THE UEKMaN'Jtt GROUP. 



289 



covered partially on the slopes by sediments. On the top of both 

 hills, the sedimentary covering is now about 200 or 300 feet thick 

 and there is no doubt that it once extended right across. On the 

 western margin the granite appears to emerge from the overlying 

 rocks at a high angle while on the eastern margin the angle is much 

 lower. 



About 60 different veins have been worked. They occur in 

 groups which have a general north and south trend and a steep 

 easterly dip. They may be grouped as follows : — ■ 



The general strike of the veins in Big Hill is north-north-east, 

 south-south-west with an easterly dip. On Tin Hill the general 

 strike is north and south with an easterly dip. The exact strikes 

 and dips of a number of the larger veins is given below : — 



New Roof Strike . . .27° E. of X. dipping GS°E. Big Hill 



JS'o. 2 „ „ . 



No. 3 , 



55 Reef ... 



419 ., „ . 



No. 1 „ „ . 



B „ . 



U >t ,, . • . 



Ba Eik Reef „ . 

 Tha Baw „ „ . 



Many of these veins are strongly developed and have been 

 traced on the surface for distances of 500 to 1,100 feet. Like' most 

 other veins in the district they tend to vary considerably in thick- 

 ness and in places to form long, drawn out, overlapping lenses. 

 They continue through from the sedimentary rocks to the gramte 

 and carry both wolfram and cassiterite to the lowest point yet 

 reached, some 400 feet below the contact. Faulting is prevalent 

 and complicated and its general scheme will not be apparent until 

 more underground development has been done. At present all 

 that can be said is that the faults appeal to throw in both direc- 

 tions without any special rule. Certain small fissures of more 

 recent date than the main veins are said to cut them at an acute 

 angle, the faults striking about 10° — 15° more to the east or west 

 as the case may be. The displacements caused vary from a few 

 inches to two feet and there seems to be no enrichment of metallic 

 ores at these points, though this is not always so. The small fissure 

 veins themselves also carry values. 



12 



28° E. of N. 



55°E. 





, f 



22° E. of N. 



88°E. 





it 



25° E. of N. 



75°E. 





»> 



17° E. of N. 



68°E. 





»> 



20° E. of N. 



78°E. 





ft 



1 1° W. of X. 



8G°E. 



Tin 



Hill. 



1° E. of N. 



87°E. 





Ij 



6° E. of N. 



80°E. 





5» 



10° W. ofN. 



83° E. 





II 



