6 METEORIC IRON, OWENS VALLEY, CALIF.— MERRILL. '""""'"v^xix 



For the HC1 insoluble residue the remaining 25 grams of the material furnished were 

 digested similarly with HC1 and the residues combined, giving a sample amounting to the residue 

 from 75 grams of the original material. Iron, nickel, cobalt, phosphorus, carbon, and silica 

 were found. There was obtained a very slight precipitate of ammonium chloro-platinate show- 

 ing a trace of platinum to be present. Moreover, this precipitate was somewhat brownish in color 

 indicating a trace of iridium. Tests showed no palladium, osmium, ruthenium, nor rhodium in 

 amounts sufficient for detection by wet method. Further negative results were obtained on 

 making tests for all the other metals mentioned as being found absent in the HC1 solution. 



In the quantitative work 25 gram samples were used for the metals, 10 grams for each 

 sulphur and total phosphorus, and 5 grams each for the combined and graphitic carbon. The 

 following results were obtained: 



Percent. 



Iron 55. 15 



Nickel 30. 09 



Cobalt 0. 67 



Phosphorus 13. 06 



Per cent. 



Silica 0. 15 



Platinum Trace. 



Iridium Trace. 



Total 99.12 



It is evident that this is largely one of the variable compounds to which the name schreiber- 

 site is commonly applied. 1 



Carbon determinations run on the original sample showed : 



rcr cent. 

 Combined carbon 0. 019 



Graphitic carbon 013 



All the graphitic carbon would be in the acid insoluble part and probably most of the com- 

 bined as cohenite. 



The material soluble in HC1 showed the following composition : 



Percent. 



Iron. 91. 65 



Nickel 7. 80 



Cobalt 0. 46 



Phosphorus 0. 007 Total 100. 047 



From the accumulated residues from the HCl treatment a sample corresponding to 75 

 grams was obtained and this was found to contain 0.0008 gram platinum, the brown color of 

 the ammonium chloro-platinate precipitate indicating iridium, though attempts to effect a 

 separation were unsuccessful. 



Per cent. 



Sulphur 0. 13 



Copper 2 Trace. 



1 A study of the phosphide question as so admirably summed up by Cohen (Meteoritenkunde, B. 1, S 124), coupled with experience gained in 

 my own work as mentioned in a previous paper (Mem. Nat. Acad. Sci., vol. 14, 1910, p. 10) has led me to the conclusion that the rhabdite alone 

 has a definite crystallographic form and a chemical composition that can be expressed accurately by the formula ( FeNiCo) 3 P. The forms com- 

 monly described under the name schreibersite are but solid solutions of rhabdite in varying amounts of iron as in artificial iron and steel (see 

 Sauveur, The Metallurgy and Heat Treatment of Iron and Steel, p. 144). In this way only, as it seems to me, can we account for the imperfect 

 development of crystal faces and the continual vanation in the proportional amounts of iron and phosphorus shown in the large series of analyses 

 now available. I hope soon to be able to say more upon this subject. I can not wholly agree with Cohen in ascribing the discrepancies shown 

 to impure material or poor analyses. 

 'Less than 0.001 per cent. 



