264 DEPARTMENT OF TEE INTERIOR 



2 GEORGE V., A. 1912 



occurs in masses of workable size. No reliable information was obtained on 

 the ground as to the values found in assayed specimens of the sulphide's, but 

 the material collected from the prospect-dumps nowhere suggested the possi- 

 bility of a high-grade property. On the other hand, the small size and com- 

 parative rarity of the bunches of ore shows that no known claim in the ' camp^ 

 can prove successful as a low-grade mine. 



Petrography of Belt C. — In width, length, and axial trend, belt C is very 

 similar to belts A and B. In composition C is, in some respects, like A but 

 does not seem to bear any dolomitic bands. The most complete section across 

 belt G was made at the summit of North Star mountain. Elsewhere in the 

 belt, exposures are very poor and it is very possible that the boundary lines, 

 especially that on the eastern side, are drawn too straight. This third belt is 

 composed essentially ,of well and thinly foliated phyllites, chlorite-sericite 

 schists, and phyllitic biotite-sericite schists, all tending toward a dark greenish 

 gray colour. Within these staple rocks there occur strong bands of a very 

 dark gray intensely sheared quartzite. The quartzite bears abundant little 

 foils of sericite and biotite, disseminated in planes of schistosity. The inter- 

 locking, metamorphic quartz grains are full of opaque black dust which may 

 be driven off before the blow-pipe and is probably carbon in graphitic or other 

 form. This carbonaceous matter is abundant and explains the dark colour of 

 the rock in ledge or hand-specimen. A few sheared quartz pebbles were found 

 in the phyllite on North Star mountain near the western limit of the belt. 



Wherever outcrops were found in the belt the attitude of the planes of 

 schistosity corresponds well to the average attitude in belts A and B. Through 

 most of the belt the strike varies from N. 7° E. to N. 10° W. ; the dip averages 

 about 75° E. At one locality near the summit of North Star mountain, the 

 dip of the schistosity plane was 75° E. Such discordance appears, however, 

 to be local and, in general, the planes of bedding and schistosity may be nearly 

 coincident. The schists do not extend beyond the Dewdney trail and seem to 

 be cut off by the same transverse fault which has been postulated to explain 

 the failure of belt B north of the trail and so marked on the map. 



Petrography of Belt D. — The fourth belt is dominantly quartzitic. The 

 quartzite is normally more or less sheared. Both biotite and sericite are largely 

 developed, in fact never failing entirely in this metamorphosed sedimentary. 

 Within the quartzite beds are numerous, though thin intercalations of sericitic 

 and chloritic schists along with beds of dolomite. The quartzites are of com- 

 pact texture and vary in colour from white to pale greenish-gray, weathering 

 white or buff. They are often charged with accessory grains of carbonate, 

 which qualitative analysis shows to be probably typical dolomite. The same 

 mineral is also an abundant accessory in the chlorite and biotitic schists, The 

 study of thin sections seems to show that much, perhaps all, of the chlorite 

 found in the schists is secondary after biotite and after the rather rare garnets 

 which sometimes appear among the accessories. 



