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By Mats Keisu, Bengt Niklasson

The Sofia project has increased the level of knowledge and technique within tunnelling, drifting and contour blasting.

Jan 1, 1992

In 1988, at the request of members of the Society for Mining, Metallurgy, and Exploration (SME) Inc., the president of SME formed Working Party No. 79, Ore Reserve Definition. Its mission was to develop guidelines for the public reporting of exploration information, resources and reserves. These guidelines were published in the April 1991 issue of Mining Engineering (pp. 379-384), and as a document entitled “A Guide for Reporting Exploration Information, Resources, and Reserves” in January 1992. Work continued on an ad-hoc basis until 1996. Working Party No. 79 was then renamed the SME Committee on Resources and Reserves and became a standing committee.

Jan 1, 1999

By M. L. Baharani

Looking for an idyllic paradise that has investment and business potential as spectacular as the stunning views of mountains, the rich Ganesh Himal zinc-lead deposit exposed between 4,050 m and 5,000 m is the answer. Arising from the sea floor in a span of 55 million years, the enchanting Himalayas had remained one of the most potent factors influencing the Asian region. The challenges of the mighty Himalayas notwithstanding, it continues to provide opportunities for the humankind in optimum usage of the natural resources and sustainable development. Optimal management of natural resources in mountain areas through decision support tools offered by remote sensing will go a long way in realization of the Ganesh Himal Zinc-Lead Project. The authors have a real life endeavor spanning over 37 years in developing a mining industry in a mountainous region of Nepal and an attempt to integrate with the development of other natural attributes of the region. With rapid acceleration of science and technology, humankind has acquired power to transform his environment countless ways and on an unprecedented scale. While mineral resources are the pillars on which we have built industry and infrastructure, industrial countries in the North have been in the forefront of technological advancements, the developed countries of the South have been at the receiving end of exploitation of mineral resources worldwide. A relationship with natural environment, re-crafted by the civilizing impulse, to meet human demands are upcoming challenges for management of natural resource in sustainable manner for a livable world.

Jan 1, 2008

By V. I. Kefeli

Public-private partnership efforts are working to create green landscapes from abandoned industrial sites. Fabricated soils, potentially an essential element of such landscapes, are designed to substitute for topsoil on the areas free from ground cover and plant community. The aluminosilicate matrix and humus form the soil micelle - the primary unit of any soil complex. Humus formation is a process based on carbon-nitrogen interaction. Sources of carbon can be materials rich in easily composted products like cellulose and polyphenols (plant leaves) or aged lignin polymers (saw dust from different woody plants). The pathways of carbon-nitrogen complexes are discussed. Properties of the fabricated soil components were examined by bio-tests and plant models.

Jan 1, 2002

By B. McFadzean, M. Tadie, T. Dzingai, M. Becker

Ores from a single deposit may exhibit extensive variability in their mineralogy and texture. The ability to quantify this variability and link it to mineral processing performance is one of the primary goals of process mineralogy. This study focuses on the effect of alteration in three platinum group element ore samples from the Great Dyke in Zimbabwe – two of which were more pristine compared to the third, which was locally classified as ‘oxidized’ ore. These ores are known to be characterized by varying degrees of alteration, resulting in numerous challenges in flotation and affecting both grade and recovery. Alteration, by near-surface oxidation, of the valuable base metal sulphides and platinum group minerals resulted in lower flotation recoveries of Cu, Ni, Pt, and Pd. Evidence of incipient oxidation was more readily observed in the base metal sulphide assemblage than the platinum group mineral assemblage, even though the loss in recovery (because of oxidation) was most significant for Pd. Alteration through hydration resulted in a significant increase in mass pull and dilution of concentrate grade through the inadvertent recovery of naturally floating gangue comprising composite orthopyroxene and talc particles. In this study, the amount of naturally floating gangue was more strongly correlated with the talc grain size distribution than the grade of talc in the flotation feed. The oxidation and hydration alteration reactions are not necessarily mutually exclusive, although one may be more dominant than the other, giving rise to ore variability.

