Mineral Processing Engineering

Placer Gold Analyzer XRF

placer gold xrf analyzer analysis method

HiGrade DPI is a novel analysis method for placer gold that relies on the distinct color of gold. Analyse surface or drill samples from a placer claim . Determine the gold grade and properties. Produce instant printable reports for each sampling location of the claim.


The pan concentrate is placed on a specially designed sample holder from where a high resolution image is created with an optical scanner. Then the automatic HiGrade DPI particle analyzer detects gold particles based on their golden color and calculates the gold grade of the sample. The automatically generated report includes unique statistics on the particle size distribution and particle shape. The analysis takes less than 5 min, requires no consumables and is non-destructive.



HiGrade offers a comprehensive tool kit for industrial and scientific applications, including dedicated prospectors, mineral laboratories, exploration firms and placer operations.

Exploration of Alluvial/Eluvial Gold Deposits

The topic of this short information is the exploration of deposits of not consolidated (loose) gold bearing material with free

Merrill Crowe Laboratory Testing Procedure

Efficient Merrill Crowe precipitation of gold and silver is dependent upon the proper control of certain physical and chemical properties of the solution. The most important of these properties are listed below:

Suspended solids: such as ore slime and precipitates of calcium carbonate, with hydrates of aluminum, magnesium and iron, present in the pregnant solution before clarification. These combined solids should be completely removed by efficient clarification.

Suspended precipitates: as above defined, which may continue to form in the solution after clarification. This formation occurs slowly and is almost completely prevented by clarifying and precipitating simultaneously.

Scale forming compounds: mainly the carbonates and sulphates of lime.

Oxygen and carbon dioxide gases dissolved in the solution: these prevent efficient precipitation of the precious metals. The solution must be oxygen free.

Cyanide strength: a small amount of free cyanide is necessary to catalyze the zinc:gold reaction but as little as 50 ppm of free cyanide should normally be sufficient. This is only the case if the solution is relatively free from base metals like copper.

Alkalinity: normally the solution pH is already above 10 as a result of leaching. pH should be maintained at this minimum level.

Copper: excess copper will prevent the zinc:gold reaction as it preferentially precipitates

How to Recover Molybdenum in Oxidized Ore

A study of some variables affecting the recovery of molybdenum from oxidized molybdenum minerals was made. The effects of variations in contact time, temperature, pulp density, particle size, and solvent concentration on the recovery of molybdenum using acid and alkaline solvents were investigated. Chemical analyses, screen analyses and microscopic examinations were made and the presence of important elements determined.

Description of the Ore

Geologically, this ore occurs in the bottom of the Chadron formation sandstone at the disconformity between the Chadron formation and the Pierre shale. Hand samples of the mineral ilsemannite have also been recovered from this deposit. The rock is composed predominantly of silica sand. The bonding material contains the molybdenum minerals and the iron minerals hydrated and otherwise.

The ore sample was stage crushed through 6 mesh and mixed by recombining splits from a Jones riffle. Upon further sampling and analysis it developed that we could cut reproducible (± 0.01% M0O3) samples at 100 gms wt from our minus 6 mesh aggregate.

Experimental Work.

The first sequence of tests were run to determine the effect of roasting on molybdenum extraction. A series of samples was roasted for one hour at temperatures of 100°, 200°, 300° and 400° C

Power Scale-Up for Agitating Slurries

An interesting problem with which the senior author has been concerned with is the scale-up of power requirements for slurry agitators operating in the laminar region with pseudo-plastic materials. Pulps of shaly ores, after various chemical reactions in aqueous leaching systems, are often difficult to settle and filter if agitation is violent. In these cases agitation must be at a minimum, yet prevent tling such as in copper uranium ores. This mild agitation is on the laminar region.

The starting point of this investigation is the known relationships for agitating Newtonian fluids. The Reynolds number is a measure of similitude in agitation and is derived from the ratio of the internal reaction per unit volume of fluid (V²D) and a viscous force present per unit of volume (µV/D²).

