a 



NATIVE PLATINUM FEOM BRITISH COLUMBIA. 19 



(I. /'. c. 



Platinum 81-18 67-85 57-95 



Palladium 0-30 0-34 0-17 



Rhodium 2-56 4-09 2-93 



Iridium 1-09 1-92 0-87 



Osmium .••. ••-• 



Copper 2-96 3.82 2-75 



Iron 8-90 8-03 6-95 



Osmiridium 2-17 12-50 25-96 



Gangue (imbedded chromite) 1-06 1-74 2-79 



100-22 100-29 100-37 



Specific gravity 17-811 17-562 16-126 



The osmiridium of .sub-portiou a was iu the form of minute steel-grey colored scales 

 of bright metallic lustre, with au occasional microscopic, tin-white, compact grain. That 

 of sub-portion b consisted of a heavy, light steel-grey colored powder, very fine steel- 

 grey colored scales of brilliant metallic lustre, a few microscopic, tin-white, irregular 

 shaped, compact grains, and some six or seven tin-white cavernous nodules, varying in 

 size from two to three millimetres in diameter. Whilst that of sub-portion c consisted in 

 part of a heavy, light steel-grey colored powder, some very fine steel-grey colored scales 

 of brilliant metallic lustre, some tin-white, minute, often almost microscopic, tolerably 

 firm skeleton aggregations of minute scales, and a few tin-white, cavernous nodules, one 

 of which measured almost five millimetres in diameter. The grains and nodules of 

 osmiridium amounted to about fifty-five per cent, of the whole of that constituent, and 

 had a specific gravity of 18t42. 



Adding together the weights of the material constituting the above three sub-portions, 

 as likewise those of each of the various coustitutents found, calculation showed the 

 composition of the non-magnetic portion of the ore, as a whole, to be as follows : — 



Platinum 68-19 



Palladium 026 



Rhodium 3-10 



Iridium 1-21 



Osmium 



Copper 309 



Iron 7-87 



Osmiridium 14-62 



Gangue (imbedded chromite) 1.95 



100-29 

 Specific gravity 17-017 



Portion II. — Magnetic. 



Weighed 6-119 grams, and had a specific gravity, as a whole, of 16-095, and was, as 

 already stated, magneti-polar. 



Agreeably with the method of selection adopted in the case of the non-magnetic 

 portion, this portion became separated into two sub-portions, d and e. 



Sub-portion d. — Weighed 2>-W6l grams, and had a specific gravity of 16-*789. It was 



