By Joe Dase MTU Mining Engineer on Tuesday, June 29, 2004 - 06:45 pm:
Carl- Most of the Lodes in the area are steep dipping, but think of this... how far does the Calumet Conglomerate extend, or the Osceola, or the Kearsarge??? The length of the Keweenaw, and therefore it is possible that there are undiscovered deposits, i.e.-St. Louis. The problem is not depth, underground mining costs for some underground mining methods are under $12/ton, the problem is information. Too little was preserved, all the old exploration data gone, and remember that the price of copper is not the only thing that dictates the income of an operation, but silver as well, as silver is found in high grades in some areas. Also Lake Superior plays no role in water levels in the mines, the water table is independent of lake levels, and a mine will fill to the surface usually unless it has a spot to drain from, besides inflow in many of the mines is almost non existent realistically, it all occurs shallow in the weathered bed rock and in the spring time, remember how long it took Quincy to fill to the adit level? That mine has LOTS of openings, and it took over 50 years to fill. There is a company doing exploration work in Houghton County currently, south of the portage, keep our eyes open and you might see the airplane doing recon, but if I had to bet I would say any deposits developed in the future will be sulfides and not native formations.
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