In 1870, the rich massive copper had been worked out, and the depth of the mine shafts had reached the limit of the hoisting equipment. At the same time, the price of copper dropped to $0.19 per pound, down from a high of $0.55 in 1864. Rather than invest in new equipment and explore for new ore bodies, the company stopped working the mine, and turned it over to tributer – independent miners who paid for the privilege of mining, usually paying a share of the ore they took out. The mine continued to be profitable to tributers, who took out 270 tons (245 mt) of copper in 1870, the same year that the mine closed. In 1876, the Minesota company paid a final dividend and went out of business, having paid a total of $1.82 million in dividends, versus $456,000 in assessments.