Quincy Mine  The Quincy Mine is an extensive set of copper mines located near Hancock, Michigan. The mine was owned by the Quincy Mining Company and operated between 1846 and 1945, although some activities continued through the 1970s. The Quincy Mine was known as "Old Reliable," as the Quincy Mine Company paid a dividend to investors every year from 1868 through 1920. The Quincy Mining Company Historic District is a United States National Historic Landmark District; other Quincy Mine properties nearby, including the Quincy Mining Company Stamp Mills, the Quincy Dredge Number Two, and the Quincy Smelter are also historically significant. The Quincy Mine was founded in 1846 by the merger of the Northwest Mining Company and the Portage Mining Company. Due to poor communication between government offices, these two speculative mining companies had purchased the same tracts of land during the mining rush of the early 1840s. The directors met and decided to merge, with significant investment coming from Massachusetts (the town of Quincy, Massachusetts lent the mine its name). While many other copper mines were founded at the same time, the Quincy Mine became the most successful of the 1840s-era mines, and was the country's leading copper-producing mine from 1863 (when it exceeded the production of the Minesota Mine) through 1867 (after which it was exceeded by the Calumet and Hecla). The mine was the first Michigan copper mine to switch from fissure mining to amygdaloid mining, when the recently discovered Pewabic amygdaloid lode was found to cross Quincy property in 1856. High-grade fissure veins contained large, pure masses of copper, but the masses could take days or even months to extract, at high cost. Amygdaloid mining consisted of extracting lower-grade strataform orebodies in the "amygdaloid zones," the upper portions of basalt lava flows. Rock bearing small pockets of copper could be blasted out immediately and processed elsewhere at much lower cost. Amygdaloid mining proved much more productive than fissure mining, and the size and richness of the Pewabic lode in particular allowed the Quincy to produce profits for 53 consecutive years. The Quincy company expanded laterally along the lode by buying out adjacent properties. The company bought the Pewabic mine in 1891, the Mesnard and the Pontiac in 1897, and the Franklin mine in 1908. This helped the mine survive longer than almost all other Keweenaw copper mining companies, except the Calumet and Hecla Mining Company and the Copper Range Company.