_:vb7271021	<http://purl.org/dc/terms/bibliographicCitation>	"1922 November 28, V. C. Heikes, \u201CGold, Silver, Copper, Lead, and Zinc in Arizona\u201D, in Mineral Resources of the United States 1921, part I (Metals), Washington, D.C.: [United States Geological Survey, Department of the Interior]; Government Printing Office, published 1924, \u2192OCLC, page 321:"@en .
_:vb7271021	<http://www.w3.org/1999/02/22-rdf-syntax-ns#value>	"Considerable copper ore, steam-shoveled from Sacramento Hill and piled at Bisbee, was of smelting and milling grade, and some of it was put on the dump for heap leaching."@en .