Boulder Creek

Mines, Inactive

Commodities and mineralogy

Main commodities Au
Other commodities Ag
Ore minerals gold; silver

Geographic location

Quadrangle map, 1:250,000-scale CY
Quadrangle map, 1:63,360-scale B-5
Latitude 65.281
Longitude -143.017
Nearby scientific data Find additional scientific data near this location
Location and accuracy Boulder Creek is a northwest-flowing tributary of Coal Creek. The coordinates given are for placers at the mouth of the creek, in the NE1/4 of section 3, T. 5 N., R. 22 E., of the Fairbanks Meridian. The creek is about 3 miles long and could have other placer production or exploration along its length. It is location 5 of Cobb (1972 [MF-390]). The location is accurate.

Geologic setting

Geologic description

The bedrock in the Boulder Creek drainage is composed of Cretaceous to Tertiary sedimentary rocks (Dover and Miyaoka, 1988). Placer gold in stream gravels was bright and flaky and had a fineness of 909.5 (National Park Service, 1990). The bench-placer gold is unevenly distributed and tarnished with manganese. Gold was found in the normal-fault contact zone between Tertiary conglomerate on the north and Permian conglomerate with quartz stockwork veins on the south (National Park Service, 1990).
Claims were staked along Boulder Creek as early as 1908, and mining also began about then (National Park Service, 1990; Chapin, 1914). During 1935-36, small-scale drift mining took place along the creek. Placer mines were located near the mouth of the creek, but other locations along the creek may have been mined or prospected. By 1943, the creek had produced 88 troy ounces of gold and 11 troy ounces of silver. By 1951, 334 troy ounces of gold and 42 troy ounces of silver had been removed from the creek (National Park Service, 1990).
Geologic map unit (-143.019389408385, 65.28067056328)
Mineral deposit model Placer Au (Cox and Singer, 1986; model 39a)
Mineral deposit model number 39a
Age of mineralization Tertiary-Quaternary.

Production and reserves

Workings or exploration Mining along the creek began as early as 1908 and continued intermittently until at least 1951. There were both stream and bench placer mines and prospects (National Park Service, 1990).
Indication of production Yes; small
Production notes By 1943, the creek had produced 88 troy ounces of gold and 11 troy ounces of silver. By 1951, 334 troy ounces of gold and 42 troy ounces of silver had been removed from the creek (National Park Service, 1990).

Additional comments

See also Coal Creek (CY006) and Colorado Creek (CY007). This site is within the Yukon-Charley Rivers National Preserve.

References