Sep 1, 2021

By F. J. MacPherson, A. C. Caron

"Cassiar Asbestos Corporation Limited is at present B,C.'s only asbestos mining company, and has been actively engaged in the management and operation of the Cassiar Mine since the early 1950's. The Cassiar operations are located between 3,500' and 6,600' elevation in a secluded mountainous area of northern B.C., approximately 100 miles by road southwest of Watson Lake in the Yukon Territory. Climatic conditions in this area range from mild warm in the summer, to extremely cold during the long winter period.The minesite itself is located over a mile above sea level at the top of McDame Mountain, where year round 24 hours per day miners extract the chrysotile ore from the surrounding waste by standard open pit techniques. The ore body dips into the mountain at about a 45° angle, and as the mining progresses, larger stripping ratios are required. Waste to ore ratio this year will be more than 10 to l whereas only a few years ago ratios of 3 or 4 to l were possible. After drilling, blasting, and loading by shovel onto trucks, the asbestos ore is transported to the Primary Crushing Plant for crushing prior to transport by aerial tramway more than three miles to the Concentrator and Mill in the valley below, where the fibre is extracted from the barren host rock serpentine and milled into numerous grades for shipment to asbestos users round the world. The major air usage is associated with the milling process, presently requiring over 500,000 CFM, with future requirements expected to exceed 840,000 CFM by the end of the decade."

Jan 1, 1976

By J. S. Y. Wang, R. C. Trautz

A 9-meter-long drift was constructed in the unsaturated-fractured tuff at Yucca Mountain to evaluate the potential for water seeping into an underground opening. Forty seepage tests were performed by releasing a finite volume of water at a constant rate into short test intervals located in boreholes positioned above the drift. The seepage threshold flux, defined as the liquid-release flux at and below which water will not drip into the opening, was determined for 10 test intervals. The seepage data, observations, and model results indicate that a seepage threshold exists because a capillary barrier diverts water around the opening.

Jan 1, 2000

"The National Mining Hall of Fame and Museum (NMHF&M) announced the 2015 National Mining Hall of Fame inductees and the 2015 Prazen Award winner. This year’s inductees, selected by the National Mining Hall of Fame’s Board of Governors, represent the technology, management, mineral policy, education and health and safety aspects of the mining industry. They envelope a diverse cross section of the mining industry and were selected for being visionaries, leaders, educators and ambassadors.In 2015, Frank F. Aplan, T S Ary, Ralph E. Bailey, John Campbell Greenway and Edward Steidle will join 227 other mining industry honorees when formally inducted into the National Mining Hall of Fame. The Prazen Living Legend of Mining Award will go to the Powell River Project Research and Education Center, a partnership of Virginia Polytechnic Institute and State University (Virginia Tech) and the Appalachian coal mining industry.The 2015 annual induction banquet and ceremony will be the 28th such event and will be held this year in Pittsburgh, PA, on Oct. 23, 2015, in the Omni William Penn Hotel ballroom.2015 National Mining Hall of Fame inductees:Frank F. Aplan is among the most influential mineral processing leaders in both industry and academia. His studies of the processes involved in the preparation of coal and mineral ores are acknowledged worldwide for their broad applicability. An authority on flotation, Aplan is especially known for his studies of the wetting of solids and their control through the adsorption of surfactant films, and for his work on atomic defects on properties and behavior of solid-liquid interfaces."

Jan 1, 2015

By M E. Watson

Minimising dilution and ore loss is an important part of ensuring profitability of a gold mining operation. White Foil open pit gold deposit is a low-grade deposit and therefore managing ore quality is a high priority. Ground movement through blasting can displace ore and waste boundaries up to 10 m from their in situ location and therefore requires stringent ore movement monitoring and adjustment. There are currently only two options for monitoring blast movement – utilising visual targets (commonly lengths of polypipe) but this has widely been replaced by electronic blast movement monitors (or BMM). Regardless of the technology used, the basic principle is to compare the pre- and post-blast locations of the targets to determine the movement of the rock mass during blasting, which is then used to determine the final location of ore and waste boundaries.The Blast Movement Technologies (BMT) BMM system has been used at White Foil since June 2014. The system has been effective and reliable during that time; however, the annual cost of using the BMM system is greater than other monitoring alternatives. As such, the open pit geology team conducted a study comparing the BMM system against the conventional polypipe technique. The objective was to quantify the profit and loss that would occur based on the ore block transformations from both methods. Eight blasts were selected where polypipes were installed in additional holes adjacent to the BMM monitoring holes. The resulting movement vectors from the respective methods were used to create post-blast ore blocks by transforming the in situ ore blocks. While polypipe is a cheaper alternative, the BMM system tracks ore and waste boundaries more effectively resulting in better quality control, enhanced ability to minimise dilution and ore loss thus maximising profit. For these eight blasts, it is calculated that the BMM system resulted in A$664 978 extra profit through a reduction of ore loss. The total cost of a yearly BMM package was recovered in the first two blasts of this study. The primary reason for the difference is that polypipe had a poor recovery rate of 32 per cent compared with 92 per cent for BMM at White Foil. Therefore, the data used to transform the ore blocks was less representative, resulting in inaccurate post-blast ore block boundaries when using polypipe.CITATION:Watson, M E, 2017. Blast movement monitors or polypipe? A study into cost-effective blast movement monitoring at White Foil gold mine, Western Australia, in Proceedings Tenth International Mining Geology Conference 2017, pp 433–440 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 20, 2017

