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BATHURST MINES.* 



(G. A. Young.) 



The iron ore deposits of Bathurst Mines occur in three 

 main bodies or groups of bodies, the longer axes of which, 

 at the surface run about north and south. These deposits 

 occur within a limited area on the northern bank of Nipi- 

 siguit river and in the vicinity of Austin brook, a south- 

 easterly flowing tributary of the main river. One of the 

 groups of iron ore bodies known as No. 2 deposit, out- 

 crops on the northeast side of Austin brook valley and 

 extends northward for at least 1,200 feet (360 m.). An- 

 other ore body, known as No. 1 deposit, outcrops on the 

 southwest side of Austin brook valley about 900 feet (275 

 m.) west of No. 2 deposit and extends southerly for several 

 thousand feet. The third group of ore bodies known as 

 No. 3 deposit, lies nearly due north of No. 1 body at a 

 distance of about 800 yards (730 m.). 



In the immediate neighbourhood of the ore bodies, all 

 the rocks are of igneous origin and belong to three main 

 types, namely, quartz-free porphyry, quartz porphyry and 

 diabase. The rocks in the district are largely covered by 

 drift and therefore the relationships existing between the 

 different rock varieties has not been established, but it is 

 assumed that the quartz-free porphyry and the quartz por- 

 phyry are closely related in origin and age and that the 

 diabase occurs in dyke or sill-like bodies cutting the 

 porphyries. 



The quartz-free porphyry outcrops in the eastern and 

 southwestern portion of the area; the quartz porphyry 

 forms the central portion of the area; and the diabase oc- 

 curs in the western portion. No. 2 deposit lies within and 

 just along the boundary between the area of quartz-free por- 

 phyry on the east and the central zone of quartz porphyry ; 

 No. 1 and No. 3 deposits occur along the western margin of 

 the zone of quartz porphyry near the area occupied jointly 

 bv diabase and quartz-free porphyry. 



The quartz-free porphyry is usually of a dark greyish 

 colour, is fine grained, dense, and contains very small 

 phenocrysts of plagioclase feldspar. In most cases the rock 

 has at least an irregular schistose parting and in many 



*See Map, Bathurst Iron Mine. 



