The first gold placered in the Bridger district was pulled from Pass Creek in the 1880s. While the production has not been reported, local sources stated that the placers produced only a small amount of gold.
The Pass Creek area is on the boundary of Belt series rocks and sedimentary rocks of Cambrian through Cretaceous age; consisting of quartzites, shales and limestones (Reed 1951).
Prospecting in the Pass Creek area revealed base metal deposits prior to 1901. The September Morn was the most active of the operations that sought to work the deposits. The mine produced ore in 1915, 1925, 1936, 1939 and 1940. However, the mine was only of minor importance to the local economy since an aggregate of less than 100 tons of lead-zinc ore was shipped (Reed 1951).
BOUNDARIES OF THE DISTRICT
Reed (1951) gives the only description of the district with a passing reference to the mines in the Bridger Mountains.
The district as defined by the AMRB (1994) for inventory purposes is shown on Figure 1.
HISTORIES OF SELECTED MINES
aka September Morn
The September Morn mine is located in section 6, T2N, R6E on Pass Creek about 25 miles by road from Belgrade, Montana. The mine was developed by two adits with a combined length of 750 feet on a vein in a dacite dike. The mine extends 300 feet horizontally and 100 feet vertically. Several shallow prospects have exposed a second vein about 800 feet south and 400 feet below the upper adit. The veins contain galena, some sphalerite and traces of molybdenite in a quartz-barite gangue. Although the mine reported shipping ore in 1915, 1925, 1936, 1939 and 1940, no exact tonnage figures are available. It is believed that less than 100 tons of lead-zinc ore were shipped. In 1939 and 1940, 37 tons were shipped that contained 29.3 percent lead and 0.9 ounces of silver per ton (Reed 1951).
Abandoned Mine Reclamation Bureau (AMRB)
1994 Mining districts of Montana. Maps 1:100,000 and Map #94-NRIS-129. Compiled and edited by Joel Chavez. Prepared by Montana State Library Natural Resource Information System (NRIS) for Montana Department of State Lands. Helena
Reed, Glenn C.
1951 "Mines and Mineral Deposits (Except Fuels) Gallatin County, Montana", U.S. Bureau of Mines,
Information Circular #7607