Big Creek is in eastern Fresno County about 10 miles northeast of the town of Trimmer and 50 miles northeast of Fresno. Superficial placer mining was done here during the early days and sporadic lode mining from the 1890s to around 1915.
A few narrow quartz veins contain free gold and often abundant sulfides. The country rock is granite and schist. A number of contact metamorphic zones in the region contain tungsten and some rare barium minerals, including sanbornite. The chief gold sources were the Contact and Hancock mines.
Bradley, W. W., 1919, Fresno County, Contact mine: California Min. Bur. Rept. 16, pp. 441-443.