Little Cottonwood Creek (Salt Lake County, Utah) confluence with the Jordan River. The stream provides electrical power generation for Murray City. The first legitimate mining operation in Little Cottonwood Canyon was established in 1865. The ore deposits in Little Cottonwood Canyon yielded principally silver and lead with some copper, gold, and zinc. These ore deposits were formed mainly in shale, limestone, and dolomite. Galena or lead sulfide was the common primary lead mineral of the area. Argentite was found in most of the primary ores and was probably an abundant primary silver mineral. Ore production varied with time because of the nature of the deposits and the
Colorado Mineral Belt about 25 million years. Colorado Mineral Belt The Colorado Mineral Belt (CMB) is an area of ore deposits from the La Plata Mountains in Southwestern Colorado to near the middle of the state at Boulder, Colorado and from which over 25 million troy ounces (778 t) of gold were extracted beginning in 1858. The belt is a "northeast-striking zone defined by: a Proterozoic shear zone system (McCoy, 2001); a suite of Laramide-aged plutons and related ore deposits (Tweto and Sims, 1963); a major gravity low (Isaacson and Smithson, 1976); low-crustal velocities; and high heat flow (Decker et al., 1988)." Mining