Documents from the G. M. Colvocoresses mining collection. Description: Flowsheet of mill, correspondence, report by Mills, report by Carpenter with assays, report on cyanide plant at mine by Beauchamp, operation accounts, mill record, lease agreement, excerpt titled Re-treating Tailings for Gold at Mercur, extracts from report of Mr. Thomas D. Murphy on cyanide operation July 1895 to June 1896, record of shipments, map of tailing dumps at Bonanza Mine scale 1=50', receipts of transactions and assays, clipping titled Novel Scraper Practice, assays, metallurgical statement cyanide plant. Property Name: Harquahala Mine. Property AKA: Bonanza; Golden Eagle Mine; Harquahala Placers
