2023-02-272023-02-271900?-1985https://hdl.handle.net/11124/16634Scale not given.Maps drawn in pencil show sections of mine workings, including Bobtail Tunnel, in the Gregory mining district.36 x 37 cm or smallermine mapsmanuscript mapsengNo Known Copyright: http://rightsstatements.org/vocab/NKC/1.0/.Mines and mineral resources -- Colorado -- Gilpin County -- MapsGregory Mining District (Colo.)StillImage