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At the 25th Peruvian Mining Convention, the start-up of Antamina was called ?the mining event of the year.? Antamina, one of the largestcopper-zinc mines in the world, began operations in May 2001.Augusto Baertl is Executive Chairman of Compañía Minera Antamina, the operating company. He said in a convention address that Antamina would be in full production in 2002. ?I would like to stress that Antamina is, in every respect, a highly stringent operation, as it intends to be the Peruvianmine of the future,? Baertl said. ?Antamina has set the target of being, and remaining throughout time, a model mine as to technology, environmental practices and social responsibility.? [ ] In the areas of technology and operations, Baertl noted that ?we have incorporated the best engineering design available and state-of-the art technology for mining, grinding and transportation processes, among others.? In the environmental area, he said that ?we have carried out careful environ-mental impact studies and have incorporated modern technologies and methods to control and minimize any environmental impact.? In the social field, Baertl noted that ?our relationship with neighboring communities is being developed under the premises of the social responsibility philosophy.? These include popular consultation processes, environmental committees and conciliation discussion committees. The purpose, he said, is to encourage communities located within the area of influence of the project to find and lead by themselves their path toward sustainable development, beyond the life of the operation itself.?

Jan 1, 2001

By Jerry C. Tien

The rare earth elements (REEs) are a group of 17 chemical (metallic) elements. REEs are used widely in high-technology, clean-energy products as well as weapon systems. China's dominant position as a producer of over 95% of the world REEs output and the world's increasing reliance on REE products have highlighted concerns about the future availability of rare earths in recent years. This paper briefly reviews the REEs world reserves, production, consumption, the impact of our heavy reliance on REEs products and China's changing policies on REE export on world supply chain.

Jan 1, 2013

By J. E. Rourke, O&apos

This paper describes the use of index testing to obtain rock properties that are useful in the design and construction planning of an underground development for civil engineering or mining projects. The index properties discussed include: point load; Schmidt hammer hardness; abrasion hardness; and total hardness. The first two index properties correlate to uniaxial compressive strength (UCS) and Young's modulus. Discussions are given on empirical, normalized relationships of UCS to rock mass properties and the integrated use with semi-empirical, geotechnical design methods. The hardness property indices correlate to construction performance parameters and some relevant experience is cited. Examples of data are presented from an index testing program carried out primarily on siltstone, sandstone and limestone rock core samples retrieved from depths up to 1005 m (3300 ft) in a borehole drilled in the Paradox Basin of eastern Utah. The borehole coring was done for a nuclear waste repository site investigation.

Jan 1, 1990

By Carmel Bofinger, Maureen E. Hassall, David Cliff, Eric Stemn

e Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

By L. C. Morales

During my College days in Mexico City, my Mineralogy Professor used to say "Mexico is the Horn of Plenty, rich in minerals, and it is easier to say which minerals are not found instead of stating all that exist. He said that the only ones missing are bauxite, diamonds and titanium ores." Today, twenty years later, a rutile mine in Oaxaca is in successful operation. Mexico has an area of approximately two million square kilometers, with volcanic activity, large shores and mountainous areas reaching as high as 6,000 meters above sea level. These conditions are favourable for most mineral deposits, some -of commercial value and others as a source of mineral samples only. (fig. No.1) In addition to vast mineral wealth, Mexico has -another valuable asset in .his people. Even before the discovery of America, natives were successfully mining metals, and during the Colonial --days, the mineral deposits were mined to increase the wealth of Spain, and it increased the --knowledge of mining. All this experience was passed along from generation to generation, and created a tradition of mining and minerals processing engineers, that currently account for approximately 182,000 persons supported by mining related activities.

