Deer Lodge County Montana Gold Production
The Georgetown district, which includes the Cable mine and placer deposit, is in the northwestern part of Deer Lodge County in the upper drainage basin of Warm Springs Creek about 10 to 15 miles northwest of Anaconda and about 10 miles southeast of Philipsburg. Gold is the most valuable commodity mined in the district, but small amounts of silver and copper are also obtained. Virtually the entire output of lode gold of Deer Lodge County has come from the Georgetown district.
The Cable mine, the most productive in the district, was located in 1866, and a mill to treat the ore was built the following year (Emmons and Calkins, 1913, p. 221-222). The production of the mine to 1872 was worth about $400,000. In 1877, the mine changed ownership and a new mill was built. From 1877 until 1891, more than $2 million (96,760 ounces) in gold was recovered. The ore shoots were supposedly exhausted in 1891, and the mine closed. Under new management the mine was developed to deeper levels; additional ore was found and production was sustained for some time. The Southern Cross mine, another large gold producer in the district, was also located in 1866, but the claim was allowed to lapse. It was relocated in the early 1870's, and ore worth a total of $600,000, mainly in gold, was mined intermittently through 1905 (Emmons and Calkins, 1913, p. 231). The lode mines were moderately active until 1943. Production ceased for the following 6 years, and only a few hundred ounces of gold was produced from 1950 through 1959.
Significant amounts of placer gold were mined in the early years, chiefly from the Cable placer, near the Cable mine, and from the Georgetown placers. The Cable placer was a bonanza deposit. In 1872 and 1873 it yielded $51,000 in gold, and it was worked for many years during which the total returns probably amounted to several hundred thousand dollars (Emmons and Calkins, 1913, p. 264). The Georgetown placers, near Georgetown, produced about $40,000 (1,935 ounces) in gold in 1870. No other figures have been found covering placer production through 1934, and only 96 ounces was recorded from 1935 through 1959.
The total gold output of the district through 1959 was at least 460,000 ounces, most of which was from lode mines.
Faulted and folded sedimentary rocks, mainly of Paleozoic age, are intruded by a small stock and several smaller bodies of granitic rock (Emmons and Calkins, 1913, p. 221). The most productive mines are in the sedimentary rocks near the intrusive contacts, but some deposits are a mile or more from such contacts and some are in the intrusive rock. The deposits include gold-copper replacement deposits of contact-metamorphic origin, gold-bearing replacement veins in sedimentary rocks, and gold-bearing veins in granite (Emmons and Calkins, 1913, p. 221-242). The chief ore minerals are pyrite, pyrrhotite, chalcopyrite, gold, and magnetite in a gangue of quartz, calcite, and garnet. The ore bodies at the Cable mine are large irregular replacement deposits in a large limestone block nearly surrounded by granite. In most of the other mines the ore deposits are chiefly replacement veins in limestone and calcareous shale.