Centre Valley Tin Ore 



all along the line of junction between the granite and the 

 gneiss we found numerous rich tin-bearing veins. As 

 we approached Tin Creek, however, a change came 

 over the nature of the deposits, and in Tin Creek itself 

 we found the following conditions prevailing. The 

 veins were not so well marked, and both the granite and 

 gneiss near the line of their junction appeared to have 

 been crushed and fractured. They had been largely 

 converted into greisen, and were intersected in all 

 directions by thin veins of tin-stone associated with 

 tourmaline and axinite. 



It was from these wide areas of rock more or less 

 impregnated throughout by tin-stone that the rich 

 alluvial deposits of Tin Creek, presently to be described, 

 had been derived. 



Having passed the head of Tin Creek we proceeded 

 to investigate the northern flank of the granite mass, 

 but on this side there appeared to be fewer mineral 

 veins, and these were not nearly so rich as the ones we 

 had previously examined. We therefore returned to 

 the head of Tin Creek, intending to make our way to 

 the main valley by this route and to return to Three 

 Forks Camp. 



Having left the granite mass and entered the gneiss 

 area, we encountered a large dyke of quartz-porphyry 

 running nearly parallel to the stream. In this dyke 

 many of the large felspar crystals had been entirely 

 replaced by tin-stone, and there were considerable 

 masses of secondary quartz containing needles of blue 

 tourmaline. The gneisses in the neighbourhood of the 

 dyke were in a highly decomposed condition and were 

 wasting rapidly under the action of the weather. 



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