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In a southeasterly direction from the Ophir dock 

 beyond a fishing station and the south end of Sultana 

 island is Needle point, where the ancient traps have been 

 so altered that nearly all trace of their original structure 

 has been lost and they appear as hornblendic and chloritic 

 schists. Just beyond this point is the old Keewatin mine, 



Ellipsoidal trap. Shoal lake. 



where the ellipsoidal character of the trap is well shown 

 as the result of the weathering out of the interstitial 

 material. These ellipsoids, when fresh, are usually light 

 coloured in the middle and dark on the borders, while the 

 interstices are filled with quartz, ferro-dolomite and epidote. 

 Usually the interstitial material is lacking on the weathered 

 surfaces. 



At the south side of Big Stone bay southeast from the 

 Keewatin series, some of the precipitous outcrops of trap 

 show the ellipsoidal structure with the accompanying 

 ferro-dolomite. The best examples lie between high and 

 low water marks. 



Continuing along the south shore of Big Stone bay 

 the route lies through Eagle passage and thence in a south- 



