Blogs

How To Use Nitric Acid To Purify Silver

Here is the recipe/method if you want to use Nitric Acid To Purify Silver: First; The Dangers of Nitric Acid Place the silver in a beaker or Pyrex container. Add 3 parts distilled water to 1 part nitric acid. Place on stove or hot plate and simmer until all of the metals are gone. Take un-iodized table salt and drop into

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Recover Gold/Silver in Jewelry/Electronics eScrap by Aqua Regia

The Dangers Of Aqua Regia:  Aqua regia cannot be boiled or simmered in the house or where it is not well ventilated. This can cause serious illness or KILL YOU! Use a vent hood with an exhaust fan or simmer in the open. Hydrochloric acid is very dangerous. It CAN BURN TO THE BONE and is extremely painful. In most cases,

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Methods to Estimate AG/SAG Mill Power Requirements

A linkedin.com group was recently discussing this by asking:  I’ve tried to estimate AG/SAG Mill power requirements using several different methods: (1) Using the results of SMC data (2) Using SAG Power Index (SPI) data (3) Using the 1989 Barratt method updated on Alex Doll’s Web site (February 16, 2015) (3) Using Don Burgess’ method (11th Mill Operators Conference 2012) They

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Online Geology Course

Here is a “how” series on ore mineral deposit formation acting as a FREE Online Exploration Geology Courses to help non-technical people understand ore deposits, how they form, how they are explode for, how they are evaluated and mined and how the metals and minerals are extracted from the ore. The talks highlights some of the features of the main ore deposit types

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Understand Fluorine in Copper Concentrate (F in Cu Conc)

A copper flotation concentrate is over limit on Fluorine (F) content and Contamination.  When assaying and plotting Copper (Cu) from times concentrates and the related fluorine and Magnesium Oxide (MgO) assays in various ways as shown below; one can see the obvious relationships. In the case, reducing Fluorine content and contamination of the copper conc with likely by using regrinds

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Ball Mill Motor Power Draw Sizing and Design Formula

The following equation is used to determine the power that wet grinding overflow ball mills should draw. For mills larger than 3.3 meters (10 feet) diameter inside liners, the top size of the balls used affects the power drawn by the mill. This is called the ball size factor S.  Rod and Ball Mills by C.A. Rowland and D.M.

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Rod Mill Design & Power Draw

Table of ContentsUsing the Bond Operating Work Index for Circuit Performance AssessmentBasics of Rod Mill Power Draw The following equation is used to determine the power that a rod mill should draw. The Bottom Table lists many of the common size rod mills giving speed, loading and power data. The rod mill motor power is in horsepower at the mill pinion-shaft.  For

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Gold Rocker Box

Table of ContentsGold CradleGold Rocker Box Design One of the first devices used after the gold pan was the gold rocker box. The rocker allowed small operators to increase the amount of gravel handled in a shift, with a minimum investment in equipment. Rockers vary in size, shape, and general construction, depending upon available construction materials, size of gold recovered,

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Mafic Layered Intrusions -Chromite and Platinum PGE Deposits

Another major groups of deposits in the mafic layered complexes are platinum group elements and chrome deposits but unlike copper nickel massive sulfides they don’t form as puddles on the floor of the intrusions they form in discrete layers well up in the magma chamber. The PGE’s that’s platinum palladium, rhodium with less amounts of osmium, ruthenium and iridium are

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Igneous Rocks Formations

Table of ContentsCharacteristics of Igneous RocksClasses of Igneous Rocks Igneous rocks; those that are formed from molten magma are broadly classified according to their chemical composition using silica, potassium, sodium, calcium, iron and magnesium as the key indicators. Magma is rich in silica, sodium and potassium generally form pale colored feldspar when they crystallize and are termed felsic. They are

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Mafic Layered Intrusions -Copper/Nickel Massive Sulfide

