Blogs

Wet Lead Assay Method

For a number of years I have used for the commercial wet assay of lead generally the ammonium molybdate, and occasionally the ferrocyanide method. These well-known methods need no detailed description here. In the ore-selling and ore-buying establishments of the West, 90%, of all wet lead-assays are made by one or the other, and at least nine-tenths of this proportion

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Silver Sulphide Assaying

There has been considerable discussion of late as to the best assay method for determining the silver-contents of sulphides of silver resulting from the leaching of silver-ores, and also as to the relative merits of the crucible and the scorification-method for the determination of the silver-contents of ores. Owing to the great depression in the silver-market, these are questions of considerable importance,

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Alundum Extraction-Thimble Used in the Copper Assaying

The photograph, Fig. 1, shows the apparatus a little less than half size, consisting of a filtering-flask fitted with rubber stopper through which passes a bent glass tube, and an extraction-thimble fitted with rubber stopper through which passes a glass tube of 0.25-inch bore. Both tubes are connected by a short piece of rubber tubing. A section of a thimble

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Gold Solubility in Nitric Acid of Copper-Bullions-Alloys

In a paper, entitled A Uniform Method for the Assay of Copper Material for Gold and Silver, A. R. Ledoux invited the assayers of this country to contribute to a symposium, in which the results of their assays of given samples of copper-matte and metallic copper would be made comparable. This symposium appeared about one year thereafter; and through it

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Common & Basic Formulas for Mineral Processing Calculations

Table of ContentsMINERAL PROCESSING FORMULASPulp DensitiesCalculation of Circulating Load in a ClassifierCalculation of Classifier EfficiencyScreen EfficiencyMeasure Tonnage by Water Ratio (Pulp Dilution)Pulp Density TablesConcentration and Recovery FormulasTwo-Product FormulasThree-Product FormulasReagent Consumption CalculationsLiquid-Solid Relationships Specific Gravity & VolumeRatio of Concentration by AssayMill Water to Ore Ratio RequirementsResistance of Various Materials to CrushingPulp CalculationsPulp Details by WeightFlotationConditioning or DissolvingPulp ThickeningSimple ClassificationCompound ClassificationReagent ConsumptionInterpretation

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Classification of Minerals

The first step in the identification of a mineral before any chemical tests are made should be the recognition of the physical and optical properties and occurrence of the mineral. The physical properties are discussed below. Color: The color is fairly constant in some minerals but not in all, and commonly the color is due to pigments or impurities in

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Metallurgical Process Flowsheet Development

The data herein has been selected from laboratory notes and incorporates only the usual ore dressing methods in practice for the treatment of common minerals. Necessarily, detailed information regarding location of the mineral deposit, marketing conditions, cost factors and certain specific data concerning the performance of test work in each case is omitted, as such information is held to be

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Method For Measuring Air Hold-Up In Cells

A very unique and simple way of measuring or comparing the amount of air that is working its way up through the pulp of any flotation cell is as follows: A 500 cc or 1000 cc graduated cylinder (smaller size should be used if test is to be made on a laboratory size cell). A stop watch or ordinary watch

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Operating Costs of Gold Processing Plant

Table of ContentsOperating Costs Data on MillGold Mine Operating Manual A small gold mine flowsheet is shown below together with cost data which clearly shows the results that can be ‘obtained when handling a low grade ore by a simple process. There are many commendable features in such a set up and no complicated machines or practices are embodied in

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Hydraulic Dredging for Gold-Bearing Gravels

Repeated failures in attempts to work gold-bearing gravels by means of suction-dredges have created the impression that this method is impracticable. The suction-dredges have failed from three special causes: excessive wear and frequent breakage of pump-shell, runners and liners; inability to dredge compact gravel which would not readily move towards the intake; and, most important of all, closing of the

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Small Mineral Processing Plant Design / Construction

Table of ContentsRequirements for Mineral Processing Plant DesignConstruction of Small Concentrating PlantsPower SupplyElectrical InstallationLightingFeatures Small mines are almost invariably adit rather than shaft mines, and in most instances ore is trammed directly from mine to coarse ore bin at the mill for crushing. Accordingly, most mills are situated adjacent to the portal of the main haulage level. In a few cases,

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Mobile Ore Processing & Beneficiation Plant

One of the most serious problems confronting the mining industry today is how to profitably begin the small scale milling of ores from mines where insufficient ore has been developed to warrant an expensive mill installation, but where a large plant might be needed later. The same question arises in connection with the economical working of numerous small but relatively

