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By A. E. J. Gallagher

There are many influences which have a bearing on the economics of industrial minerals production. The purpose of this paper is to discuss briefly three factors which have economic significance in the production of these mineral commodities. The three items of discussion include 1) the nature and relative value of the industrial minerals group, 2) project planning, and 3) market analyses. General aspects of these factors are familiar to most of us. However, an attempt will be made to give some current details regarding each. Also, in reality, project planning and market studies are usually so closely associated that they will be discussed jointly, rather than separately. This will be done by way of examples which show how these two activities actually evolved for two industrial minerals projects.

Jan 1, 1984

By Sheldon P. Wimpfen

Under the Wilderness Act of 1964 and the accompanying House Conference Report, the Geological Survey and Bureau of Mines are charged with the responsibility of making recurring mineral studies of wilderness and wilderness candidate areas in national forests within and proposed for the National Wilderness Preservation System. The Wilderness Act, a major shift from the multiple-use concept of national forests, identified for the first time the value of mineral resource information in decisions for single-use designation of public lands. This concept was further realized when the Secretary of the Interior in May 1974 recommended that mineral studies be made prior to wilderness recommendations for five large Interior-managed game ranges and the Glacier Bay National Monument aggregating 7.8 million acres. Presently, our studies have been completed on 126 wilderness and proposed wilderness areas totaling 15.4 million acres in the national forests. In 1973, 1 year in advance of the act's 10-year review deadline, we completed the 34 primitive areas, originally the only potential additions considered by the 1964 Act.

Jan 1, 1975

By H. Verakis, M. J. Sapko

The Pittsburgh Research Laboratory (PRL)1 of the National Institute for Occupational Safety and Health (NIOSH) in collaboration with the Mine Safety and Health Administration (MSHA) Technical Support Center has devised a prototype hand-held instrument which can provide a direct assessment of the potential explosibility of a coal and rock dust mixture. Current Federal regulations require that rock dust be applied in all underground areas of a coal mine to mitigate the propagation of a coal dust explosion. To determine compliance with the Federal regulation, mine inspectors collect dust samples from sections of underground coal mines for an MSHA laboratory analysis of incombustible content. However, the laboratory analysis may not be completed for more than a week or two, during which time the mine area from which samples are taken may be inadequately protected. The operation of the Coal Dust Explosibility Meter (CDEM) is based on the difference in optical reflectance between light rock dust and dark coal dust. For a given coal volatility, the optical reflectance of such mixtures is relatively constant at the limit of explosibility, independent of the coal dust particle size. The CDEM is not intended to replace the current MSHA laboratory analysis of coal mine dust samples for incombustible content, but to serve as a supplemental device for enhancing mine safety through improved rock dusting practices.

Jan 1, 2006

By David J. Gurtler

In early 1988, Chino Mines Co. began using a system of economic splits for all materials encountered in mining. All mined material is evaluated as mill ore, solvent extraction electrowinning plant feed, and non-ore material, to determine its disposition. Results thus far indicate a significant increase in financial returns on material mined compared with the copper cutoff grade previously in use. Chino Mines is a partnership between Phelps Dodge Corp. (two-thirds ownership) and Mitsubishi Corp. (one-third ownership). The company produces copper and byproduct metals from the historic Santa Rita del Cobre mining district in southwestern New Mexico. The history of copper production in the district began with the use of surface native copper by native Americans before 1800. Spanish soldiers from Mexico later became aware of this district and mining began in 1801. The district was worked intermittently until 1909 when the Chino Copper Co. was formed, with Daniel C. Jackling as vice president and managing director. Concentrator operations were started in 1911. Kennecott purchased the company in 1933 and built a smelter in 1939. Chino Mines Co. was formed in 1980 when Mitsubishi purchased one-third of Kennecott's holding at the property.

Jan 1, 1990

By James A. Doolittle

In the underground type of mining operation, the finer portion of the waste material commonly is pumped as a hydraulic slurry to a tailings disposal pond. (1)* The tailings slurry is deposited via a pipe manifold system located around the perimeter of the pond. This method of deposition produces zoning because the coarser material tends to settle out immediately while the finer particles tend to remain in suspension and are deposited progressively nearer the center of the pond. The manifold system must be raised periodically as the pond fills with the tailings material. Over a period of time, this procedure will produce a zoned embankment known as a tailings dam. A typical pond and dam are shown in Figure 1. In plan view, the dimensions of tailings dams can be on the order of miles, with the height of the dam reaching 100 to 200 feet. Due to such factors as inadequate compaction, inherently low strength of the tailings material, and the possibility of high phreatic surface, many dams at some point become unstable, i.e., the factor of safety against a slope failure approaches 1.0. Remedial measures are required to improve the safety factor in order to prevent massive failure of the dam. In most cases, stability can be improved by effectively flattening the slope of the dam as shown in Figure 2, but this is not possible in every case. Occasionally, a tailings dam is constructed adjacent to a natural or legal boundary so that it is not possible to construct a conventional berm or to reduce the slope angle with earth moving equipment. Even a terracing process would require removal of the material and this may not be practical. In such a situation, an alternate scheme to improve stability must be found.

