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Collection: Directories and Documents > Pamphlets

Empire Mine State Historic Park (PH 8-12)(June 1976) (12 pages)

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MODERNIZATION AND MULES BEFORE WORLD WAR I, MANY NEW AND ADVANCED MINING IMPROVEMENTS WERE MADE HERE AT THE DIRECTION OF BOURN AND STARR. A NEW 500 H.P. ELECTRIC HOIST WAS INSTALLED TO REACH DEEPER INTO THE SHAFT AND HAUL MORE ORE OUT OF THE GRANODIORITE. THE ORE WAS CRUSHED IN THE LARGER CAPACITY 60-STAMP MILL WHERE THE GOLD WAS TRAPPED ON COPPER SHEETS COATED WITH QUICKSILVER OR MERCURY. A CYANIDE PLANT WHERE THE REMAINING GOLD ORE WAS TREATED IN A SOLUTION WITH SODIUM CYANIDE AND THE GOLD PRECIPITATED OUT WITH ZINC COMPLETED THE PROCESS OF REMOVING THE GOLD FROM THE ORE. AN IMPROVED REFINERY CATTACHED TO THE MINE OFFICE BUILDING) PROCESSED THE GOLD AMALGAM AND CYANIDE RESIDUE IN VARIOUS FURNACES TO GET GOLD BULLION. AN EARTH AND ROCK DAM IMPOUNDED THE EMPIRE MINE TAILINGS AND WASTE. THE NEARBY PENNSYLVANIA MINE WAS ACQUIRED ADDING ITS WEALTH TO THE EMPIRE. DESPITE THIS "MODERNIZATION", EVEN TO THE FINAL DAYS OF THE EMPIRE MINE, MULES CONTINUED TO BE THE MAIN SOURCE OF POWER TO HAUL THE ORE AND WASTE ROCK TO THE MAIN SHAFT CTO BE BROUGHT TO THE SURFACE). THESE MULES LIVED IN SNUG, UNDERGROUND MULE BARNS WHERE THEY WOULD STAY UNTIL THEY BECAME TOO OLD TO WORK.