A. J. R. Atkin — Genesis of Gold Deposits, Barkerville, B.C. 515 



quality than any found in the adjacetit reefs. In the deposits the 

 source of which I have tried to indicate, the very reverse of these 

 conditions may be said to exist. 



The general characteristics of these old channels, that is the filling 

 of the ancient creek beds, consist of — 



1. Pre-Tertiary gravels in the bottom.^ 



2. Tough clay containing striated boulders and pebbles, with 



streaks of pre-Tertiary gravels washed from upper portions 

 of the creek during recessions of the ice-cap. 



3. Recent superficial deposits. 



4. No wood has been found in the channels. 



The gravels in the creek bottoms are the harder detritus from the 

 hill-sides, the softer having been disintegrated and removed by the 

 heavy rains of later Tertiary times. 



The gold occurrence has always been in the type of a deposit 

 sorted in rapidly moving water. 



The heavier and rougher pieces at the top become smaller and 

 more water- worn as the creek is followed down from its source, while 

 behind some of the larger boulders a remarkable concentration of 

 gold has taken place. 



The fineness of the gold varies in different creeks; and it can 

 always be recognised, even when mixed, as below the junction of 

 two channels. 



In some instances different parts of the same creek were dis- 

 tinguished by varying grades of gold, while in one case there was 

 a noticeable increase in returns below a large quartz reef, although 

 this reef itself is now valueless, and the richness varied along the 

 channel. This instance should be given due prominence when 

 considering the possibility of a detrital or accretionary origin for 

 the gold. 



All the specimens submitted are from one creek. The larger 

 nuggets, y, =2", etc., are from the upper portion, those marked B 

 are from the middle,*whil6 the smaller grains in the vial C are from 

 the lowest ground worked. 



It will be noticed that the specimens from the head of the creek 

 are large and not much worn, y scarcely at all, while |, y are 

 typical specimens of quartz gold such as may be chipped from any 

 rich outcrop at the present time. 



Specimen B is from a boulder found in Snowshoe Creek. This 

 rock weighed over 250 lbs., and was extraordinarily rich. It shows 

 gold intimately associated with iron pyrites and also in the quartz 

 alone. Had this rock experienced sufficient attrition to set free the 

 gold we would have had nuggets like f, |^, etc., while the smaller 

 pieces might have travelled further down the creek to become 

 similar to the inbits B and C. 



Specimen E contains gold panned by the writer from a quartz 

 outcrop on Lowhee Creek, which would have yielded nuggets similar 

 to those now found in the placers had the outcrop been eroded 

 sufficiently. 



1 See section. 



