STRUCTURAL RELATIONS OF THE ORE BODIES. lo3 



schistose diorites and a brecciated condition of the gneiss and quartz-syenite. 

 The Evans mine appears to be connected with a continuation of this break. 

 A number of more or less promising occurrences of the mixed ore have 

 been found in the two southern ranges of Denison, in Louise, Lome, Nairn, 

 Baldwin, Drury and Hyraan, and further north in Neelon and McKim. All 



Figure I— Section of brecciated Ore from Murray Mine. 



these are associated with diorite. In some instances they have been found 

 to be connected with lines of fracture, and this may prove to be so in all 

 cases. The discoveries of the ore which have been made to the west of Lake 

 Wahnapitse are also in diorite in the vicinity of quartz-syenite. 



Mode of Occurrence of the Ores. 



The various occurrences of the mixed nickeliferous pyrrhotite and chal- 

 copyrite, as far as they have yet been opened up, all resemble each other so 

 closely that a description of one will apply to all. They are associated 

 primarily with the diorite masses which conform more or less nearly with 

 the general strike of the other rocks of the country. The older lines of frac- 

 ture or disturbance are also approximately parallel with the strike, but their 

 planes may incline at different angles from the local dip. The ore-bodies 

 take the form of stock- works, following the direction of these ancient faults. 

 Tiie bodies are made up of a mixture of the country rock and the sulphides 

 in the shape of a confused mass of coarse and fine fragments of the former, 

 while the ore itself constitutes the matrix or filling between them. The frag- 



XX— Bum,. Gkol. Soc. Am., Voi,. 2, 1890. 



