Geology 



The action of the streams had carried away most of 

 the lighter minerals, resulting from the denudation of the 

 granite and gneiss, but the tin-stone had been concen- 

 trated in every little pool and hollow of its bed, so that 

 it could be gathered in large quantities even by hand. 

 This promised to be the most easily workable portion 

 of the tin-field, and could certainly be wrought at a 

 handsome profit which might be used in opening up the 

 rich veins on the south slope of the Granite Mountains. 



The belt of weathered gneiss intersected by tin veins 

 continued for some two miles from the edge of the 

 granite mass, but became gradually more normal as the 

 boundary was left behind. The excessive weathering of 

 this belt of gneiss was the result of changes effected in 

 its mineralogical character during the intrusion of the 

 granite, both by the agency of heat and the action of 

 the pneumatolytic gases. 



The deposits of tin-stone were for the most part 

 confined to this metamorphic aureole, though in the 

 neighbourhood of some of the quartz-porphyry dykes 

 considerable quantities occurred beyond its limits. 



The investigation of these matters had carried us 

 some distance to the east of Tin Creek, and we therefore 

 determined to strike out across country for the head 

 waters of Gold Creek, and to return by that stream 

 instead of by the main valley. 



On reaching Gold Creek, and travelling a few miles 

 down its valley, we came upon a group of quartz-veins 

 all bearing iron-pyrites and a little gold. These we 

 were able to trace in a north-easterly direction until they 

 entered and traversed an area of highly metamorphosed 

 schists. A careful examination of this area failed to 



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