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Panning for Gold

Table of ContentsTELLURIDES IN GOLD ORESWhere to look for Native GoldPANNING FOR GOLD IN AUSTRALIAGold Panning in VictoriaPanning for Gold in New South WalesPanning for Gold in QueenslandPanning for Gold in West AustraliaPanning for Gold in New ZealandGold Panning in New GuineaGold Panning in ASIAPanning for Gold in IndiaPanning for Gold in SOUTH AFRICAGold Panning in LydenbergGold Panning in De Kaap

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Characteristics of Common Minerals

Table of ContentsALUMINIUMBauxiteCryoliteANTIMONYSulphide of Antimony (grey antimony)The ore from which the antimony is extracted:Fuses in the flame of a candleBISMUTHCHROMIUMTYPES OF COBALT MINERALSTin White CobaltEarthy OxideCobalt BloomTYPES OF COPPER MINERALSNative CopperCopper Glance (vitreous copper ore)Copper Pyrites (chalcopyrite)Grey Copper (tetrahedrite)Red Copper Ore (ruby copper)Black Oxide of CopperSilicate of CopperMalachite (green carbonate of copper) As mentioned before, in the last chapter, any

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How do Prospectors Find Gold

In prospecting a country for Prospecting for valuable minerals wealth, it is most important to search very systematically and carefully among the sands and rocks of river beds, in dry creeks, and at the bottom of valleys, as well as on the sea-shore. Not only does the action of running water and glaciers grind down masses and particles, and, through

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Classification of Rocks and Minerals

Table of ContentsIGNEOUSMETAMORPHICAQUEOUS The following are the various divisions under which rocks may be classified: IGNEOUS Rocks which have been subjected to heat. Volcanic (those that have been cooled at or near the surface) :— Trachyte (rough, greyish in colour, and light in weight). Basalt (blackish or brown, heavier and with fewer holes in it than trachyte). Phonolite, Andesite (of

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Process used to Identify Minerals

Table of ContentsMohs hardness scale definitionTesting for HardnessIdentifying Minerals by WeightHow to Identify Minerals by MagnetismFundamental forms of crystalsVarious names are given to the crystal mineral systemsCharacteristics of MineralsColor and streakLusterHardness In the process of discovering the nature of a rock and Identifying Minerals, the mineralogist may derive the necessary information by a careful study of its external appearance and characteristics; the

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Blowpipe Assaying

Table of ContentsApparatus required consists of the followingBlowpipe AssayHow to make a blowpipe for temporary use in mineralogical analysis How to make and use a blowpipe to test and perform a metal analysis for the presence of various minerals by evaluating the nature of the flames. Methods of testing in an open tube and a tube closed at one end.—On charcoal

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Zinc Cyanide Plating Process

Table of ContentsPREPARATION OF SOLUTIONSANALYSIS OF CYANIDE SOLUTIONSPRINCIPLESMETHODS OF ANALYSISPreparation of the SampleTotal ZincTotal CyanideTotal AlkaliCALCULATION OF THE RESULTSTotal ZincTotal CyanideTotal HydroxideOPERATION OF SOLUTIONSComposition and ConcentrationCurrent DensityTemperatureConditions Recommended1 Composition.Current density: In order to secure definite information regarding the best conditions of operation of plating solutions, it is necessary first to obtain reliable methods for preparing and analyzing solutions of any given

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Treatment of Mixed Sulfide Oxide Ores of Copper

Table of ContentsSULFURIC ACID AS A SOLVENTTREATMENT OF OXIDIZED COPPER BY AGITATIONSULFUR DIOXIDE AND AMMONIA AS SOLVENTSIRON SALTS AS SOLVENTSOTHER SOLVENTS FOR OXIDIZED COPPERCONTROL OF TEMPERATURE DURING SULFATIONTHE PRECIPITANTELECTROLYSISSULFUR-DIOXIDE PRECIPITATIONHYDROGEN SULFIDE AS PRECIPITANTPRECIPITATION BY HEAT ALONEOTHER PRECIPITANTSMECHANICAL HANDLING OF ORE AND SOLUTIONADVANTAGE OF SULFIDIZING FLOTATION Many of our largest copper deposits contain both sulfide and oxidized copper minerals. The large

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The Mathematics of Gravity Concentration

Table of ContentsGRAVITY CONCENTRATIONFALL OF A BODY IN STILL WATERFALL OF A BODY IN STILL WATER DURING A CONSIDERABLE TIME INTERVALFALL OF A BODY IN STILL WATER DURING A VERY SHORT TIME INTERVALBEHAVIOR OF A SOLID BODY IN AN ASCENDING CURRENT OF WATERA. In a State of SuspensionB. In a State of MotionMOTION OF A SOLID BODY IN A DESCENDING

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Table of Apparent Geological Dips Calculated Chart

Table of ContentsCalculated Table of Apparent Dips in Vertical Section Geological Dip ChartNew Life-saving Aid The form of dip chart here presented for the use of the profession was devised by the author when he was confronted with a particularly heavy job of geological section making and did not have any of the usual tables or charts at hand. This

