Jamieson — Natural Iron-Nickel Alloys. 413 



Art. XL1II. — On the Natural Iron-Nickel Alloy, Awaruite • 

 by George S. Jamieson. 



Two terrestrial iron-nickel alloys from adjoining localities 

 will be described in this paper. One from Josephine Co., 

 Oregon, which has already been investigated by Mr. W. H. 

 Melville,* came through Mr. Maynard Bixby of Salt Lake 

 City, Utah. The other, found at South Fork, Smith River, 

 Del Norte Co., California, was from Dr. David T. Day, Chief 

 of the Division of Mining and Mineral Resources of the United 

 States Geological Survey. Both specimens had been sent to 

 Professor S. L. Penfield, at whose advice this investigation was 

 undertaken. 



The specimens from Josephine County were water-worn, 

 bean-shaped pebbles, varying in size from a few millimeters to 

 two centimeters in diameter and were composed not only of the 

 alloy, but also of more or less siliceous matter. Thin sections 

 showed that the alloy was of a spongy nature, binding together 

 and enclosing particles of silicate, which had the appearance 

 of serpentine and gave the chemical reactions for that sub- 

 stance. In a steel mortar, the pebbles were easily broken into 

 a powder and no mechanical method of making a separation of 

 the metal from the serpentine seemed possible. A chemical 

 separation, however, was easily effected by treating the powder 

 with water and iodine at ordinary temperature. A complete 

 solution of the alloy was thus obtained in about a day, while 

 the siliceous matter was not dissolved by this treatment. The 

 insoluble silicate was filtered on asbestos, air dried, and weighed. 

 Duplicate analyses were made with the following results : 



Insoluble silicate 24*15 24'55 



Iron 19-17 18-95 



Nickel .56-30 56*07 



•Cobalt __ . _ -35 -35 



Phosphorus -04 -04 



Sulphur -09 -09 



100-10 100-05 



Deducting the insoluble silicate and recalculating the remain- 

 ing constituents to one hundred parts, the following percent- 

 ages were obtained : 



Iron 25-24 25-11 



Nickel 74-17 74*30 



Cobalt -46 -46 



Phosphorus -04 -04 



Sulphur ... _.. -09 -09 



100-00 100-00 



* This Journal [3], xliii, 509. 