Jan 1, 1994

By W. C. Morgan

Recently passed federal strip mining legislation officially emphasizes that the increased coal production required by this country through surface mining is going to be obtained only with stricter environmental standards. Dozing overburden down the hillside in Appalachian contour mining or leaving drag1ine spoils in area mining is now taboo and it is now or will soon be necessary to return the disturbed land to as good or better condition than before mining. These new restrictions will create a need for new and better ways to do the job. This paper describes one approach for utilizing scrapers and dozers to strip all of the overburden and to replace that overburden in an environmentally satisfactory fashion. The objective was to do this at a lower cost than that possible with the traditional dragline system using dozers and scrapers for reclamation and topsoil handling. In area stripping, the dragline has been able to move overburden at an extremely low cost. Operating costs of 8-13¢/bcy are typical in many operations where rehandling is not required. However, the cost of leveling the spoil piles and rehandling topsoil add considerably to the low basic cost of drag1ine stripping.

Jan 1, 1977

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 James J. Meadows, Jason D. Pampena, Emanuele G. Cauda, Lauren G. Chubb

Respirable crystalline silica (RCS) found in dust generated by various mining processes is an important occupational hazard in the underground coal-mining industry. Exposure can lead to disabling and incurable diseases, including coal workers’ pneumoconiosis (CWP), silicosis and lung cancer [1,2]. Clusters of rapidly progressive CWP have been observed in the Appalachian regions of eastern Kentucky and southwestern Virginia, and recent cases have been generally more severe and showing more rapid progression. CWP is approximately four times as common among long-tenured underground coal miners in central Appalachia than long-tenured underground miners in the rest of the United States, and 20.6 percent of long-tenured underground miners in central Appalachia were suffering from the disease as of 2017.

By S. Dempsey

Since its passage in 1872, the Mining Law has been modified on several occasions to meet the changing needs of America's society and economy. Despite its evolution, the Mining Law continues to be criticized as outdated. This paper briefly traces the major points in the history and evolution of western mining laws, and reflects on the current status of ongoing discussion to reform the 1872 Mining Law.

Jan 1, 1997

Water conservation and compliance strategy can be cause for success or failure of a new or existing mining operation. Water accounting at outset, and pit and waste dump planning, may not fully consider total inflows, or sediment loads encountered during mine life. Environmental impact assessments, and permitting often dictates the rules, and these may change, to be more stringent, during course of mine development. This paper will identify techniques to control unprojected fresh water, or increased surface water flows in surface mine operations.

Feb 23, 2014

By Shingo Morimoto, Toru Sasaki, Masato Shinji

"1. INTRODUCTIONTunnel face stability is one of the most important consideration in New Austrian Tunneling Method. In general, if all of the material properties of ground can be obtained through the field investigations, the tunnel face behavior can be predicted using numerical simulation prior to tunnel construction. However, estimating the safety of a tunnel face is difficult, especially in cases where the ground is very weak such as in an urban area.In this study, numerical analyses of tunnel excavation in very weak ground conditions, such as a low cohesion and low internal friction angle, were carried out. The relationship between the average shear strain distribution on the tunnel face and the overburden was analyzed. This relationship estimates the shear strain of the tunnel face relative to the critical shear strain obtained by the ground properties. The critical shear strain was defined as an allowable value for the maximum shear strain. We proposed the allowable overburden as tunnel face stability index (TFI) that satisfies the critical shear strain criterion of ground. Finally, a design chart of the allowable overburden for various cohesion values and friction angles of ground was created. This chart is useful in the preliminary tunnel design stage to judge the necessity of additional counter measures against normal tunnel support design.2. WEAK GROUND MODELING AND ANALYSIS PROCEDURE2.1 Setting material propertiesWith reference to a past study1), the material properties were adopted on the basis of material properties in the standard worst rock classification case called “DII”2) for standard support pattern of weak ground in Japan. The typical material properties for “DII” are listed in Table 1. In addition, Fig.1 shows the distribution of the representative weak ground according to cohesion and internal friction angle. When the internal friction angle is relatively high and the cohesion is weak, the ground is categorized as sandy ground. Furthermore, when the internal friction angle is low and the cohesion is strong, the ground is categorized as clayey ground."