By R. Hogg, Y. Lee, D. E. Rannels

"Lee, Yu-Chen, Richard Hogg, and D. Eugene Rannels. Extracellular matrix synthesis by coal dust-exposed type II epithelial cells. Am. J. Physiol. 267 (Lung Cell. Mol. Physiol. 11): L365–L374, 1994.—Although integrity of the alveolar basement membrane may influence progression of lung injury induced by inhaled particulates, little is known about direct effects of coal dusts on the alveolar epithelium or its extracellu¬lar matrix (ECM). Effects of dust on synthesis of cell and ECM proteins by type II cells (T2P) was thus investigated. Three coal dusts (anthracite no. 867; bituminous no. 1451 and no. 1361) and mine dust MIT-3, of respirable size, were studied as a function of dose and time over 3 days of primary T2P culture. On day 1, 750 µg/ml of 867 were required to increase relative synthesis of ECM proteins (ECM/cell). MIT-3, 1451, and 1361 were without effect. By day 3, 867 or MIT-3 increased ECM/ cell 60-100% at 300 µg/ml; 1451 produced modest, dose-dependent stimulation, whereas 1361 remained without effect. None of the dusts caused significant cytotoxicity. The results show dose- and time-dependent effects of well-characterized coal and mine dusts to modify partitioning of newly synthesized proteins into the ECM and suggest that coal dust exposure may modulate structure or function of the subepithelial basement membrane.basement membrane; cell culture; inorganic dust; lung injury; extracellular matrix deposition; pulmonary epitheliumCHRONIC EXPOSURE to coal dust may be associated with development of pulmonary fibrosis and consequent loss of normal lung function (see Ref. 26 for review). Al¬though the pathways of inorganic dust-induced lung injury are recognized to involve an inflammatory re¬sponse, the underlying pathogenic mechanisms are not understood in detail. Acute and chronic responses to dust exposure involve a variety of interacting cells of the immune system, including macrophages, T cells, and B cells, along with pulmonary fibroblasts. These responses reflect direct effects of the dust particles, as well as indirect effects mediated by soluble factors, including cytokines and eicosanoids (see Ref. 41 for review).Studies of pulmonary macrophages and fibroblasts following silica exposure suggest that dust-induced damage at the airway surface may involve cellular injury through oxidant-mediated pathways. Coal dusts and related inorganic particulates can activate the alveolar macrophage (42) to produce fibronectin (15) and cytokines, such as interleukin-1 or tumor necrosis factor (4) and/or other soluble products which act locally (29) to cause acute cellular injury and to initiate the progression of fibrotic lung damage (16). Type I epithelial cells are typically more susceptible than type II cells to oxidant injury. Type I cell damage and subsequent death leads to denudation of the subepithelial basement membrane (2, 21) and can be associated with leakage of plasma constituents from the pulmonary vasculature into the alveolar compartment (13)."

Dec 1, 1995

By Stuart Brashear, Lee Schettler

The effect of water on several ANFO/emulsion blend ratios are documented by both physical observations and analytical testing to demonstrate the effect even small quantities of water can have on water resistant blends.

Jan 1, 1996

By Charlotte Abena Benyarku, Albert Buabeng, Eric Stemn

The abstract highlights the increasing use of mobile equipment in mining and its contribution to accidents. The research analyzes injury narratives from Ghanaian surface gold mines to understand the involvement of mobile mining equipment in injuries and explore the use of injury narrative data as a human factors tool. The study identified priority human factor issues, such as operating mobile mining equipment, part removal/installation, and the operator's cabin. The use of Sankey diagrams for multivariable analysis effectively identified specific operator-centered issues that warrant further investigation for improved safety interventions.

Mar 29, 2022

By Elaine T. Cullen, Thomas W. Camm

The mentor/learner model is a time-honored approach to teaching, including within the mining industry. Miners know when they see excellence and have a deep respect for experts in their field. By using expert miners as mentors to other, less-experienced miners, training programs can be developed that will have a legitimacy and credibility that resonates with those being trained. Building upon concepts in current theories of adult education, this paper highlights the unique advantages of using mentoring as a teaching method that can make the educational experience both interesting and effective. Current NIOSH safety training materials use these concepts to deliver effective adult learning experiences for workers in the mining industry.

