BUTLER AND SCHALLERI BEAVERITE 



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sphalerite, wurtzite, pyrite, chalcopyrite, jamesonite (?), pyrar- 

 gyrite, argentite, quartz, barite, sericite, and small amounts of 

 other minerals. 



To a depth of about 600 feet the primary minerals have been 

 almost entirely altered by descending solutions and this altera- 

 tion has taken place to a lesser extent to a much greater depth. 

 The characteristic alteration is to sulphates with some secondary 

 carbonates, chlorides, and sulphides. 



The following secondary minerals have been recognized: 

 Anglesite, cerusite plumbojarosite, jarosite, beaverile, linarite, 

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

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

 cerargyrite, sulphur, chalcedony, kaolinite, gypsum, hydrous 

 oxide of iron and manganese, and alunite (?). 



Beaverite commonly occurs mixed with other secondary min- 

 erals but occasionally is found pure in small, friabls masses. It 

 is canary yellow in color and crystallizes in six-sided plates too 

 small for measurement of the angle or determination of the opti- 

 cal character. Minute inclusions, whose character has not been 

 determined, are present in nearly every crystal. 



The mineral is soluble in boiling hydrochloric acid leaving an 

 insoluble silicious residue. The analysis and ratios are as follows : 



Analysis of beaverite 

 W. T. Schaller, analyst 



The ratios agree well with the formula CuO.PbO.Fe ; 3 .2SO s . 

 4H 2 0. The water is all constitutional as none was driven off 

 below 250°. There is no known mineral to which beaverite 

 is related so that at present it stands as an isolated member of 

 the sulphate group. 



