Schoolcraft on the Copper of Lake Superior. 45 



from the main land, forming a route of communication 

 which is generally passed in light canoes. There is a por- 

 tage of only two hundred and seventy-five rods from the 

 source of this river, to the shore of the lake west of the 

 point, and the distance saved by the route is commonly es- 

 timated to be ninety miles. 



This is the channel pursued by the expedition through 

 the upper lakes in 1820, and consequently we were preclu- 

 ded from making any personal observations upon the ex- 

 tremity of that point of land. Heavy barges, such as are 

 usually employed by the fur traders, cannot, however, cross 

 this portage, but are compelled to keep out in the open 

 lake. In traversing around this peninsula, they must pass 

 a small bay and point of rock known among the Canadian 

 boatmen by the name o{ La Roche Verie, which is, in fact^ 

 the vein of copper ore, of which specimens are sent, where 

 it juts out abruptly upon the lake. 



The person whom I employed to procure these speci- 

 mens left this place early in the month of May last, but hav- 

 ing other pursuits likewise in view, did not return until with- 

 in a short time. He reports, that the vein of ore is about 

 one fathom in width, rising with a broken, hackly surface 

 out of the water, and that it extends in a direct line from 

 the lake into the interiour — its course being marked upon 

 the bed of the lake by a broad green stripe reflected through 

 the water, and upon the shore by parallel walls of the 

 enclosing rock, which constitutes the matrix of the ore. 

 He further represents that this peninsula rises into conical 

 mountains of considerable elevation, and that the strata fre- 

 quently show themselves in precipitous cliffs upon the wa- 

 ter's edge. From the specimens of this formation which 

 lie before me, and the best information I have been able to 

 procure, I am led to conclude that the entire peninsula con- 

 sists of a spine of granite, with sandstones, amygdaloid, aqd 

 secondary trap deposited around its base. The soft, red- 

 dish brown, ferruginous rock, which exists in connexion 

 with the ore, is probably allied to the former strata. No 

 experiment has been made to determine the quality of the 

 ore. It appears from external characters, to be the com- 

 pact Malachite of authors which is stated generally to yield, 

 at the mines of Cornwall and Saxony, from fifty-six to sev- 

 enty percent, of oxid of copper, the remainder being chief- 



