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By William G. Fischer

This paper attempts to close the gap between extensive rock testing with field measurements and the mine operator's need for safe mine layouts and alternatives. It was found that many of the variables that influence mine geometry and worker safety are relatively unimportant while others are critical. The development of empirical relationships which tie the critical variables to the "safe useful life" of a trona mine layout and observations made in 140 production areas where the variables were researched over a fifteen year period are discussed. The concepts presented may have applicability in mine design for other bedded deposits.

Jan 1, 1984

By Jack Bedder, Nils Backeberg

"Native antimony metal is rare and antimony generally occurs together with gold, lead, copper and silver. There are more than 100 antimony minerals, although the sulfide mineral stibnite is the main economic mineral.Antimony enters the supply chain either as a result of mining (primary production) or recycling (secondary production). China has by far the largest antimony resources and is, as a result, the world’s center for antimony mine production. While China remains the leading primary producer, accounting for 69 percent (80.5 kt or 88,700 st) of the global 117.5 kt (129,000 st) in 2017, market consolidation and regulatory inspections across China leading to closures of facilities have caused a significant decrease in Chinese output from 115.8 kt (127,600 st) in 2015 (81 percent of global production).Tajikistan and Russia are the next largest producers of antimony after China, both ramping up production in recent years. Russia could significantly increase its supply of antimony if Polyus moves ahead with supplying 10-12 kt/a (11,000–13,200 stpy) of contained antimony from gold tailings. Australia and Bolivia are also significant mine producers outside China. The value of the different ores varies based on the metal content of the concentrates, with the most valuable gold-bearing ores sourced from Australia’s Costerfield Mine and the least valuable mercury-bearing ores sourced from the Anzob Mine in Tajikistan. On average, Bolivian and Russian ores trade at an intermediate value between those from Costerfield and Anzob. Nearly all of the rest-of-world production is exported to China, where the ores and concentrates are processed into antimony ingots and oxides.Antimony ingot production is not as widespread as is the case with antimony mine production, owing to the high levels of pollution that are associated with antimony smelting. It is for this reason that smelting has been largely confined to China and other Asian countries ,such as Vietnam and Myanmar, where environmental legislation has historically been less stringent. Tajikistan has become a growing producer of antimony ingot since 2014, coming from the commissioned metallurgical plant at the Anzob Mine.Antimony oxide production is undertaken on four continents with China being the biggest producer. There is also a considerable amount of oxide production in Europe (mainly Belgium and France), which relies on imported antimony metal feedstock, mostly from China.A new antimony project under construction by Strategic and Precious Metals Processing (SPMP) in Oman made progress in 2016 and 2017, and after producing first metal in April 2016 in test facilities, was set to be commissioned in the first quarter of 2018. Commissioning had been moved back to June 2018, with a potential ramp-up to 2-3 kt/a (2,200 to 3,300 stpy) of antimony metal by the end of 2018. SPMP is also reviewing producing antimony oxide as part of its flow sheet."

Jan 7, 2018

By G. B. Glass

In 1996, 92.5% or 233 Mt (257.4 million st) of coal produced in Wyoming came from the Wyodak coal zone in the eastern Powder River Coal Field. While the mined portions of the zone consist of one to three beds of coal with an aggregate thickness between 15 and 33.5 m (50 and 110 ft), the thickest expression is 61 m (200 ft). The delivered coal from this zone averages 0.33% sulfur, 5.12% ash, and 19.98 MJ/kg (8,590 Btu/lb). This coal zone occurs at or near the top of the Paleocene Fort Union Formation, which is overlain by the Eocene Wasatch Formation. There is also production from two coal beds in the lower portion of the Wasatch at the southern end of the basin. Production of coalbed methane derived from the Wyodak coal zone is currently an estimated 10.2 billion cu ft a year. This production is occurring just west and downdip from the coal mines and is increasing each year.

Jan 1, 1998

By Lee W. Saperstien

At the heart of the mining process are a number of basic and fundamental tasks whose regular and repeated performance constitute the mining cycle. As will be discussed presently, these tasks are the basic components of the mining system. Section 9, Production Operations, provides the mine designer and engineer with an understanding of these tasks and with sufficient design principles to allow this person to create an efficient mine system. This section is meant to be an introduction and adjunct to subsequent sections that describe specific mining systems. However, sufficient design information is included here for the independent design of mine systems that may not be described elsewhere or for subsequent verification of existing designs. For the purposes of this section, mining subsumes excavation; thus this material applies to any excavation process. Accordingly, this section is written in general enough terms to include both surface and underground mining. It may be used also for civil engineering excavations that often involve the same steps. Obviously, the actual procedures undertaken in any specific mining system will appear to be very different from those taken in any other system. This is certainly true when comparing surface with underground methods. Yet the fundamental principles are often the same. This segment is written to explicate the basics. Wherever appropriate, the section will suggest the differences between the application process to surface or to underground mining.

