Blogs
Base Metal Deposits
Some epithermal veins, worked for gold in the upper, enriched zones, consist mainly of base-metal minerals below the enriched zone. The Smuggler vein at Telluride, Colorado, as shown by Lindgren, is an outstanding example. Its sulphides constitute 2 or 3 per cent of the vein and include principally pyrite, galena, zinc blende, and chalcopyrite accompanied by gold. Its gangue minerals
Gold Ore Deposits
The volcanic source of gold deposits is also most clearly indicated in the Cripple Creek district, Colorado, where the deposits of commercial grade are either within a complex volcanic neck or extend for only short distances into the surrounding rocks. It is true that similar mineralization has taken place for considerable distances from the neck, but only in small, scattered
Hydraulic Sluicing
Supposing that a claim is suitable for hydraulic sluicing, the first thing to do would be to ascertain what is the probable volume and pressure of the water supply. This can be closely approximated by means of an aneroid survey. The facilities for the disposal of the tailings should next be ascertained. As mentioned before, this point is of great
Refining Gold: Remove Zinc by Distillation
Table of ContentsExperimental Zinc DistillationsZinc Distillation Experiments It seems desirable to remove zinc more completely than can be done by acid-treatment, and also to obtain it in a form at once available for precipitation again. I feel safe in saying that from 40 to 50 per cent, of the zinc originally used for precipitation could be thus recovered. Philip Argall
Prospecting Dredge California
In considering the prospective value of dredging ground there are many conditions to be taken into account besides its actual gold content; it is like all other classes of mines in this respect. As a prominent mining engineer recently said: ‘‘Each mine is a law unto itself.” Likewise each dredging scheme must be considered strictly on its own merits before
Gold Dredging
Table of ContentsBucket DredgingHydraulic Dredging The working of gold alluvial deposits by dredging has from all times been a popular form of mining, not only from the simplicity of its operations, but also, in its more primitive stages, from the possibility of carrying it on without large capital, without skilled labour, expensive plant, long terms of preparatory work, or, in fact, any
Ball Mills
Table of ContentsBall Mill Capacity VS Rod Mill CapacityWorking Principle & OperationRod Mill Capacity TableBall VS Rod Mill ConversionTypes of Mill DischargeBall Mill Trunnion and Mill Grate DischargePeripheral Grinding Mill DischargeLoad Capacity of Trunnion BearingsBall Mill & Rod Mill LinersGrinding Mill GearsGrinding Mill DrivesBall Mill Grinding CircuitBall Mill SpecificationsAll-Steel Shells and HeadsTrunnion Bearings of Grinding MillTypes of Mill Feed ChuteSteel Head Ball MillsSteel-Head Rod MillsQuotation
Quicksilver Deposits
Quicksilver deposits are of special interest because they are confined to shallow depths and their origin is comparatively clear. The absence or scarcity of cinnabar and the less common quicksilver minerals in deposits whose features point to deposition at high temperature implies that these minerals are not stable at such temperatures, and the fact that cinnabar is so readily and
Wills’ Mineral Processing Technology
Table of ContentsCLICK HERE to JOIN FREEJOIN now! JOIN 911Metallurgist Discussion Forums to get a chance at winning to get a free (my used) copy of: Wills’ Mineral Processing Technology (Seventh Edition) Barry A. Wills and Tim Napier-Munn An Introduction to the Practical Aspects of Ore Treatment and Mineral Recovery I will select a winner from User Directory on March 1st 2017 and
Arsenic Removal from Water
Table of ContentsArsenic Removal using Lime PrecipitationFerrous & Ferric Solutions Precipitation to Remove ArsenicPrecipitation as a Mixed Calcium Phosphate-ArsenateRemove Arsenic by Precipitation as Barium ArsenatePrecipitation of Titanium (IV) – Arsenic (V) CompoundsArsenic Precipitation of MgNH3AsO4.6H2OPrecipitation as Arsenic SulphideHow to Remove Arsenic from Drinking Water The removal of arsenic from water has been practiced for many years (8-11) but with the recent emphasis on
Amalgamation of Gold & Mercury
Table of ContentsAmalgamation MethodsAmalgamation During GrindingAgitation with MercuryAgitation in Contact with Amalgamated SurfacesThe Size of the Test-PortionThe Laboratory TestAmalgamating-Funnel ApparatusEquipment for Prolonged Amalgamation Any amalgamation test is found to possess most merits and fewest limitations when reduced to the smallest possible dimensions permitting uniform action and certain treatment. A limit is always reached at some point in this reduction in size, where
