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
Primary minerals as basalt, rhyolite, andesite and obsidian) and intrusive rocks (such as granite, granodiorite, gabbro and peridotite) contain primary minerals including quartz, feldspar, plagioclase, muscovite, biotite, amphibole, pyroxene and olivine in varying concentrations. For the classical discussions of the origin of primary ores, see the two publications "Ore Deposits" (1903 and 1913). According to W.A. Tarr (1938) the primary mineral deposits are the result of direct magmatic action; he states that the splitting of magmas results in the basic igneous rocks and their accompanying group of accessory minerals formed by the first crystallization in the magma, on the one hand, and