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direction nearly coincident with that of the ridge. It is into one 

 of these great clefts that the waters of the Passaic precipitate 

 themselves at the Falls. 



In the red sandstone between East and West Bloom field, green 

 carbonate of copper is occasionally seen, but always in the form 

 of a very thin film or crust, filling the minute seams and divi- 

 sional joints of the rock, and never but in very inconsiderable 

 quantity. 



At several points in the neighbourhood of New Brunswick, ores 

 of copper have been found; and prior to the revolutionary war, 

 an extensive and costly attempt was made to establish a mine 

 here, but without success. The red shale is in many places coated 

 by the blue and green carbonates of the metal, in the form nearly 

 of a thin pellicle. In a few instances the metal occurs in the pure 

 state, soft and malleable, in the shape of a thin plate, injected 

 into the body of the rock, rarely more than the twentieth of an 

 inch in thickness. In every such case, the contiguous rock is 

 more or less indurated, as if by heat; and in immediate contact 

 with the vein of metal, its ordinary brownish-red colour is 

 changed to a light-gray for the thickness of a third of an inch or so. 



The Franklin Copper Mine, near Griggstown, in Somerset 

 county, is situated on the western declivity of a hill, whose sum- 

 mit is occupied by trap rock, but up the side of which the shale 

 rises to a considerable height. It is in this shale, which is consi- 

 derably altered by the trap, that the copper ore has been found. 

 The mine is in a dilapidated condition, and no longer accessible. 

 Judging from the character of the materials brought out from the 

 mine, and from the testimony of those who were familiar with it 

 when open, the excavation runs for some distance horizontally 

 through an altered shale of a dark purple colour, which becomes 

 afterwards paler and more siliceous. The ore occurs diffused 

 through this altered shale. Occasionally it has the aspect of existing 

 in very narrow short strings, or little veins of injection, being in 

 such cases mixed with carbonate of lime, felspar, hornblende, and 

 other minerals, constituting what approximates to a true metalli- 

 ferous gangue. The best ore found here is a soft blue sulphuret, 

 associated always with carbonate of lime ; but the principal 

 species is the usual carbonate of copper and the red oxide, min- 

 gled through the altered shale, which abounds in little geodes or 



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