The probable source of placer gold in Rosella (Bear) Creek, located northwest of McDame, are gold-quartz veins found in metasedimentary rocks of the Mississippian to Permian Sylvester Allochthon in the west.
Worked from 1876 to 1915 (sporadically), the creek yielded 12.2 kilograms (432 ounces) of gold (Bulletin 28).