414 Jamieson — Natural Iron-Nickel Alloys. 



These results differ but slightly from those obtained by 

 Melville, who found iron 23*22, nickel 60*45, and 15-83 per 

 cent of other constituents. The metals calculated to 100 per 

 cent equal, iron 27*75, and nickel 72*25. 



The sample of iron-nickel alloy which came from Smith 

 Kiver, California, was in the form of grains of remarkably 

 uniform size, about 0*15 millimeters in diameter, with an occa- 

 sional larger grain, up to 1*5 millimeters. The metallic sand, 

 for that is what it appears to be, was obtained from gold 

 washings and was chiefly composed of the alloy, but mixed 

 with magnetite, and a very little chromite. As no mechanical 

 method for separating the alloy from the magnetite seemed to 

 give satisfaction, a separation by chemical means was again 

 resorted to. The size of the grains, which could not be 

 reduced to powder, made the solution in iodine altogether too 

 slow for practical purposes. The alloy was found, however, 

 to be easily soluble in warm dilute nitric acid (one part cone. 

 HN0 3 : two parts H 2 0), while the magnetite was not appreci- 

 ably attacked, if at all. Duplicate analyses were made with the 

 following results : 



Insoluble matter 9*45 9*97 



Iron 19-21 18-97 



Nickel 68-61 68*46 



Cobalt 1*07 1-07 



Copper "59 "56 



Sulphur *05 '05 



Phosphorus *04 -04 



Silica *10 *19 



Magnesium oxide *50 -44 



99-62 99-75 



The specific gravity was found to be 7*45 or, allowing for 

 9*7 per cent of magnetite, the value 7*85 is obtained for the alloy. 

 Deducting the insoluble matter, consisting of the magnetite, 

 a small amount of chromite and the traces of silica and magne- 

 sium oxide, and recalculating the remaining constituents for 

 one hundred parts, the following percentages were obtained : 



Iron 21*45 21*28 



Nickel 76*60 76*79 



Cobalt _.. 1*19 1*20 



Copper ___ *66 *63 



Phosphorus '04 *04 



Sulphur -06 -06 



100-00 100*00 



In dissolving the alloys in hydrochloric acid, it was noted 

 that there was no odor of hydrocarbons, such as is observed 

 when iron and steel are dissolved, nor was there any evidence 

 of graphitic carbon. 



