﻿188 



Canadian Record of Science. 



containing very little nickel as an element replacing 

 The following analyses will show this tendency : 



iron. 



Copper Cliff Mine. 



Depth in feet. 



Per cent, of Total 

 Ni in Pyrrhotite. 



Per cent, of Total 

 NiinPentlandite. 



Picked Ni ore 



Surface. 



51.7 

 34. 

 29. 



18 



48.3 

 66. 

 71. 

 82 





600 

 700 



800 



11 X 



>> t( 











In samples of ore of the same percentage in nickel, 

 taken from different depths in the deposit, the nickel 

 separates as an- individual mineral more perfectly as the 

 depth increases, or, in other words, at those points in the 

 deposit where, if the igneous theory be true, the ore has 

 remained longest in the molten condition, and better 

 opportunity has been offered for physical and chemical 

 separation. 



We have now seen that an agreement in the method of 

 arrangement of the elements exists between the ores and 

 mattes along the following lines : — 



1. The tendency of copper in both ores and mattes is to 

 rise vertically upward and accumulate at the surface, and 

 also, 



2. To travel horizontally outward from the centre and 

 accumulate on the outer cooling surfaces. 



3. The tendency of nickel in both ores and mattes is to 

 sink vertically toward the centre, and also, 



4. To leave the outer cooling surfaces and to travel 

 liorizontally inward toward the centre. 



5. In both ores and mattes the separation of nickel in 

 the lower part of the deposits as an individual mineral 

 sulphide is in direct proportion to the fluidity of the mass 

 and the length of time occupied in cooling. 



It does not seem possible to explain this parallelism by 

 any other theory than this ; that the nickel deposits 

 of Sudbury existed primarily as eruptions of molten 

 sulphides mixed with the constituents of the- dioritic 