For flow through pipes, this is:

RE = P V²/D/µ V/D² = D V P/µ

where: RE = Reynolds numbers
D = diam. of pipe
V = velocity
p = specific gravity
µ = viscosity

all in consistent units.

For agitation, velocity is the speed at the tip of the impeller. If N is agitator revolutions per second, then: π D N = V. Since π is a constant, the Reynolds number of agitation becomes:

RE = N D² p/µ

Tertiary Zeolite Ore Mineral Distribution in Size Fractions

Zeolite ores and protores occur in extensive deposits in the western United States. A recent paper describes the general geology and mineralogy of these deposits and their geographical distribution. The zeolites are alkali- and silica-rich varieties of mordenite, erionite, chabazite, phillipsite, ferrierite, and clinoptilolite.

The Tertiary zeolite ores consist of one or more zeolites (mordenite, erionite, chabazite, phillipsite, ferrierite, clinoptilolite) formed as alteration products of pyroclastics. In addition to unaltered volcanic glass the gangue minerals include quartz, cristobalite, tridymite, opal, feldspar, montmorillonite, hornblende, calcite, gypsum, thenardite, iron oxides, and in some cases one or two other zeolites. Removal of the silica minerals and glass is the main problem in ore beneficiation.

Mineralogical analysis of size fractions obtained on zeolite ore samples dispersed with minimal grinding provides a quantitative determination of the constituents, reveals the microtexture, and gives the size distribution of the single crystals and various types of aggregates and particles. These data are useful for beneficiation as they aid in the choice of the initial method of disaggregation and give the size ranges in which the zeolite and gangue minerals concentrate.

The bulk mineral compositions, as determined by analysis of the size fractions; abbreviations used are mordenite (MO), clinoptilolite (CL), erionite (ER),

Mine Drainage Control and Treatment

Standards vary from state to state for reasons which I find impossible to explain. For example, Pennsylvania has set an iron limit of 7 mg/liter (7 ppm) on the discharge from a treatment plant. West Virginia, on the other hand, has adopted 10 mg/liter (10 ppm) in the receiving stream as a satisfactory iron level, thus giving proper credit for the dilution effect of the stream. As you all know, public hearings are currently being held in all fifty states, attempting to develop stream standards which will be satisfactory to both the states and the Federal Water Pollution Control Administration. So, we still are aiming at a moving target.

Now, let’s consider the fate of the ferrous iron and the acid in the water as it moves—miles, in many cases—from its point of formation to its point of discharge. As all of you know, substantial amounts of limestone or calcium carbonate are associated with coal deposits.

The first reaction (Equation 1)—which occurs rapidly—is the reaction of the acid with, say, limestone. Bicarbonate ion is formed and acid in the mine water is neutralized.

After, or simultaneously with neutralization of the acid, another important reaction begins. You will remember that I stated that ferrous,

Use LIX-64 Extractant for Copper Pilot Plant Data

Design parameters for scale-up to commercial plants are presented and discussed along with a revised capital cost estimate. The future pilot program is discussed, including minor design changes and the effect of entrained organic on dump leaching efficiency.

Description of The Liquid Ion Exchange Process

In the extraction section, a water-immiscible organic solvent (normally kerosene) containing an organic extractant is contacted with an aqueous solution containing the metal to be extracted. The two phases are then allowed to separate. Interstage pumping of both organic and aqueous is accomplished by employing the mixer impeller as a pump. A variable number of mixer-settler stages and flowrates may be used to achieve the desired recovery and concentration of the metal from the feed solution. After removal of the metal values, the aqueous solution leaving the extraction section is referred to as the raffinate.

The organic phase containing the metal values (referred to as the loaded organic) is then transferred to the stripping section, where the metal values are transferred from the organic phase to an aqueous solution for subsequent treatment, and the stripped organic recycled to the extraction section.

