74 Diorites and Granites of Swift's Creek, 



retained. From here the auriferous deposits extend only a 

 short distance up the Sheep Station Gully, but have been 

 continuous along Riley's Creek up to the point where it 

 crosses the southern contact of the diorites and the Silurian 

 formation, at which place the creek ceased to be payable. 

 Throughout its course Riley's Creek follows more or less 

 along the line of contact of some highly-altered sediments 

 and the diorites which have intruded into and metamorphosed 

 them. Sheep Station Gully, on the other hand, flows almost 

 entirely on the quartz diorites. Here, again, we have an 

 indication of some connection between the source of the 

 alluvial gold and the contacts of the igneous and sedimen- 

 tary strata. 



I need not enter into fuller particulars as to the occurrence 

 of the alluvial gold, which would be of little interest. 



5. The Auriferous Quartz Veins. 



Quartz reefs have been more or less mined upon at Swift's 

 Creek for many years, but are now, with one or two 

 exceptions, abandoned. I give a tabulated statement of 

 all the data which I have been able to collect as to the width 

 of the quartz veins, the depth to which they have been 

 worked, the amount of stone crushed, and the yield per ton. 

 The statistics which can still be obtained are unfortunately 

 very scanty. Those given have been compiled from the 

 returns published by the Mining Department, and from viva 

 voce statements made to me by persons who have been 

 engaged in working the several mines.* An inspection of 

 these tabulated data and an inspection of the map show : — 



1. The gold-bearing reefs, with the exception of the 

 Caroline (now Duke of Cornwall), are all situated on or in 

 immediate proximity to the line of contact of the intrusive 

 and sedimentary rocks. 



2. That they are narrow, and have become unproduc- 

 tive, or have " wedged out" at or under 200 feet from the 

 surface. 



The gangue of these reefs is almost invariably quartz, but 

 rarely, as at Eureka, it was — for instance, in the Renovator 



* In collecting these statistics I must express the great obligation I am 

 under to Mr. W. Phipps, mining registrar at Omeo, and to Mr. Thomas 

 Easton, J.P., of Omeo, who was formerly engaged in mining adventures at 

 Swift's Creek. 