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Cyanide Poisoning Antidote

Table of ContentsPreparation of AntidoteAdministration of the AntidoteIncite VomitingTreatment in ease of Cyanide Poisoning In 1910, the Committee of the Chemical, Metallurgical and Mining Society of South Africa, appointed to investigate cyanide poisoning, recommend as an antidote to Cyanide Poisoning the following: Thirty cc of a 23 per cent, solution of ferrous sulphate. Thirty cc of a 5 per cent, solution

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Agitated Cyanide Gold Leaching Test

Table of ContentsConcentration TestsLead SaltsTest for Repeated Use of the Same SolutionUse of Working Plant SolutionLarger Agitation Charges In the old days laboratory tests were usually made by mechanically shaking up in a bottle for a given time a charge of ore and cyanide solution. The most generally convenient device for this purpose is a wheel, to which are attached

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Unconfined Compressive Strength Test of Rock

This test method specifies the apparatus, instrumentation, and procedures for determining unconfined compressive strength of intact rock core specimens. This procedure is identical to ASTM D 2938 except that the cores are tested after cutting without grinding, and neoprene caps are used on the specimen ends. Unconfined Compressive Strength Test Procedure Check the ability of the spherical seat to rotate freely in its

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Determine the Proper Grind Size for Gold Ore

Without mineralogy, estimating the optimum Grind Size for Gold Ore Sample is most conveniently made by Laboratory Testing and the agitation leaching method, and it will be necessary to make up 3 or 4 bottle charges in order to have enough ore* for the subsequent screen analysis. Take an average sample of the ore and grind on the bucking table to

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Calculating Cyanide Consumption

Table of ContentsHigh Cyanide ConsumptionConsumption of Cyanide – Feldtman’s Test Computing Cyanide Consumption of a laboratory leach test may be done as in the following example: Ore taken, 250 grams. Ratio of solution to ore, 3:1 = 750 cc: 250 grams. Cyanide strength, 0.3% KCN. Or when working on the metric system, Ore taken 200 grams, ratio of solution to ore

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How to Test Ore or Rock for Gold Content

In all experiments aimed at testing the gold content of rocks or “ore”, you should ask yourself whether the conditions of his test differ in any vital particular from those that would obtain on a commercial scale; if so, there is no guarantee that his results would be borne out in a working plant. Small scale experiments are very valuable if

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Cleaning & Melting Gold Precipitate

Table of ContentsFlux RecipePreparation of The Charge for Melting ChargingPouringSamplingThe Tavener Process With zinc shaving precipitation the usual method of cleanup is to shut off the flow of solution and starting at the head compartment of a box to wash the shavings gently in the solution avoiding any action that would tend to break up the attenuated threads into short pieces. The

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Tavener Process – Smelting Gold with Lead & Flux

The Tavener process of melting the gold precipitate in a reverberatory furnace with litharge, thus forming a lead bullion which was afterward cupelled in the usual way. He deals with the zinc shorts by the same method but recommends that the two products be partially dried and separately fluxed. For the precipitate he uses the following mixtures: Product……………………………………100 parts by

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Gold Precipitation

Table of ContentsGold Precipitation with ZincElectrolytic Gold PrecipitationAluminium PrecipitationSodium Sulphide PrecipitationCharcoal Precipitation Whatever method of gold precipitation be used it is of great importance that the solution should be absolutely clear and free from suspended matter, and in practice it is almost impossible to obtain solution from slime treatment, either by decantation or by means of the various types of

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Precipitation of Gold on Carbon – Charcoal

Park states that this method is in use in many plants in Victoria for precipitating gold from cyanide solutions the procedure being to pass the solution through barrels packed with finely broken carbon/charcoal, which is afterward burned, and the ash melted down with fluxes. He does not consider it suitable for large tonnages of solution. H. R. Edmands describes a

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Gold Recovery by Aluminium Precipitation

Table of ContentsHow the method of precipitating gold with aluminum worksHamilton’s Process of Gold PrecipitationAdvantages of Aluminium as a Gold Precipitant The use of aluminium as a precipitant for gold out of cyanide solutions was patented by Moldenhauer but he does not appear to have made any practical use of the process. H. F. Julian experimented with it, in the same year,

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Recovery of Gold by Precipitation with Zinc

Table of ContentsWhite PrecipitateWhat is the role of Oxygen in Gold PrecipitationThe Crowe Vacuum ProcessHow Lead increases Gold Precipitation by ZincHow Copper affects gold precipitationMethod of Working When Using Zinc ShavingsCapacity of Zinc BoxesZinc Dust PrecipitationAdvantages of method of precipitating gold with zinc dust The recovery of the precious metals like gold and silver from the cyanide solution is almost universally

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Electrolytic Precipitation of Gold

Table of ContentsWeak SolutionStrong SolutionRegeneration of Cyanide in Electrolytic Precipitation This was introduced on a commercial scale as an adjunct to the cyanide process on the Rand for precipitating the weak and low-grade solutions resulting from the treatment of slime by decantation, and was known as the Siemens Halske process. The anodes were of sheet iron enclosed in burlap to

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