E. T. Wherry — New Occurrence of Carnotite. 575 



Chemical Composition. 



Material for analysis was obtained by scraping off the 

 coating from a specimen of rather friable conglomerate, and 

 contained accordingly considerable amounts of quartz, as well 

 as some limonite and kaolin. As the yellow substance proved 

 to be entirely soluble in dilute nitric acid, while the greater 

 part of these impurities are insoluble, this seemed adequate for 

 the purpose in hand. Uranium and vanadium were determined 

 by the method of Campbell and Griffin,* which was first tested 

 on known solutions of the metals and found to give very 

 accurate results. Iron and calcium were obtained in the usual 

 ways, water by loss on ignition, and potassium, by difference. 

 Barium, lead, and phosphoric acid could not be detected with 

 certainty ; the strong radio-activity of the mineral indicates 

 the presence of radium, although its amount is of course too 

 small to be estimated, while lack of material also prevented 

 establishment of the presence of helium. 



The analytical results are given in the first column of the 

 accompanying table, and the figures obtained by deducting the 

 insoluble matter, iron oxide and water, and recalculating the 

 remainder to 100 per cent, in the second. The iron is certainly 

 present as limonite, and while a part of the water may belong 

 to the carnotite, the amount in this form is indeterminate, so 

 it is best disregarded in calculating the formula. The results 

 are given in the first decimal place only because of the unsatis- 

 factory character of the sample. Most of this work was carried 

 out, under the direction of the writer, by Mr. J. S. Long of 

 Lehigh University, to whom much credit is clue for skilful 

 handling of the problems presented. 





A 



nalysis 



1 



7'2 

 23-8 

 6-1 

 1-5 

 [1-6] 

 105 

 49-3 



and Ratios. 



2 



21-1 

 69-8 



4-4 

 4-7 



Eatios 





V 



•116 

 •243 



•050 j Zy 



1 00 



25 



uo 3 



FeO 





2-09 



CaO 



K 2 0(diff.) ... 

 HO 





1-11 



Insoluble 







100-0 100-0 



Without attempting to place undue confidence in these 

 results, it cannot be denied that they show a tendency to 

 approach a definite ratio, (Ca,K 2 )0.2U0 3 .V 2 5 , or (Ca,K 2 ) 



* Jour. liid. Eng. Chein., vol. i, pp. 661-665, 1909. 