Jan 1, 1974

By J. L. Sloughfy

The size distribution and mechanical strength of the iron ore pellet burden are important parameters in determining the efficiency of the blast furnace. From the very outset, the guiding principle of our pellet quality improvement program was that these parameters are also the key to improving productivity and cost control at the pellet plant. Recognizing the need for improved blast furnace burdens and for higher productivity and lower costs at the pellet plant, Carol Lake operators, in conjunction with the IOC Pellet Quality Committee, established the following goals for the improvement of Carol pellets: [ ]

Jan 1, 1981

By J. Trouw, W. de Bruijn, A. van Sandwijk, R. H. Heerema

Differential reduction and expansion or shrinkage of hematite under the influence of intimately associated foreign oxides may be a source of stress formation and sinter degradation during blast furnace reduction. To study specific effects, synthetically prepared hematite powder evenly doped with 1 % by weight of several elements present as oxides, was pressed into tablets and sintered at high temperature prior to reduction. Continuous theimogravimetric and dilatometric analyses were performed on the sintered tablets as these were being subjected to reduction under simulated blast furnace time/temperature/gas composition conditions up to 1183 K. These findings were coupled with observations on the microstructure of tablets removed from various stages of the reduction process. The results indicate that the degree of expansion or shrinkage of hematite during reduction is highly dependent upon impurities associated with the original material; marked differences in reduction rate and microstructure were observed as well. An important finding is that the influence of a particular additive can also strongly vary from one reduction stage to the next. The reduction behavior appears to be affected by the physical and chemical nature of the associations formed by the added elements.

Jan 1, 1990

Production In 1993, it was estimated that United States mine production of barite increased 24%. Barite consumption, either sold or used by grinding plants, increased by 39% and imports increased 4%, according to the US Bureau of Mines (USBM). Nevada continued to be the leading producer of barite with 80% of the total, followed by Georgia. It is estimated that 83% of the domestically mined barite was used as a weighting agent in drilling fluids. The remaining 17% was used in barium chemicals, glass or as a filler. Most of the production from Missouri, Georgia and Tennessee was used in the non-oilfield sector. Prices The value of domestically produced barite, f.o.b. mine, decreased 1%, according to the USBM. The declared value c.i.f. US port of all imported crude barite during 1993 decreased from $40.09/t ($36.37/st) in 1992 to $37.72/t ($34.22/st). Uses Of the total barite used by grinding plants and chemical manufacturers, it is estimated that 90% was used in drilling fluids and 10% in the non-oilfield sector. This included barium chemicals, fillers in paper, plastics, brake shoes and glass. The tonnage consumed in the drilling fluids market increased due to the higher average rig count during 1993. The average number of rotary rigs operating in the United States was 754, 5% greater than the 1992 average of 717. Imports Crude barite imports in 1993 were 443 kt (488,000 st) greater than 1992, representing an increase of 137%. Imports accounted for 67% of the barite consumed (apparent) in the United States.

Jan 1, 1994

By George A. Snyder

The presence of moderate to high concentrations of colloidal clays in coal preparation plant waters can cause serious operating and economic problems for a coal company. Among the host of possible problems are the following: 1) Poor separation of clays in the plant thickener, resulting in: a) Increased ash in the clean coal. b) Increased specific gravity of the wash water and decreased coal recoveries at the desired quality. c) Increased thickener operating costs in trying to overcome the problem. 2) Decreased solid concentrations in the thickener underflow and increased pumping requirements to meet solids withdrawal requirements.

Jan 1, 1979

By Zohreh Kazemi Motlagh, Evan J. Owen, Virginia T. McLemore, Jakob Newcomer

Five-element style deposits are unusual hydrothermal systems that are typically characterized by a nickel-cobalt-arsenic- silver-bismuth metal assemblage. This mineralization is often represented by abundant native silver, arsenic, or bismuth, and followed by nickel, cobalt, and iron arsenides (skutterudite, safflorite, nickeline, rammelsbergite, and lollingite). The Black Hawk district in Grant County, New Mexico is one of the few examples of this mineralization style in the United States. Despite the differences in formation temperature, depth of emplacement, and host rocks between five-element style deposits worldwide, there are commonalities in mineralogy, ore texture, and composition. A detailed exploration of the native metal and arsenide phases will be performed to compare ore forming fluids between systems and the effects on styles of mineralization and paragenesis, as well as to aid in broader classification of the deposit style. Mineralogy and mineral relationships of the Black Hawk District and other five-element deposits worldwide will be characterized by reflected light petrography, scanning electron microscopy, X-ray diffraction, and electron microprobe analysis. Mineralogical phase diagrams will be generated to better understand the driving processes and evolution of the systems through native metal and arsenide precipitation.

