194 



and 38 m.) respectively. On the north limb are a few- 

 small breaks. A few fiat faults having the nature of thrusts 

 have also been met in underground workings. The 

 faults do not continue for great distance on the strike nor 

 in depth and are later than the formation of the veins, 

 but the Baker vein in the eastern part of the district 

 occupies a fault plane cutting the anticline at right angles 

 which is of earlier origin and probably greater extent in 

 depth than the other faults. 



CHARACTER OF THE GOLD DEPOSITS. 



With the exception of the Baker vein which has been 

 proved highly auriferous, all the veins worked in the district 

 are of the interbedded type and are called leads. They 

 follow fractures or slips along stratification planes and 

 occur chiefly in beds of slate interstratified between beds 

 of quartzite. The outcrops of the veins form almost 

 complete concentric ellipses curving sharply at the western 

 end and broadly at the eastern end of the dome. Over 25 

 interbedded veins have been worked and traced more or 

 less continuously on both the north and south limbs of the 

 dome. The vein-bearing zone is thus confined to the dome, 

 on which it extends 8,100 feet (2,470m.) east and west 

 along the anticlinal fold and 1,600 feet (485 m.) across it. 



The most productive part of the district is the eastern 

 end of the dome, where the pitch of the anticline increases 

 rapidly from o° to 45 , causing there the maximum amount 

 of fracturing across and along the stratification plane which 

 produced rolls, corrugations and angulars favourable to ore 

 deposition. 



Amongst the most important interbedded veins may be 

 mentioned the Dunbrack, Sterling, Boston-Oldham, North 

 Wallace, South Wallace, and Donaldson. A great number 

 of others have been worked and many of them with profit. 



The most important ore-shoots follow the rolls, which are 

 quite prominent in the veins in the southeastern part of the 

 district and pitch to the east at approximately the same 

 angle as that of the pitch of the anticline. On the Dim- 

 brack lead a very persistent and rich ore-shoot was worked 

 to a depth estimated at 1,200 feet (356 m.) on a pitch 

 increasing gradually from 5 to 40 . The rich ore-shoot 

 which in 1909 averaged 2-88 ounces of gold per ton in the 

 Sterling Barrel lead on the apex of the anticline has been 