Jan 1, 2016

By S. Gering, R. Ruiz, C. H. Calderon-Arteaga, J. Barrios

"INTRODUCTION Located in the northeast corner of Zacatecas State, Mexico, the Peñasquito Operation is comprised of the Peñasco and Chile Colorado (Brecha Azul) deposits. Open pit mining (pre-stripping) began in 2010 and full production commenced during 2011. The open pit mines feed both a sulphide concentrator (mill) and a heap leach pad. The project is owned by Goldcorp, Inc. Penasquito is a poly metallic deposit with Au, Ag, Zn and Pb being recovered as payable metals. As a consequence of lower grade ores expected with advancing mine-life Peñasquito is facing a declining metal production profile. To maximize returns and asset value plant modifications including the addition of a carbon pre-float circuit and a pyrite leach circuit to improve recovery are currently being undertaken. This carbon pre-float circuit will enable the recovery of precious and base metals from carbonaceous sediments. This material is currently being stockpiled. With the associated increase in complexity in the process circuit, the requirement of the ore control system to accurately predict ore feed characteristics is critical to maximizing metal recovery at the Penasquito operation. The addition of the carbon pre-float circuit was also a key driver in allowing the Chile Colorado open pit to be developed. These conditions alongside Goldcorp’s drive to increase profitability, and maximize net asset value has created challenges. These challenges are numerous and are multifaceted, however the ability to accurately route materials from the ore control system is critical to site success, and some of these challenges have been overcome by the adoption and implementation of a new ore control (OC) technology. Examples of these technological innovations in the ore control program are discussed in this paper and include improvements in geo-modeling, material routing and reconciliation. Successful implementation of these elements has led to significant improvements in selectivity, performance, and data management, while reducing the variance between planning and execution, thus helping to drive overall improvement across the operation."

Jan 1, 2018

By A. Ghosh

Commonly used predictors of ground vibration from blasting, being linear in log-log plot, do not model the underlying physics of wave attenuation. Amplitude of the wave decays with distance due to geometrical spreading and inelastic attenuation producing a nonlinear carve in log-log scale. The nolinear decay of seismic waves has also been observed from non-explosive sources, such as, pile driving, drop hammer, traffic, etc. The improved predictors, by explicitly taking these two mechanisms into consideration, model the data trend extremely well at all distance ranges. Actual field data from different studies have been used to validate the improved models.

Jan 1, 1991

By J. B. Hiskey

The principle oxide minerals of molybdenum are wulfenite (PbMoO4), ferrimolybdite (Fe2(MOO 4)3.nH2O), powellite (CaMoO4), and ilsemannite (Mo304). Wulfenite is found in Arizona, New Mexico, Nevada, Utah, California, and Montana. It is also found in the states of Sonora and Chihuahua, Mexico. Prior to 1915 wulfenite ores were the primary source of molybdenum. The solubility of wulfenite in hot sodium sulfide was first noted by Bonardi(1) during attempts to sulfidize wulfenite material prior to flotation. He identified lead sulfide and soluble sodium molybdate as reaction products. Bacon (2) sulfidized wulfenite in preparation for flotation and by X-ray analysis found the reaction product to be lead sulfide. Holmes(3) made an extensive investigation of the extraction of molybdenum from wulfenite concentrates by leaching. Nearly 100% molybdenum extraction was possible from -100 mesh samples leached for 15 min with 10% sodium sulfide solution at room temperature. Molybdenum extraction from -100 mesh samples after leaching 30 min at a temperature of 45°C using 2, 4, and 6% sodium sulfide was about 32, 79, and 98% respectively. The extraction showed little sensitivity to time, temperature, or particle size using 10" sodium sulfide solution.