Jan 1, 2002

By N. Grosland, G. Kopp, T. Hunstad, D. Wilder, M. Contratto, S. Rahmatalla, T. Xia

Chronic whole-body vibration exposure, as expected in large construction and mining vehicles, has been associated with neck and back pain and injury.1 While work has been done towards gaining a better understanding of the relationship between vibration and shock and muscle activity of the back musculature2, relatively little information regarding the activity of neck, shoulder and upper arm muscles is known. Today’s equipment designs must conform to domestic and international standards, however these standards do not specifically address the vibration exposure in the head and upper quarter. Further it is not well known how the control configuration within a vehicle (e.g. steering wheel versus arm controls) influences muscle voluntary and reflex activity levels. Greater muscle activity may lead to greater muscle fatigue – which in turn may be associated with greater risk of injury.2 Thus, muscle contractions needed to maintain static postures as well as those resulting reflexively should be considered during an analysis of seating position. Unfortunately, little is known regarding the influence of arm position on head and neck muscle function. The purpose of this study was to investigate the relative muscle activities of 5 neck, shoulder, and upper arm muscles during riding simulations of large construction equipment, using three different arm control options. Methods Five typical heavy equipment ride files were “played back” through a man-rated Servo Test 6-degree of freedom (dof) vibration system. Each ride was repeated using 3 seat and control configurations (steering wheel (SW), floor mounted arm-rest controls (FM), seat mounted arm-rest controls (SM)). Two trials were performed for each ride and seat control combination (each trial: 60 sec of 6-dof and 60 sec of vertical vibration). Five channels of surface electromyography (EMG) of the right-side cervical erector spinae muscles (neck extensors), sternocleidomastoid (neck flexor), upper trapezius (shoulder elevator), biceps brachii (elbow flexor) and triceps brachii (elbow extensor) muscles were collected throughout each ride (~ 2min) using pre-amplified (10x), 1 cm silver bar electrodes, with 1 cm fixed inter-electrode distances (Delsys, Inc). Further analog amplification was set at 10k (1k for one subject), and sampled at 1000Hz using a 12-bit DAQ card and Labview 7.1 software (National Instruments). A total of 7 right-handed male subjects were tested, but only 5 had complete EMG data sets to analyze for this sub-study. EMG was analyzed using root mean square (RMS, in mV) of 20 ms moving windows, and then averaged across the entire trial for a measure of mean total muscle activity (voluntary and reflexive). The muscle activity to maintain the static posture was estimated as the mean RMS EMG over a 1 sec interval just prior to and/or after completion of the ride. Repeated Measures ANOVAs were used to test for with-in subject differences using a = 0.05.

Jan 6, 2006

By Renan Celestino Silva Santos

O presente estudo trata da análise de falha de um cabo de aço utilizado em grua de construção civil. Para a análise da falha foram feitas metalografia, microdureza, análise dimensional e análise por microscopia eletrônica de varredura. Também foram feitos ensaios de tração, a fim de determinar a diminuição da resistência mecânica em decorrência de diminuição de área do cabo. A análise em campo detectou a presença de um dispositivo de acionamento do motor da grua que mantinha contato com o cabo e foi o responsável pela falha. Os resultados demonstraram que todos os fios estavam desgastados. Na maioria dos fios foi detectado aspecto de fratura plana frágil. A análise metalográfica e de microdureza não indicaram nenhum defeito metalúrgico nos cabos. Os resultados do ensaio de tração indicaram a diminuição significativa da resistência mecânica devido à redução de seção dos fios.

Aug 16, 2017

By Carlton D. Hulin

ARE we a "have" or a "have-not" nation in our domestic supply of metals and minerals? Impinging on the ears of a people weary of war and faced with the problems of reconversion to peace, the import of this question has built up with the momentum of an avalanche. Stemming from statistics cited by Pehrson and accelerated by the pessimistic and possibly biased statements of Ickes, hardly an issue of any technical periodical dealing with mining has appeared during the past year but within whose pages was to be found some comment, some discussion of the question: Are we a "have" or a "have-not" nation? We have proved commercial reserves of high-grade iron ore in the Lake Superior region sufficient for 22 years, based upon the prewar rate of consumption; commercial copper reserves to last only 34 years, one fourth being inferred ore; zinc sufficient for nineteen years, over half being inferred; lead for twelve years, two thirds of which is inferred; mercury for only three years. So read the figures. Although admitting that these figures may be extended by new discoveries, by the use of marginal and submarginal ore, and by further technological advances, are we nevertheless to assume complete pessimism in the acceptance of the meaning of these statistics; are we to expect a rapidly increasing dependence upon foreign sources of mineral supply; are we to believe that we are at or near the peak of the "metal age" as has been held by Theodore J. Hoover? Or is some more optimistic viewpoint possible?

