 

 you. Additional samples of the minerals are also being sent. 



Of the samples received as associated material, the most abundant 

 is a grayish clay which contains obscure fragments of what may be 

 plant remains. This disintegrates in water in a manner suggesting 

 that it is largely bentonitic in character. Scattered through the 

 samples and intimately associated with the ammoniojarosite are 

 some obscure fossils which were provisionally identified as Ostrea 

 glabra and CorhuJa fei^ndata by Dr. John B. Reeside. These fix 

 the age of the beds as upper Cretaceous. 



The paligorskite and celestite are inclosed in friable red sandstone 

 similar to that of the Triassic " Red Beds." 



DESCRIPTION OF THE MINERALS 



TSCHERMIGITE 



The ammonia alum, tschermigite, was first described by Beudaunt 

 under the name "ammonalaun " - as occurring in fibrous veins 

 in the lignite of Tschermig in Bohemia. The name tschermigite was 

 given to the substance by von Kobell in 1853. Aside from the 

 Tschermig locality and one in a mine at Dux, also in Bohemia, the 

 mineral has been more recently described as occurring in cubic 

 crystals at a mine in Brux, Bohemia, by Sachs.^ In all of the Bo- 

 hemian localities the mineral is associated with lignitic coal. It has 

 also been found as a volcanic sublimate at Mount Etna and at Sol- 

 fatara at Puzzuoli. 



The first American occurrence of the ammonium alum noted was 

 3 miles south of Wamsutter, Wyo. This material has been 

 analyzed and described by Erickson.* The mineral occurs in a 

 6-foot bed of ligTiitic shale and the ledge is traceable along the brinlc 

 of the hills for nearly 3 miles. The tschermigite forms fibrous veins 

 and cements shale fragments, nodules of yellow jarosite, and a few 

 scattered gypsum crystals. 



2 Traite de Miueralogie, vol. 2, p. 497, 1832. 



*Centralbl. Mineralogip, 1907. p. 465. 



* E'. Theodore Erlckson. Joura. Wash. Acad. Sci., vol. 12, pp. 49-54, 1912. 