Jan 1, 1976

By V. O. Tenorio, K. W. B. Requist

As the mining industry begins efforts to examine the feasibility of extraterrestrial resource utilization, the extraction and processing of icy regolith containing water and other volatile materials will be the initial focus for future expansion of capabilities. Pure water is essential for human consumption, and a source of oxygen and hydrogen. The latter, along with the volatile materials, lend themselves to the creation of fuels that may be used for further space exploration at distances not currently feasible. For any extraterrestrial scoping project, the transport of materials to geoscientists remains virtually impossible. Therefore, analysis must be done in-situ, possibly millions of miles away from the nearest human. To address the need for geologic resource estimation in the absence of geoscientists, an infrared framework has been developed for the analysis of water ice content in simulants of permanently shaded lunar regolith. This framework relies on a convolutional neural network model for the rapid analysis of percent water ice content in samples, at which point standard geostatistical methods may be employed.

Feb 1, 2023

By Dennis Z. Mraz, Maurice B. Dusseault

INTRODUCTION In 1982 and 1983, as part of the mine design program for a New Brunswick potash mine, series of laboratory tests were conducted on potash and salt samples obtained during the mine exploration program. Concurrently, two rock mechanics monitoring programs were initiated in-situ the short term test at site A, and the long term test at site B (figures 1 and 2). SHORT TERM TEST (FIGURE 1) The purpose of this test was to obtain a quick confirmation of laboratory data and comparison of the rock response to excavation with the data available from Saskatchewan potash mines. Instrumentation in the main drift was installed on Day 4 after excavation, and the pressure cells were pressurized on Day 33. The packer type cells in the east crosscut were pressurized on Day 25. Excavation of the west cross-cut was begun on Day 71. This "mine by" test has provided important information required for calibration of laboratory tests, as will be shown later. The test data recorded are shown in a series of diagrams: a. initial room closures, main drift-figure 3; b. convergence graphs, main drift-figure 4; c. stresses recorded, main drift-figures 5 to 8 and, d. stresses recorded, east crosscut - figure15 Three types of instruments were used in this test. In the main drift. Saskatchewan Research Council water type hydraulic inclusions. encapsulated in potash, were used to measure lateral and vertical stresses. In the east crosscut a home-made packer type hydraulic inclusion was used to record radial stresses. The convergence stations consisted of end-grouted bars of reinforcing steel. LONG TERM TEST (FIGURE 2) The purpose of the long term test was to study the steady-state behaviour of a single opening in potash. Site B was placed in a remote area of the mine, well away from any anticipated early mining activities. To assure homogeneity of rock mass, the site was placed within a 30 meter thick vertical limb of a syncline-shaped ore body contained within a 360 metre thick vertical section of salt rocks. It was excavated mechanically as close as possible to the designed square cross-section for the entire length of the room. The square cross- section was chosen in order to achieve a comparable geometry in vertical and horizontal directions; that is, to eliminate any undesired effects of geometry interaction with lithostratigraphy which might have generated non-homogeneous behaviour. The site was extensively instrumented. As in site A, the convergence stations consisted of end-grouted bars of reinforcing steel. However, in order to avoid any measurement inaccuracies which would be associated with the brittle yield zone in the opening walls, bars were placed to the same depth in opposite sides of the opening. This allowed the convergence measurement to be obtained as the absolute convergence between two points, rather than the convergence of a single point with respect to a potentially unstable reference. For stress measurements the Saskatchewan Research Council cells were placed vertically, laterally and radially. Unfortunately, due to cost considerations, it was decided to use a compacted sand, rather than grout, to encapsulate the cells in the boreholes. Due to the extremely small strain rates, only radial ly placed cells could be adequately pressurized. The rest of the cells did not perform adequately, and are currently being replaced.

