494 /S. L. Penfield — Pentlandite from Sudbury, Out. 



distinct parting was observed only at certain intervals. The 

 attempt to cleave from a given piece an octahedron was not 

 successful and among a great many fragments which were 

 examined only one was found with a distinct octahedral shape. 

 This octahedral parting, rather than cleavage, is perhaps 

 characteristic of the pentlandite from the original locality in 

 Lillehammer, southern Norway. Scheerer in his original 

 article* describes it as follows : " Molecular structure : Foliated 

 parallel to the faces of a regular octahedron. Fracture : in 

 places which show no foliation, line-grained to conchoidal."f 



As the associated pyrrhotite was strongly magnetic the 

 separation of the two minerals could readily be made. The 

 ore was crushed and sifted to a grain of from 1 — 2 mm in 

 diameter and the pyrrhotite was extracted by means of an 

 ordinary magnet. The pentlandite for analysis was further 

 carefully selected by hand picking. The specific gravity of 

 this portion was found to be 5*006. This was so much higher 

 than that given by Scheerer, 4*60, that a second sample was 

 separated which gave 4946. The pure mineral had a pale 

 yellowish bronze color, between that of pyrite and pyrrhotite. 

 The analysis is as follows : 



1047 



99-42 



The gangue was silica which had undoubtedly separated 

 from some decomposable silicate, but no attempt was made to 

 determine the small amount of bases in combination with it. 

 The ratio of S : (Fe + W\) is 1-044 : 1-047, almost exactly 1 : 1 

 or that of a normal sulphide. The ratio of Fe : Ni is 1 : 1*32 

 while in pentlandite from Lillehammer it is about 2 : 1. 



On three supposed new Sidphides of Iron and Nickel from 

 the Sudbury Region. 



Folgerite. 



In a recent number of the Journal of the American Chemi- 

 cal Society,:}: Dr. S. H. Em mens has described as a new species 



*Pogg. Ann, lviii, p. 315, 1843. 



f "Innere Form: Blatterdurch gange parallel den Flachen eines regularen 

 Octaeders. Bruch: auf Stel.len wo sich keine Blatterdurehgange zeigen, fein- 

 kornig in's Musclalige." 



% Vol. xiv, No. 7. 







Ratio. 



s 



... 33-42 



1-044 



Fe 



... 30-25 



•451 



Ni 



... 34-23 



•582 



Co 



•85 



•014 



Gangue . 



•67 





