Colorado (Clear Creek County), Silver Plume special map /
Geological Survey (U.S.)
Chapman, Pearson.
[Washington, D.C.] : The Survey,
1906.
Contour interval 50 feet.
"Surveyed in 1904. Edition of May 1906. Approximate mean declination 1904. Engraved Feb. 1906 by U.S.G.S."
Shows mining activity.
Mines and mineral resources