Composition of some Norwegian Minerals. 



65 



weighed 2*99 grains. It gave the reaction of titanic acid be- 

 fore blowpipe, but evidently contained columbic acid, as it be- 

 came bright yellow on ignition, while it was of the usual colour 

 when cold. I am not acquainted with any means of separat- 

 ing these acids completely. 



The solution was now precipitated by ammonia, and the 

 precipitate filtered off and carefully washed. In the filtrate a 

 small amount of lime and magnesia were respectively deter- 

 mined by oxalate of ammonia and phosphate of ammonia. 



The precipitate itself was dissolved in hydrochloric acid, 

 rendered as nearly neutral as possible by ammonia, and pre- 

 cipitated by oxalate of ammonia — a white precipitate fell which 

 was collected and washed. The washings at first went milky 

 through the filter, but it was found that it could be prevented 

 by adding a few drops of oxalate of ammonia to the wash 

 water. 



This precipitate was ignited, dissolved in hydrochloric acid, 

 and the cerium separated by sulphate of potash, filtered off 

 and determined as usual. The yttria was precipitated by 

 ammonia from the solution and dried. It then weighed 9-24 

 grains, but as it did not look well I re-dissolved it and again 

 precipitated, when it was found to weigh only 6-11 grains, so 

 that the first precipitate was evidently a basic salt. 



The filtrate from the precipitation of the oxalates was now 

 precipitated by hydrosulphate of ammonia, — and this precipi- 

 tate after solution in nitrohydrochloric acid was treated with 

 potash to separate alumina, and the uranium afterwards sepa- 

 rated from the iron by carbonate of ammonia. 



The following results were thus obtained : — 





Grains. 



Employed in analysis, 



. 20-81 



Loss on ignition — reckoned as water, 



0-60 



Columbic acid, 



803 



Titanic acid (with some do.), 



2-99 



Carbonate of lime, 



•51 



Phosphate of magnesia, 



•11 



Alumina, 



•65 



Sesquioxide of iron, 



•46 



Oxide of uranium, 



1-13 



Yttria, . 



6-11 



Sesquioxide of cerium, 



• -73 



. I. NO. I. — JAN. 1855. 



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