Chemistry of LIX-64

While the exact chemical structure of LIX-64 cannot be disclosed at

How to Improve Minerals Beneficiation Plant Performance

Rising demand, artificial market conditions, increased overseas competition, and a fluctuating international situation have brought ever increasing pressures to bear on the nonferrous metals industries, and particularly in the United States. Although capacity is being expanded by the construction of new plants and the development of new ore deposits, increasing attention is being focused on the possibilities of improving the performance of the existing installations and of getting the most out of the new equipment now installed. At first sight the task appears formidable.

It requires only a cursory glance at the process for mining, concentrating and extracting the values from metal ores to recognize that more careful scheduling of the mining operation will result in reduced variation in the quality of ores presented to the mill, leading to smaller variations in the particle size distribution of the feed to the flotation cells and more consistent recovery of the values at the desired grade.

Control Techniques

Before discussing in detail the means by which the performance of a mineral ore concentration plant can be improved, a brief review of the control techniques available may be helpful.

A typical example of a single loop feed back control system is a grinding circuit. Here

Designing a Mill for Maintenance

Its purpose is to highlight the things that have been accomplished by the mill designers to lighten the load for the maintenance superintendent and to reduce the overall costs for the plant operator. The complexity of plant design, the civil and structural engineering problems encountered when the satisfactory maintenance layout is accomplished are appreciated, and the writer is fully aware of the complexities of these problems. However, it is not the purpose of this particular paper to dwell upon these problems, nor to emphasize or de-emphasize the problems of the civil, mechanical and electrical engineers. It is simply that the paper will attempt to review what these people have accomplished in spite of the many technical problems.

Maintenance Areas

The old-timer repaired most pieces of equipment in place in the area available, and if additional space was needed it was arranged to transport the part or the piece of equipment to some sort of a central shop. Except for the most sophisticated plant, there was no allowance for a shop or a maintenance area as such in any plant. In addition, consideration was not given to laydown and maintenance areas adjacent to the larger pieces of equipment. There were a

Heap Leaching Copper Ore

Ranchers began its evaluation of the Bluebird Mine in late 1963. The property which included some 400 acres, adjoined one of the country’s leading producers – Inspiration Consolidated Copper Company. Such proximity led many to equate availability with undesirability. However, a relatively short period of exploration and metallurgical evaluation and a simultaneous assessment of other environmental elements led Ranchers to acquire the property and to expand its operation. The objective steady, continuous production, at a substantial level. The property was to become one of the first medium-sized copper mining operations to rely solely upon heap leaching as a means of production.


Ranchers Exploration and Development Corporation obtained a 90-day option on the Bluebird property from Stovall Copper Company in January 1964. A 6,000 foot drilling program was initiated, and it was soon evident that the deposit consisted entirely of oxide ore. The economics of both vat and heap leaching were studied. Costs relating to mining, crushing, ore, waste and tailings handling, leaching, and recovery were examined closely. Leaching factors which received the most attention were acid consumption and costs and labor, power, and water costs. Since precipitation using iron was believed most feasible at the time, iron consumption and

BUY Laboratory & Small Plant Process Equipment

We have all the laboratory and plant equipment you need to test or build/operate your plant.

ENTER our Mining Equipment' Store

We Sell EQUIPMENT for all types of Mineral Treatment PROCESSES and Laboratory Testing needs


View the Services we Provide

911Metallurgist Mineral Processing & Process Development Laboratory

We have a metallurgical test for every possible mineral type and treatment.


We can IMPROVE ALL PLANTS / Mineral Processing Engineering & LABORATORY Ore Testing

911Metallurgy Engineering

Contact us for process engineering, metallurgical investigations, plant optimization, plant troubleshooting, needs. WE “FIX” METALLURGY.

I Need Consulting Engineering Help
I Need Ore Laboratory Testing