Feb 1, 2024

By B. Yarar

Samples of coal from an adit in the Fording River District of British Columbia showed hydrophilic properties between depths of 0-24.5 meters and was naturally hydrphobic at higher depths. Laboratory experiments indicated that weathered samples (i.e., those mined at 0-24.5m) could be upgraded by froth flotation at pH<2 following slimes removal. The i.e.p. of samples varied regularly between pH=1.6-4.1, the weathered fractions being at the lower end of the pH scale. These values followed a pattern comparable with the flotation behavior of samples. A patchwise structure for coal surfaces determining the resultant disjoining pressure, which in turn determines flotation-non flotation relationships is postulated.

Jan 1, 1982

By R. W. Bruce

The normal practice for processing complex sulphide ore has been to grind with steel balls and/or rods in steel mills before flotation. Little thought had been given to the effect of grinding media on flotation selectivity of copper-lead -zinc ore until 1960 when Rey and Formanek(1) published their experiments on sphalerite floatability after grinding in a porcelain mill with ceramic pebbles. The studies by Rey and Formanek had a pronounced effect on the milling of copper-lead-zinc ores in Canada and possibly throughout the world at a time when autogenous grinding was creating a great deal of interest. The impression was created, and possibly still exists with some mill men, that grinding an ore in the absence of steel will result in a loss of selectivity between copper, lead and zinc minerals. This is in spite of the fact Rey and Formanek&apos;s experiments showed that the "naturall floatability" of sphalerite was not apparent after grinding in a porcelain pebble mill in an alkaline pulp.

Jan 1, 1976

By D. W. Park

Longwall mining is popular in underground coal production in the United States due to higher production rates and safety concerns. Because of the extreme complexity, it is necessary to plan an adequate design to achieve a safe and efficient working place. The proper sizes of yield and abutment pillars and panels can be determined by simulation using numerical modeling techniques. By means of three-dimensional modeling, stresses to be imposed on the pillars, panels, gob, and powered supports can be analyzed. In this study, an initial three-dimensional finite element model was developed and then modified into four different models. Using these models, the numerical outputs of distributed stresses on three different sizes of yield pillars, three different sizes of panels, and two different sizes of abutment pillars were compared and analyzed to determine the most adequate pillar and panel sizes. Progressive failure theory based on the Hoek and Brown failure criterion was used to determine redistribution of stresses in the yielded and failed areas in the longwall mine.

Jan 1, 1992

By S. K. Sharma

The Bureau of Mines has investigated the fundamentals of the flocculation process. The objective of this study was to determine the effects of various physico-chemical parameters such as shear rate, polymer dosage, and polymer concentration on floc growth and to determine the applicability of a model in predicting polymer flocculation behavior. A rapid in-line particle size analyzer was used to follow the progress of both the floc growth and the breakage as a function of time. A genetic algorithm (GA) was used to determine the unknown parameters in the model and to fit a curve to the experimental data. Results show that the model, using GA as a tool to determine the unknown parameters, reproduces the experimental data with only reasonable accuracy and was relatively insensitive to the parameters. Results of the flocculation study showed that increases in polymer dosage had greater effect on the time required to reach the maximum floc size than on the floc size itself. It was also determined that, given all the aforementioned parameters, the degree of slurry mixing during the flocculation process had the greatest bearing on the floc growth.

Jan 1, 1993

By E. R. Torak

Custom Coals, International has installed and is presently testing a 225 kg/hr. (500 lb/hr.) micronized-magnetite, fine-coal cleaning circuit at PETC&apos;s Process Research Facility (PRF). The cost-shared project was awarded as part of the Coal Preparation Program&apos;s High Efficiency Preparation Subprogram. The project includes design, construction and testing of a fully-integrated, bench-scale circuit, complete with feed coal classification to remove the minus 30 micron slimes, dense-medium cycloning of the 300 by 30 micron feed coal using three different size micronized-magnetite mediums, and medium recovery circuits using drain and rinse screens and various stages and types of magnetic separators. This paper describes the project circuit and goals, including a description of the current project status and the sources of coal and magnetite which are being tested.

