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Minerals associated with gold Primary Gold deposits Secondary Gold Deposits Introduction Metallurgical methods Crushing and Grinding Stamp-milling Feed Water Supply Order of drop of stamps Relative height of drop of stamps Height of discharge Dies and shoes Fine or coarse grinding Coarse grinding Fine grinding Screens High and Low discharge The Ball Mill Classification Ball Mill Operation, Feed Ball Load Pulp Density Balls Speed Size of the Product Jigs and Unit Flotation Cells Shaking Tables Amalgamation Plate Amalgamation Slope of plates and wash water Mercury trap Preparation of plates Dressing the plates Lime in amalgamation Worn-out plates Conditions for successful amalgamation Difficulties in amalgamation Purification of mercury Treatment of Amalgam Retorting Refining of bullion Straking Blanket strakes Treatment of the concentrate Refractory concentrates Leaching Sands leaching Preliminary washing Alkali Wash Cyanide leaching Leaching slimes Agitation of slimes Methods Decantation Counter-current decantation Chemicals and apparatus required Making up solutions Silver nitrate solution Oxalic acid solution Phenolphthalein solution Potassium iodide Object of the test Sodium and Potassium Cyanides Making the test Test for protective alkali Tests for Gold in Zinc Box Effluent Solution Making the test Clarification Filling the zinc boxes Dressing the zinc boxes Conditions for Precipitation Free cyanide in solution Free alkali in solution The zinc shavings Use of lead nitrate Optimal precipitation The Clean-up Acid Treatment Typical flux charges The smelting process Mixing the charge The fusion process Recovery of Free gold Gravity Concentration Principles Types of Concentrators Jigs Pinched Sluices and cones Shaking Tables Centrifuges Treatment of Gold-in-Sulphide Minerals Roasting Amalgamation of roasted concentrate Fine grinding of table concentrates Cyanidation of table concentrates Cyanidation of roasted concentrate Flotation Definition of flotation Operational sequence The tools in flotation Frothing agents Collecting agents pH Regulating agents Depressing agents Activating agents Dispersion agents When to use Flotation in the treatment of Gold Ores Disadvantages of flotation Fineness of grinding Treatment of Pyrite and Pyrrhotite Alkalinity Aeration Lead Salts Water Washing Roasting Treatment of Arsenopyrite and Stibnite Roasting Weathering Presence of Lead Minerals Presence of Copper Minerals Mount Kasi Method Youanmi Method Presence of Calcium Sulphate Presence of Graphite Charcoal Precipitation - CIL and CIP Clayey Gold Ores Housekeeping CYANIDE ANTIDOTE First Aid Cyanide Antidote Mine Valuation Conversion factors Mass Conversion factors Linear Conversion factors Summary of most common conversions Comparison of Screen Sizes APPENDIX 1. CHEMICAL COMPOSITION AND SOME PHYSICAL PROPERTIES OF THE MORE COMMON MINERALS OCCURRING IN GOLD DEPOSITS
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