BASTIN, Edson S. & Adolph KNOPF. Three USGS Publications: Silver Enrichment in the San Juan Mountains, Colorado (735-D); Bonanza Ores of the Comstock Lode, Virginia City, Nevada (735-C); The Divide Silver District, Nevada (715-K). Item #6674
8vo, bound together in marbled boards with cloth tape backstrip, typed label on front cover, lacking original wrappers. Washington DC: Government Printing Office, 1921-1922. Front cover damped; good condition overall.