Jan 1, 1986

By Raymond E. Zimmerman

The use of standard dense-media cyclones is well known, as they have been in use for many years. They are especially well suited for operating at low separating densities and for treating difficult coals containing a high percentage of near-gravity at the point of separation. Very few modifications of the basic design have ever been made. The author recently, however, has been interested in the development of a new type of dense-media cyclone that has been produced in Japan. He has observed the testing of this unit and has collected much data which he feels should be of considerable interest to coal preparation engineers. He feels that this unit, called the Swirl Cyclone, may be of substantial value as an alternate to the standard cyclones. It is certainly worthy of further investigation. There has been relatively little written in English-language publications on the Swirl Cyclone. It was briefly described at the Fifth International Coal Preparation Congress. I It has been described in a general manner by the author in two prior publications. 2, 3 This paper proposes to describe this device in more detail and at the same time submit technical data illustrating its wide characteristics.

Jan 1, 1977

By C. E. Capes

The spherical agglomeration process provides an attractive method for the cleaning and recovery of fine coals in the form of compact oil-bonded pellets. In treating a washery effluent containing 50% minus 20 micron material by this technique, the slurry was first mixed under vigorous agitation with oil to deash and dewater the fine coal. The flocculated coal pulp was then formed into larger agglomerates on a modified balling disc. The operation of a semi-pilot scale process is described and an analysis of some of the operating and system variables is given. A semi-theoretical expression to predict the final agglomerate size under various conditions is derived and compared with the experimental data. Coal producers are faced with a growing requirement to clean and recover fine mesh coals. Greater mechanization of the extractive and preparation processes has resulted in finer-sized products containing larger quantities of associated foreign matter and preparation plant effluents contain quantities of fine coals which are potentially valuable. These losses will probably increase with the expansion of production and will require the development of effective disposal and utilization processes under pressure of the lack of adequate disposal areas, the enforcement of air and stream pollution laws, and the economic need to obtain the maximum yield of salable product(1)

Jan 1, 1970

By C. Iglesias

Innovation in the tilemaking ceramic industry is stressing properties like powder flowability, ability to toughen green tiles, so turning technological requirements of ball clays ever stricter in terms of plasticity, dispersion in water, rheological behavior, workability in the green state, refractoriness and firing colour. Technological performance of ball clays was improved by taking as benchmark the highest quality raw materials on the market. The mineralogy, plasticity, methylene blue index and ceramic response of the Patagonian ball clays are analogous to those of European clays, but improvement is needed to approach the highest quality materials. On this basis, the Frente A, Super, Puma, and Lote 8 deposits were selected and their characteristics enhanced by additions of highly plastic and white-firing corrective clays targeted on the benchmark. Porcelain stoneware formulations, containing improved ball clay mixes, were experimented at both laboratory and industrial scale. The improved ball clays behave like the best raw materials currently used, although modest changes occur in the mechanical properties, water absorption and whiteness of the fired products.

Jan 1, 2010

By J. C. Judd

The U.S. Department of the Interior, Bureau of Mines investigated solvent extraction methods for recovering gallium from filtrates produced from sulfuric acid leaching of hydrometallurgical zinc residues. These filtrates typically had pH values of 0 to 0.5, too high an acid content for effective gallium recovery by traditional extractants. Of the nine extractants studied in batch tests, 0.3M octyl phenyl acid phosphate (OPAP) in a kerosene diluent was the most effective extractant for gallium recovery, extracting up to 99.9 pct of the gallium. This high extraction was possible when the iron in solution was maintained in the reduced ferrous state. Batch tests also showed that a 1.5M-H2SO4 strip liquor recovered 98 pct of the gallium from the loaded OPAP. A continuous solvent extraction system was designed and operated based on McCabe-Thiele analyses of equilibrium loading and stripping isotherms. When 12 L of leach filtrate containing 0.32 giL Ga and 20 giL Fe were pumped through the system in 32 hr, results showed that 95 pct of the gallium was extracted in four stages at an A:O ratio of 1:1. Stripping the loaded solvent with a 1.5M-H2S04 liquor recovered 94 pct of the gallium in four stages at an A:O ratio of 1:4. A two-stage, 50-pct-phosphoric acid strip successfully removed ferric iron from the OPAP, allowing high gallium extractions to be maintained.

Jan 1, 1990