[GOLD EXTRACTION]
Division of methods of treating ores—Scientific extraction indispensable—Superficial knowledge—German and Australian methods compared—Schools of Mines—Antiquity of gold working—Miner’s equipment—Tub, cradle, long tom—How operated—Hydraulic mining—Extensive Australian drifts—Extraction of reef gold—Amalgamation—Crushing appliances—Preference for stampers—The Lemichel syphon—The Griffin mill—The Huntingdon mill—Dodge crusher—Krupp Grusonwerk Ball Mill—Premature plant erecting—Danger of untried processes—Double faulted lode—Automatic ore feeders—Machinery site—Foundations for battery—Weight of stamps—Power and water required for battery—Selection of screen—Fall of tables—Ancient Egyptian gold washing table—Blanket tables—Successful treatment of refractory ore in Australia—Methods vary with ore—Importance of even crushing—Points re crushing—Best form of stamper box—Cleaning plates—Form of scraper—Retorting amalgam—Special difficulties, how to overcome them.
pp. 59-86
[CHAPTER VII]
[GOLD EXTRACTION]
[(SECONDARY PROCESSES AND LIXIVIATION)]
Choosing the plant—-Various ores and their constituents—Amalgamation—Various concentrators—Percussion tables—Frue vanner—Pan concentration—Simultaneous grinding and amalgamating condemned—Watson and Denny pan—Good machines often condemned—Procedure in ore treatment—Duncan pan—Calcining—Rotatory amalgamator—Steaming concentrates—Dry amalgamation—Sulphuric acid and sickened mercury—Amalgamation without overflow—Experiments—Steam as an agent in gold extraction—Lixiviation by chlorine—Various processes—Mount Morgan—Cyanide process.
pp. 87-99