174 THE VERMILION IRON-BEARING DISTRICT. 



in sec. 25, T. 63 N., R 12 W.; sec. 30, T. 63 N., R 11 W.; sees. 3 and 

 4,T. 61 K, E. 15 W.; sees. 7 and 8, T. 62 N., R. 14 W.; sec. 6, T. 62 N., 

 R. 14 W., and sec. 1, T. 62 N., R. 15 W.; the exposures are very poor. But 

 the fact that the exposures of the iron formation are scarce and small in some 

 localities does not necessarily mean that the formation at such places is not 

 now or may not become in the future of very great economic importance. 

 For example, the immensely valuable iron deposits at Ely, extending from 

 the Chandler mine on the west to the Savoy on the east, occur where jasper 

 exposures are remarkably few. 



In the belts traced through the district the exposures are small and 

 discontinuous, both along and across the strike, and this would make it 

 impossible to trace out any horizons in the iron-bearing formation, even if 

 they could be determined, but, owing to the uniformity of the formation, 

 such horizons can not be fixed. In making use of the accompanying maps 

 it should be clearly understood that the colors or patterns indicate merely 

 that the iron formation has been found in the areas so colored. The limits 

 fixed do not necessarily imply that the area is underlain wholly by the 

 formation, for, as has ah-eady been intimated above, in many instances 

 exposures of greenstone, equally as numerous and as large, occur in these 

 belts in intimate association with the jaspers. With these occur also 

 younger intrusives, which cut through them-. In fact, it is impracticable to 

 say which of these two kinds of rock preponderates in many of such areas. 

 The iron-bearing formation certainly does preponderate in a number of the 

 well-known areas which will at once occur to those acquainted with the 

 district — for example, on Tower and Lee and Soudan hills, Jasper Peak, 

 ridge in sec. 25, T. 63 N., R. 12 W., and ridge in sec. 30, T. 63 N., R. 11 W. 

 The above statement will hold true, however, on the whole, for the smaller 

 belts. The belts outlined represent the possible ore-bearing areas, and 

 siTch areas having once been outlined as closely as possible by the geolo- 

 gist, it then remains for the mining companies to make more detailed studies 

 of them than it was possible for the members of the Survey to make in the 

 limited time at their disposal. 



In the course of the field work the occurrence of the iron formation 

 has been reported from various localities, but search failed to reveal expo- 

 sures in these places. It is highly possible that in the future other areas 



