lis Butler and SohaUer — Minerals from Beaver Co., Utah. 



Art. XLIV. — Some Minerals from Beaver County, Utah}* 

 by B. S. Br ti.kk and AV. T. Schaller. 



Introduction. 



While making an examination of some of the mines in 

 Beaver County, Utah, in the summers of 1909 and 1910, one 

 of the writers, B. S. Butler, collected several minerals that on 

 examination proved to be of unusual interest. One of these is 

 a species not hitherto known, a second has never before been 

 reported from this continent, and a third, although previously 

 reported from but two localities, was found to be relatively 

 abundant in this district. 



Beaver ite, a New Mineral. 



From the Horn Silver mine near the town of Frisco was 

 collected a mineral that on examination in the laboratories of 

 the United States Geological Survey proved to be a new species. 

 For this mineral, which is a hydrous sulphate of copper, lead 

 and ferric iron, the name beaverite is proposed, after the name 

 of the county from which it was first described. 



Occurrence. — The mineralization in the Horn Silver mine 

 occurs along a fault plane that has thrown Tertiary lavas down 

 against Cambro-Ordovician limestone, the ore deposits being 

 mainly a replacement of the volcanic rocks. 



The principal primary minerals of the deposit are: Galena, 

 sphalerite, wurtzite, pyrite, chalcopyrite, a sulph-antimonite 

 of lead possibly jamesonite, pyrargyrite, argentite, quartz, 

 barite, muscovite, and small amounts of other minerals. 



The mine has been developed to a depth of 1C00 feet. For 

 about 600 feet the primary minerals have been almost entirely 

 altered by descending solutions, and this alteration has. taken 

 place in a lesser degree to a much greater depth. The charac- 

 teristic alteration in the deposit is to sulphates with some car- 

 bonates, chlorides and sulphides. 



The following secondary minerals have been recognized : 

 Anglesite,cerussite, plumbojarosite, jarosite, beaverite, linarite, 

 bindheimite?, smithsonite, calamine, goslarite, covellite, chal- 

 cocite, brochantite, malachite, azurite, chrysocolla, chalcanthite, 

 cerargyrite, sulphur, chalcedony, kaolinite, gypsum, alunite, 

 and hydrous oxides of iron and manganese. 



The beaverite occurs with other secondary minerals in the 

 upper part of the deposit. Only a small portion of the upper- 

 levels was accessible at the time of the visit and the mineral 



* Published by permission of the Director of the U. S. Geological Survey. 



