148 



S. BADCLIFF. 



a b c 



Ferrous oxide 17*37 16*9 



Manganous oxide ... ... 0*24 trace 0*11 



Thorium oxide 0*13 



Cerium oxide 1*26 4*68 



Lanthanum and didymium oxide 2*13 3*27 



Yttrium oxide 1*16 



Chromium sesquioxide ... ... 1*6 0*85 



Uranoso uranic oxide 2*25 1*6 49*95 



Vanadic oxide 0*93 0*86 0*02: 



Titanium dioxide 51*85 45*85 



Silica 1*15 12*70 18*54 



Zinc oxide 1*09' 



Phosphoric oxide 0*33 



Sulphur 5*08 



Arsenic 0*44 



Bismuth 0*24 



Copper '... 0*89 



Iron ... 8*04 



Carbon dioxide 5*02 



The ore is dry crushed at the mine to pass a sieve of 20 

 holes to the linear inch, and is then concentrated mag- 

 netically; the concentrates, amounting to about 30 per cent, 

 of the ore crushed being forwarded to Sydney for treatment. 



One of the most interesting points about analysis (a) is 

 that the ratio of the uranium to the thorium is as 16*7 : 1 ; 

 radium preparations worked up from this ore should there- 

 fore contain very little mesothorium. This conclusion has 

 been confirmed in Rutherford's laboratory by Dr. Alexander 

 Russell who examined a specimen of the bromide and found 

 it to contain as radio-active substances only radium and 

 its decomposition products. 



As the concentrates are insoluble in acids, a fusion pro- 

 cess is necessary to effect the initial decomposition. The 