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Antimony Smelting

China now leads the world in antimony production, having contributed during recent years something over 60 per cent, of the world’s production. The history of the antimony industry of China dates back to 1897 when the Tai Shing Co. was formed, under contract with the Hunan Bureau of Mines, for the smelting of the ore to crude; and in 1908

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Tungsten Molybdenum System

A complete list of the elements includes 18 that melt above 1,700° C. There does not exist one complete thermal equilibrium diagram for any pair of these 18 elements. Several of these elements have been combined, in relatively small proportions, with metals of lower melting point: e.g. tungsten, molybdenum, and vanadium, in steels, or with nickel and cobalt; but of

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100 to 125 TPD Process Plant Design & Equipment

The 100 to 125 Ton/Day Mill is arranged along the same standard lines as the smaller mills, and a large oversize forced feed crusher is recommended for primary crushing. An intermediate crusher can be installed later if necessary. Changes can be easily made according to your local conditions. Here too, a Selective Mineral Jig may be advisable on gold ores. All

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Small 50 to 75 TPD Process Plant Design & Equipment List

The 50 to 75 Ton per Day process plant is the most practical size for the average milling plant. The 9″ x 16″ Jaw Crusher (forced feed) produces enough crushed ore for the ball mill on one eight hour shift to run the balance of the mill for twenty-four hours. Oversize primary crushers are recommended for most economical results. Note the

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Sphalerite AND Sulphides

As sphalerite is such a common constituent of many types of ore, the present investigation was undertaken to determine what its relations are to the other minerals in the deposits, and also whether these are of any genetic significance. The data presented herewith were obtained from a mineralographic study of about 200 ore specimens from some 43 different localities, represented

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Process Equipment List for a 50 Tons Per Day TPD Flotation Plant

Here is an example process equipment list you’d need to build a small 50 TPD flotation plant to recover metals like copper, lead, zinc or even nickel and most sulphides be froth flotation. Process Plant Equipment Approximate Motor H.P. Crusher 10 x 16 20 Fine Ore Bin Belt Ore Feeder 20″ x 10″ 2 Ball Mill 5′ x 5′ 50

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Gold Ore Chlorination

Experience has shown how difficult it is to obtain information regarding laboratory-tests in connection with the gold ore chlorination process for the extraction of gold from its ores, and I therefore present the following method, somewhat in detail, for the benefit of those who may desire to pursue research work in this field. The ore chosen was a partly-decomposed porphyry,

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Gold Bromination & Gold Chlorination= F(Silver)

Table of ContentsThe Ore-Charge:The Apparatus:The Solvent:Mode of Operating:Results: When dry chlorine gas is made to act in the cold upon finely-divided gold, it converts the latter with evolution of heat into auro-auric chloride, Au2Cl4, a hard, dark-red, hygroscopic salt. Moisture splits this salt into aurous and auric chloride, Au2Cl4 = AuCl + AuCl3 ; treatment with water converts it into

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Allotropy or Allotropism of Gold

It can scarcely be considered a matter of doubt, in the present state of our knowledge, that the existence of, at any rate, two well-marked allotropic modifications of gold can be recognized, namely (a), the ordinary, yellow variety, and (b) the red, brown or purple, non-lustrous, amorphous variety. There are, indeed, not wanting indications that still other allotropic forms may

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Gold Leaching Plant for Sale

FLOWSHEET CY3, COUNTER-CURRENT DECANTATION CYANIDE PLANTThe following estimates are for counter-current decantation cyanide circuits and are based on average grade ore requiring average treatment time. These include precipitation and accessory equipment. The equipment required for a cyanide plant will vary considerably with the value of the ore, the settling rate, the chemical composition of the ore, the hardness, and the

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Base Metal Ore Processing Plant & Equipment (Copper & Lead+)

These 5 following estimates on flotation mills cover standard practice as used on base metal and non-metallic ores where the majority of values are recoverable by flotation, and where there is sufficient freed mineral in the ball mill discharge to warrant recovery by means of process Equipment like either a Unit Flash Flotation Cell, a concentrating table, or a jig,

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Small Gold Ore Processing Plant

These five illustrated flowsheets fully described in the article “Small Gold Ore Processing Plants” follow a natural sequence. These start with a very simple. Flowsheet AA, and then by the addition of the more extensive equipment, it is possible to take care of slight changes in the ore as well as improve recovery. The following tables include the tonnage handled

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