Elevation: 4,747 feet
This old mine is located on a branch of Goose Creek near the top of the Powder River Eagle Creek divide. The following description of the deposit is taken from Lindgren (1901, p. 738-739) and a Department mine-file report compiled in the early 1900's by Charles P. Berkey.
The principal vein, called the Summit lode, was discovered in 1870, and was actively worked during the following years. In 1874 the production was $60,000 from ore containing $16 to the ton. The total production to 1887 is unknown, though probably small, but a mill was then built, and in 1889 production began to increase rapidly. The Mint reports for the 4 years 1889-1892 give $813,000 as the production of the mine. Production ceased in 1897. Total output is estimated at about $1,500,000.
The rocks at the Sanger mine are dark-colored, medium-to-fine-grained mudstones and shales of the Upper Triassic Hurwal Formation. The rocks are pyritic near the veins. The Summit vein strikes nearly due east, dips 30° N. and has been worked to a depth of 400 feet on the dip from several adits and an inclined shaft. An old map dated January 1, 1901 seems to indicate that drifting was done on at least two other veins or fault zones, one paralleling the summit vein and the other crossing it at nearly right angles. The ore shoot in the upper stopes of the Summit vein was 600 feet long, about 15 inches wide and averaged $20 to $25 a ton in gold; below the zone of oxidation the vein widened to 2 to 4 feet and the value dropped to $12 a ton. The gangue is coarse quartz with a little calcite and about 3 percent sulfides, consisting mostly of pyrite with a little sphalerite and galena. Much of the gold was free. In its easterly extension on all levels the vein bends in a broad curve to the south and appears to blend with the strike of the host rocks, losing its characteristic size and value. Toward the west the vein has been offset by faulting, at which point mining ceased. Other veins on the property include the Packwood, Golden Eagle, and Knight. The Big Vein at the head of Fir Gulch may have been the source of the rich placers on Fir Gulch.
Source: Gold and Silver in Oregon, State of Oregon Department of Geology and Mineral Industries, 1968