Jan 1, 1996

By M. Takayasu, J. Y. Hwang, F. J. Friedlaender, G. Kullerud

Al unite has been used as raw material for producing alumina and potassium sulfate fertilizer in Russia for many years. In the United States, this mineral has not been commercially processed though reserves of 5 to 10 billion tons of alunite ore have been estimated. Major constituents of these ores are quartz and alunite. The minerals are finely intergrown and liberation occurs below 10 µm. Adequate separation techniques for such ultrafine particles have not been developed. A new method for the beneficiation of al unite ore is proposed in this study. This method utilizes a small amount of fine magnetite upon which the liberated quartz is selectively flocculated. The co-flocculated magnetite and quartz are then separated from the alunite in a high gradient magnetic separator. Clean products, e.g., an al unite concentrate of 90% grade with 80% recovery, has been obtained from Utah ore. Techniques for selective co-flocculation of magnetite and quartz, separation of the carried quartz, and recovery of magnetite after separation are discussed.

Jan 1, 1987

By M. F. Gleason, S. Burns, J. R. Arnold

In 1986, Gold Fields began negotiations with a large Nevada electrical power utility to supply power for its Chimney Creek mine in northern Nevada. After the long negotiations reached an impasse over various costs associated with the power line, a decision was made by Gold Fields to generate its own power. Self-generation is not uncommon overseas, but it is rare for any but very large or very small operations in the United States. Surprisingly, under certain conditions a mine can generate its own power profitably, and Gold Fields has found that the associated operating and maintenance problems are minimal. The following report details what factors went into this decision and how it works. Hopefully, it can serve as a guideline for those who may find themselves in a similar position. History In the spring of 1986, Davy McKee Corp. was contracted by Gold Fields Mining Corp. to provide design engineering and construction management for the chimney Creek Mine. Chimney Creek is located about 50 mi northeast of Winnemucca, NV in a remote part of Humboldt County. The nearest industry using utility power was the Pinson Mine, about 13 mi from the proposed plant site. The existing electric line was not capable of carrying another mine the size of Chimney Creek, which required 29 million kwh per year. There were three options available to Gold Fields for the power supply: 1 )Power could be supplied by the public utility from a coal-fired plant about 30 mi away by constructing a new line to the mine,

Jan 1, 1991

By T. J. Joiner

A critical demand exists to develop new mineral resources, and the need for exploration techniques to supplement costly test drilling is becoming; more acute. In the past few years more industries have begun experimenting with geophysical methods to locate and define mineral deposits and delineate reserves. The new techniques have proven profitable in many instances. As a part of a broad long range program to study the mineral resources of Alabama, and in response to requests from land owners and mining companies, the Geological Survey of Alabama is investi¬gating the occurrence of bauxite and kaolin deposits in the Eufeula area. This project is supported by special funds appropriated for this purpose by the Alabama Legislature.

Jan 1, 1966

By Richard Komarek

When limestone (Ca03) is calcined in rotary kilns to produce quicklime (CaO), it is not unusual for 10% to 20% of the stone to abrade and emerge from the kiln as quicklime fines (-6.3 mm or -0.25 in.). While there are various industrial processes that can use fines, handling and shipping is tricky and dangerous. Due to the highly caustic nature of quicklime, airborne dust easily bums eyes and skin. On the other hand, money has already been invested in mining (or buying) the raw material and in the equipment and energy needed for calcining. Discarding the fines will not only waste that investment, but add even more cost in transportation and possibly dumping charges. So the question becomes, how can fines best be turned into a revenue-generating asset? Some plants convert leftover quick-lime fines into calcium hydroxide - Ca(OH)2, also known as hydrated or water-slaked lime - for sale into agricultural applications. For farm uses, hydrated lime fines are preferred over quicklime because they are easier to handle. And they are favored over raw limestone fines for their higher concentration of calcium and greater solubil¬ity. From the producer&apos;s viewpoint, quicklime fines are ideal for this use because they go through hydration faster than the larger chunks of quicklime. Those larger chunks, or "pebble lime," are more readily salable and more easily handled, for such uses as steel, copper, aluminum and magnesium production, water waste treatment, chemical, paper, glassmaking and flue gas desulfurization in coal- fired boilers.

Jan 1, 1993

By John A. Patterson

There are certain data handling techniques used by statisticans that can help one to calculate the size of an orebody and to develop some of the relationships between size, cutoff grade, average grade, mining cost, and profit. Knowing the relationships amongst these factors can help determine the most desirable operating conditions. A statistical technique that we will use is data grouping. This allows us to work with relatively few groups instead of many samples, If we were able to segregate the ore in an orebody into grade groups, add the amounts in each group, and plot the sums as a curve, we would get something like Figure 1. A smooth curve develops when the grade classes are small enough, otherwise a "stair step? histogram results. The area under the curve, being the sum of the tonnages in all of the grade classes, is proportional to the total number of tons in the orebody. If we take the data of a distribution such as Figure 1 and add the tonnages above a specific grade we have in effect a cutoff grade

Jan 1, 1958