1904.] WHARTON — PALLADIUM (Pd). 333 



The form in which palladium there occurs has not been 

 detected, for owing to its minute quantity and the consequent diffi- 

 culty of isolating it, none has yet been directly observed in any ore 

 of ihat region; since, however, platinum occurs there as arsenide 

 in the interesting mineral sperrylite (Pt,As 2), palladium may 

 exist in similar combination, though none has been observed in 

 any specimen of sperrylite that has been examined. Prof Horace 

 L. Wells indeed notes a trace of palladium in sperrylite, but this 

 has not I think been confirmed in any of the careful analyses of 

 other good chemists. 



In the one mine where platinum-arsenide has been found, Prof. 

 Wells says it occurs in small pockets of decomposed rock at the 

 contact of ore and rock, these pockets being filled with loose 

 gravelly material. It was in the metallic sparkles of that sandy stuff 

 where the sun's rays struck it that Mr. Sperry first noticed what 

 proved to be platinum-arsenide — a substance till then unknown. 



Ten years ago, when I visited the mine in question, the Ver- 

 million Mine, I observed, upon the surface of the ground where the 

 ore had been dumped, a moderate quantity of sand which appeared 

 to have resulted from the disintegration and metasomatism of ore by 

 atmospheric penetration, and this seems to afford a plausible expla- 

 nation how palladium-arsenide might have been present in the ore 

 with platinum-arsenide and yet no palladium be now detectible in 

 the Sperrylite ; for the greater oxidability of palladium may have 

 led to the conversion of its arsenide into arseniate, afterward 

 leached away by the percolating water. 



Though the Vermillion Mine is not at present in operation, it 

 affords, as above stated, the only indication we have as to the prob- 

 able condition of both platinum and palladium in the ores of other 

 mines in that region from which those metals are extracted, though 

 neither metal has been directly observed in any of those other mines. 



The ore from those other mines is not simply nickeliferons 

 pyrrhotite, but is also to a considerable extent chalcopyrite, 

 yielding therefore much copper, as well as nickel and minute 

 proportions of the above-named precious metals. The ores of the 

 various mmes in the Sudbury region may be reckoned as containing 

 1% to 8 per cent, of nickel Tsome small quantities even 30 to 40 

 per cent.) and i to 4 per cent, of copper. 



Those ores are roasted in open heaps and then smelted into matte 

 containing by average about 30 per cent, of nickel and copper, 