Jan 1, 1947

Extraction and Characterisation of Extracellular Polymeric Substances from the Mineral Surface During Bioleaching of Chalcopyrite Concentrate A mixed culture of moderately thermophilic microorganisms was used to bioleach chalcopyrite concentrate in a stirred tank reactor. The results show that up to 84.7 per cent of copper extraction could be achieved in 24 days at a pulp density of 6 per cent. The leaching rate of chalcopyrite concentrate tended to increase with an increase of dissolved total iron concentration. Furthermore, the extracellular polymeric substance (EPS) on the surface of the chalcopyrite concentrate was extracted and analysed. EPS was extracted at the first, third, eighth, 16th and 24th day during bioleaching, which mainly consisted of proteins, lipids, sugars and ferric irons. After the eighth day the total amount of EPS remained relatively constant. However, the amount of ferric iron in the EPS decreased in a large scale. The ore residue analysis indicates that the decrease of ferric iron was mainly due to the formation of jarosite on the mineral surface.

Sep 13, 2010

By Charles R. Keyes

I. INTRODUCTION. FOR a period of several years, and in a large number of cases, the Metallurgical Laboratories of the New Mexico School of Mines were employed in umpire work. During this time many important local problems were solved. Against the results of careful chemical analyses of ores, assay-returns were often checked. In many cases the assay-methods of mine and custom-smelter were compared, and both often found faulty for the ore concerned. A wide range of ores was covered. Many of the chemical analyses and assays were made by Dr. F. C. Lincoln, Professor of Metallurgy, now of the Montana State School of Mines. A varied series of instructive assays was prepared by Prof. R. B. Brinsmade, now of the West Virginia State University. Single assays and given series of tests were undertaken by H. T. Goodjohn, now chief chemist to the Cia. Metalurgica de Torreon, Coahuila, Mexico; by H. J. Hubbard, now superintendent of the Butters Divisadero Mines, Jocoro,. San Salvador, C. A.; by E. D. Morton, now superintendent of the Arizona & Nevada Copper Mining Co., at Lunning, Nev. ; and by A. W. Edelen, now superintendent of the Angangueo Unit of the American Smelting & Refining Co., in Michoacan, Mexico. A critical comparison of assay-methods that were found to be followed in the case of certain gouge-ores mined in the Mimbres range in New Mexico, and about which there had been much controversy, was made by D. F. Riddell, then Acting Professor of Assaying, and now superintendent of the Providentia Mines Co. of Parral, in Chihuahua, Mexico. To him is due the credit of much that is contained in the following notes, which be has generously permitted -to be used in advance of the publication of the complete results.

Jul 1, 1911

By I. E. Wahn, E. A. Boutin

"The Manibridge Mill is unique in its treatment of relatively high grade nickel-copper ore because in the mill design are included one 10' diam. x 10' Maxwell cell, and three 12' diam. x 12' tank cells. These large cells are used as rougher-scavenger cells. Three 8' diam. x 8' tank cells as well are used for cleaning and recleaning of the tank cell concentrate.Flexibility of flow is the main criterion in the tank cell circuit. Targets from these cells are a high grade nickel-copper product with a minimum of talcose gangue.The operation of the tank cells has been encouraging and they have performed well with both low and high grade heads, yielding a high grade concentrate product.Manibridge Tank CellsDescription:The tank cells at Manibridge consist of one 10' x 10' Maxwell cell, three 12' x 12' tank cells, and three 8' x 8' tank cells. The four large cells are currently being used as rougher scavenger cells. The three small cells are used as cleaner cells.Both sets of tank cells consist of Denver steel tank and Super Agitator Mechanisms with steel beam super-structures. The agitator mechanism has a totally enclosed ball bearing spindle housing with a cold rolled steel shaft, and a stanclard standpipe with adjustable collar.The air rings for the tanks were fabricated by Nelson Machinery. Both large and small cells have injection rings with equally spaced air holes in the bottom centre line of the ring.Air is supplied to the tank cells by a Dresser Clark low pressure air blower.The following is a table of pertinent data on the tank cells:"

Jan 1, 1974

By D. R. Hack

Increased consumption of concrete in the Pacific Northwest has pushed aggregate resource development pressure from urban areas west of the Cascade Range to rural areas east of the Cascades. Some recent development has focused on barge and rail accessible off-reservation Indian allotments that are exempt from state and county regulations. These lands have their own unique set of challenges, especially when Federal and Tribal governments have conflicting goals and attitudes pertaining to resource development. This paper discusses issues of leasing, reclamation, Federal vs. Tribal authority, cultural resources, and the history of allotment.

Jan 1, 2002