165 

 MINERALIZATION. 



The argillaceous rocks included in the granites at 

 Granby bay are heavily mineralized at a number of points. 

 The most important deposits so far discovered occur on a 

 low iron-stained hill north of Granby bay, enclosed between 

 two branches of Hidden creek. The deposit has been 

 explored by a tunnel driven straight into the hill for a 

 distance of about 1,000 feet (304 m.), by numerous short 

 drifts, by surface trenching, and by diamond drill boreholes. 

 The mineralized area is proven by the various workings to 

 be of great extent although it has not yet been fully defined. 

 In shape it forms a right angle. The smaller arm, known 

 as the first ore body, has a northeasterly strike and dips to 

 the northwest. It has been traced from the main tunnel* 

 in a southwesterly direction for over 600 feet (183 m.), the 

 width averaging about 160 feet (48 m.) or, including a 

 siliceous band which borders it on the northwest, nearly 

 200 feet (61 m.). The longer arm holding the second ore 

 body has been traced in a northwesterly direction for a 

 distance of 1,500 feet (457 m.) with an average width of 

 about 400 feet (122 m.). The deposit has been proved by 

 a bore-hole to a depth of 514 feet (157 m.) below the main 

 tunnel or approximately 900 feet (274 m.) below the surface 

 outcrops on the hill. 



While only a portion of the large area described con- 

 tains valuable minerals in sufficient quantities to constitute 

 commercial ores, the original rocks are everywhere either 

 completely altered into greenish, or less commonly brownish 

 micaceous schists, or replaced by quartz and iron and copper 

 sulphides. The transition from the dark, slightly altered 

 argillites which constitute the country rocks, is usually 

 fairly abrupt, often occurring in a few inches. 



A conspicuous feature of the deposit is the presence of 

 a zone of whitish quartz schists, practically strongly silici- 

 fied argillites, traceable part way round it. This siliceous 

 zone forms the northwestern boundary of the southwestern 

 or smaller arm, crosses the deposit, then bending at right 

 angles continues to the northwest as the northwestern 

 boundary of the larger arm. It was not observed on the 

 southwest border of the larger arm or the southeastern 

 border of the smaller arm. 



* The examination of the deposit by the author was made in 1911. Since 

 then much additional exploratory work has been carried on. 



