158 PHILLIPS — RADIUM IX AN AMERICAN ORE. [April 8, 



In October, 1902, I received twenty-five pounds of this ore from 

 Richardson, Utah. Carnotite occurs here in the usual way ; the 

 ore being rather a lean one, no specimens of which carries more 

 than 10% of the mineral carnotite, while the average is greatly 

 below this amount. The percentage content of uranium and 

 vanadium in this ore was not determined, which is to be regretted. 



The radio-activity compared to uranium, as determined by G. 

 B. Pegrara, of Columbia University, was .40. 



After a series of experiments upon a one-pound sample, the 

 remainder of the twenty-five pounds was treated as follows : It was 

 first leached with hydrochloric acid to remove most of the soluble 

 salts ; as radium salts are isomorphous with barium salts, and agree 

 very closely in their chemical properties and solubilities with the 

 similar barium salts, it was thought that strong nitric acid would 

 dissolve the small amount of barmm the ore contained and also the 

 radium with it. 



After the hydrochloric acid treatment the insoluble residue was 

 treated with concentrated nitric ; these two acid solutions were 

 concentrated to small volume. Upon testing them for barium it 

 was found that the precipitate would be small, so it was thought 

 advisable to add a small amount of barium chloride, which would 

 act as a carrier and help in the separation of the small amount of 

 radium present ; sulphuric acid was then added ; the solutions 

 diluted and allowed to stand several days to settle ; the clear solu- 

 tions siphoned off. The resulting sulphates after washing were 

 fused with alkali carbonates. The melt dissolved in water, the 

 insoluble carbonates after washing free of sulphuric acid were dis- 

 solved in hydrochloric acid. Hydrogen sulphide was then passed 

 through the solution to free it of lead. From this solution 

 free of lead the barium was precipitated as a carbonate, and dis- 

 solved in the least possible quantity of hydrochloric acid, when the 

 barium and radium will be in the form of chlorides and are in a 

 condition to concentrate the radium by fractional crystallization. 

 This solution of chlorides was allowed to evaporate slowly until 

 about one-half of the contained salts had separated as crystals, 

 when the crystals were removed, redissolved, the solution again 

 allowed to evaporate slowly until one-half had separated, and so on 

 for a third time, when there was obtained as a final product a little 

 less than one-half gramme of chlorides, the activity of which com- 

 pared to uranyl nitrate was about 1500. 