Assay Laboratory Supplies & Lab Design
Table of ContentsLaboratory Design and Floor PlanHandling Beakers and AcidsFiltering Equipment & SuppliesAssay Furnace Supplies The chemical laboratory in our industrial establishments has remained a factor of minor importance, and, for this reason, not only has progress been permitted to lag, but the methods of analytical work have been carried on along individual traditional lines. Some works-laboratories are equipped with
Classification of Ore Deposits
Table of ContentsLindgren ClassificationDeposits Produced by Mechanical Processes of ConcentrationDeposits Produced by Chemical Processes of ConcentrationIn Bodies of Surface WatersIn Bodies of RocksConcentration of substances contained in the geological body itselfConcentration by Rock Decay and Residual WeatheringConcentration by Ground Water of Deeper CirculationConcentration by Dynamic and Regional MetamorphismConcentration effected by introduction of substances foreign to the rockOrigin Dependent on Igneous
Sieve Analysis Calculations and Graph
Table of ContentsDescription of Sieving Equipment & OperationHow to Plot Grain Size Distribution CurveHow to Plot Semi Log Graph for Sieve AnalysisSieve Analysis Lab Report Discussion & Conclusion The experiments described in this paper were undertaken primarily for the purpose of measuring the quality of work done in screening and sorting in American concentrating-mills for Prof. Richards’ work on Ore-Dressing. For
Geological Mine Maps Sections: Coal Mining
Table of ContentsThe Local MarketsDescription and Discussion of Illustrative Drawings The maps of our large mines are usually prepared with the greatest care; and it is somewhat singular that, in comparison with the great amount of time and money spent in surveying and platting, so little actual use is made of them. Almost the only purpose for which a completed
Metallurgical Chemistry Laboratory Equipment List
The equipment of a laboratory in which students are to be trained for practical work in metallurgical chemistry presents many difficulties not encountered in the fitting up of a commercial or works laboratory. At an industrial plant the chemical work required usually demands the frequent repetition of a comparatively limited number of methods. In a steel-works laboratory, for instance, by
Smelter Laboratory Equipment List
The work of a chemist at a busy smelting-plant differs radically from the work of a student, who takes all possible care to have his analysis exact within hundredths of a per cent., and has plenty of time to devote to the operation. The works- chemist, having the shortest time in which to make his determinations, should have a laboratory
Assay Lead & Copper by Electrolysis Determination
The increasing demand for greater speed and more accuracy, in making daily assays of ores and products from mills treating material containing but very small quantities of lead and copper, has caused the older analytical methods to be supplanted by new ones devised to meet the needs of modern work. For “ control ” work in copper-analyses, I had, previous
Factors Affecting Copper Electrical Conductivity: Effect of Impurities
One of the properties of copper, which has done much to give it its present prominent place among the useful metals, is its electrical conductivity,—a property which has now become the chief criterion of the value of the commercial product. In pursuance of that distinctively American principle that, “ the best is none too good,” metal of the highest conductivity
Effect of Silver on Chlorination & Bromination of Gold
Table of ContentsThe Ore-ChargeThe ApparatusThe SolventsMode of OperatingResults 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
Vanning Buddle Concentrator
I tested an ore, which was peculiarly difficult to treat, on several concentrators then in general use, including the Frue-vanner, the Luhrig table and the Cornish buddle. Owing to the character of the ore it had to be crushed- to a very fine state of division, and the results obtained were far from satisfactory; a large proportion of the values
Refining Zinc Precipitates: Cyanide Leaching of Gold & Silver Extraction
Table of ContentsNature of PrecipitatesExperimental Work Upon AlloysSilverGoldMethods of RefiningRefining by RoastingRefining with AcidSmelting with LeadTavener’s MethodMerrill’s MethodComparison of Costs of Acid Refining & Lead SmeltingRemove Zinc by DistillationGeneral ConclusionsOutline of a Proposed Method of Treatment Attempts to discover, for the cyanide process, a better precipitant than zinc have been unsuccessful. Hydrogen sulphide, sulphurous acid, ferrous sulphate, etc., precipitate gold and silver