1880.] NATURAL SCIENCES OF PHILADELPHIA. 275 



The proportion between the lime and uranium may be given as 

 follows : 



Koenig. Rand, 1. Rand, 2. 



Lime, 50 38 26 



Uranium, 44 G2 14 



10.708 gm. of coated rock, after treatment with acetic acid, 

 yielded to 8 p. c. liydrochloric acid, cold, in about five minutes 

 (the coating having disappeared), .122. On evaporating the 

 solution to dryness there was a residue less than .001 gm. The 

 solution Avas precipitated by ammonia, in the presence of chloride 

 of ammonium ; the solution with oxalate of ammonia gaA'^e car- 

 bonate of lime, .0365. The precipitate treated with acetic acid 

 dissolved wholly, except .001 of a white precipitate, which con- 

 tained phosphoric acid, and was probably phosphate of alumina. 

 The solution pi-eeipitated by phosphate of soda gave jjhos. uran., 



.0711 =U20;, .0569. 



Per cent. 



Uranic oxide, .0569 46.71 



Lime, .0204 16.71 



Phos. al? .001 .89 



Undetermined, 35.69 



100. 



About 100 grams of the rock, free from the coating, were treated 

 with acetic acid in excess. A large amount of lime was dissolved, 

 and a trace of alumina. The residue, treated with hydrochloric 

 acid, yielded a little silica, some alumina, and considerable lime. 



I infer from these tests that the mineral has not the composition 

 obtained b}^ Dr. Koenig, and that further investigation is needed, 

 if pui'e material can be obtained. 