Mafic Layered Intrusions and complexes including copper nickel massive sulfide, chrome and platinum group elements or PGE deposits.  This course on massive sulphide deposits includes copper and nickel exploration methods, nickel sulphide inclusions exploring for copper and nickel sulphide minerals. In the introductory Exploration Geology Course I mentioned felsic, mafic and ultramafic rocks but before I launch into talking about

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Rate of Gold Recovery by Size of Particle

Here is a review of various gold recovery machines/methods and the gold particle size they are best suited to recover.  Compare Jig, shaker tables, dry washer, sluice box, spirals, bowl concentrators, falcon, Knelson and leaching. The size distribution of the raw material will also determine if classification of the ore is necessary for better recovery. The processing capacity of the

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Kimberlite Deposits and Geology Formation of Diamonds

The geology of Diamonds consist of crystalline carbon although a significant proportion of diamonds are derived from placid deposits i.e. hosted in sediments, placid’s are secondary deposits and all diamonds were at one time or another hosted by kimberlite igneous rocks. The name Kimberlite comes from the town of Kimberley which grew up around the prolific diamond mines in northern

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Mill Critical Speed Calculation

Table of ContentsEffect of Mill Speed on the Energy InputEffect of Liner Profile on the TrajectoryEffect of Friction of the Wall on the Charge Profile Effect of Mill Speed on the Energy Input In this experiment the overall motion of the assembly of 62 balls of two different sizes was studied. The mill was rotated at 50, 62, 75 and

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Estimate Mill Steel OR Rock Charge Volume

This is a 2nd Method for estimation or measuring the steel charge volume inside a mill. If dealing with a full SAG/AG mill, this will give you the rock load%.  If you can count liners, you’ll have your answer. The 1st method uses similar parameters. Find more at https://sagmilling.com/tools_millfilling Effect of Mill Filling on the Energy Input The effect of mill filling on

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Calculate Ball Mill Grinding Capacity

The sizing of ball mills and ball milling circuits from laboratory grinding tests is largely a question of applying empirical equations or factors based on accumulated experience. Different manufacturers use different methods, and it is difficult to check the validity of the sizing estimates when estimates from different sources are widely divergent. It is especially difficult to teach mill sizing

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Cyanide Leaching and Decomposition of Pyrrhotite

Research on cyanidation methods brought considerable discussion on the reactions involved in the leaching and decomposition of pyrrhotite in cyanide solutions.  Pyrrhotite has one loosely held sulphur atom which readily reacts with cyanide to form thiocyanate: Fe5S6 + NaCN = NaCNS + 5 FeS The ferrous sulphide oxidizes rapidly to the sulphate which reacts with cyanide to form ferrocyanide: FeS + 2

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Calculate a Classifier and Screen’s Efficiency

Classifier and screen performance formula: Classification efficiency is generally defined as the weight ratio of classified material in the sized overflow product to the total amount of classifiable material in the classifier feed, expressed as a percentage. For two-product separations, the general form used is: Cytec [/fusion_builder_column][/fusion_builder_row][/fusion_builder_container]

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Calculation of Top Grinding Media Size -Ball Sizing

The majority of grinding balls are forged carbon or alloy steels. Generally, they are spherical, but other shapes have been used. The choice of the top (or recharge) ball size can be made using empirical equations developed by Bond (1958) or Azzaroni (1984) or by using special batch-grinding tests interpreted in the content of population balance models (Lo and Herbst

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3 Product Recovery Calculation & Formula

In this metallurgical (material/MatBal balance) involving 2 concentrates or 3 products, we have this example: It is decided to take a copper tail (zinc feed) sample in order to provide a check on the results calculated in the previous example. The sample (CT) assayed 0.55% Cu (c5) and 20.9% Zn (z5), respectively. The check weights of the copper and zinc

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3 Product Recovery Formula: Material Balancing & Metallurgical Accounting

Frequently, a concentrator will mill a complex ore requiring the production of two separate concentrates, each of which is enriched in a different metal or valuable mineral, plus a final tailing acceptably low in both constituents. Formulas have been developed which use the feed tonnage and assays of the two recovered values to obtain the ratios of concentration, the weights

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