Jan 1, 2008

By S. Pastor, S. Hahn

"As the concept of autonomous haulage systems (AHS) moves from proto-types to production-ready applications, the operating performance of the haul road will become ‘mission critical’ to the overall success of autonomy in mining. Deterioration in road performance will require remediation, human intervention and significant, albeit temporary, changes to operating procedures, to accommodate road maintenance. With autonomous trucks comes the opportunity to reduce road formation and operating width, and therefore generating potentially significantly reductions in stripping ratios and improvements to mine economics, but only if the design of the road, and it’s associated deterioration rate, is predictable and manageable, based both on the materials used to construct the road and the maintenance interventions to be carried out on the road. This paper presents the assessment of a digital photogrammetric approach to the characterization of a mine haul road surfacing, or wearing course material. Design and maintenance parameters for these roads are currently determined from physical particle size distribution (PSD) assessments of ‘in-road’ material. However, this approach does not accommodate the need, nor leverage the benefits from, AHS. The digital imaging approach is assessed in this paper, using two standard digital analysis software tools, together with in-service mine haul road wearing course samples and images which are assessed to determine the applicability and reliability of the approach to deliver a real-time assessment of haul road surfacing conditions and thus to identify the road maintenance interventions required to address deterioration. INTRODUCTION Enhancements in mine road design, construction and management for the past 20 or more years has largely been focused on short-term tactical needs. These improvements have not been matched by advances in the fundamental technologies that underpin mine road design and management, and although the quality of mine roads have probably increased, many of fundamental and longer-term issues have yet to be addressed. With AHS’s evolving from prototype to production applications, any decision to implement these systems in a mine requires a thorough evaluation of impacts, not only operational improvements, but the inter-connectivity of this autonomy technology to other organizational processes. In developing an understanding, the full interactions that may affect autonomous truck behaviour due to changes in various sub-systems or external environments, haul road conditions and operating performance is a key consideration. This is as true in autonomous as well as in conventional mine truck-based hauling systems where the mine haul road network is a critical and vital component of the production process."

Jan 1, 2015

By R. B. Crookston

This paper presents the status and mining method chosen by each of the active underground oil shale projects in the united States today. Potential improvements in equipment and methods on the near-term horizon are discussed. The problems and potentials that lie in the long-term future of oil shale mining are examined in light of the demands which must be met by this developing technology.

Jan 1, 1981

By Thomas V. Falkie

In bygone days, the mineral engineer spent most of his/her time on the technical aspects of designing, building, and managing mineral operations. In the last few decades, mostly since the 1960s, increasing amounts of engineering man power and time are spent dealing with federal, state, and local government agencies, laws, and regulations. It is not possible to plan, design, build, or operate mines, mills, smelters, or even office buildings without detailed consideration of government regulations and permitting requirements dealing with environment, worker health and safety, etc. The four chapters of this section provide an overview of the social, legal, political, environmental, and health and safety aspects of mineral enterprise. The section sets the stage for the working engineer/geologist in industry, government, consulting, or academe and points the direction for more detailed study in each of these areas.

Jan 1, 2008

By C. A. Young

In-situ Fourier transform infrared/internal reflection spectroscopy (FT ?IR/IRS) has been extended to study oleate adsorption at a calcite surface. The birefringent and transmission limitations of calcite were overcome by using an appropriately designed optical setup and a near-infrared (NIR) spectrometer. An adsorption isotherm was determined at pH 9.2 and room temperature. Comparison with the fluorite/oleate adsorption isotherm determined by the same technique indicates that oleate abstraction by calcite can be as much as one order of magnitude larger than that by fluorite. Nevertheless, the hydrophobicity of the fluorite/oleate surface is greater for equivalent adsorption densities as indicated by contact angle measurements and flotation results. The monolayer region has been confirmed to be chemisorbed oleate at both calcite and fluorite surfaces. Furthermore, multichannel laser Raman spectroscopy (MLRS) showed that chemisorbed oleate at the fluorite surface undergoes a double-bond reaction with oxygen to form an epoxide/polyether complex. Such a reaction, however, could not be detected at the calcite surface. These phenomena are discussed in terms of the intrinsic surface properties of the mineral systems as well as the adsorption density and the cross-linking/polymerization reaction of the adsorbed oleate film.

Jan 1, 1993

By Paul B. Queneau

Formulation and commercial utilization of solid-waste incinerator slag by-product is the focus of this paper. Particular attention is given to iron aluminosilicate melts having compositions similar to that of nature's basalt The earth?s crust can be viewed as an environmental laboratory for predicting stability of various silicates; small-scale laboratory experiments are necessary to confirm findings there from. An ideal slag consumes flux additives at acceptable cost, is compatible with furnace refractory, flows readily from the furnace, and has physical properties suitable for its commercial utilization -all within the critical constraint that the slag is environmentally stable. Examples of successful solid waste slagging practice, including tonnage, utilization and pricing, are provided from metallurgical and waste treatment operations of North America. Western Europe and Japan.

Jan 1, 1991

By F. Mielli

Camera systems and video surveillance are usually associated with people and asset protection. However, they can be applied in a mine environment beyond conventional surveillance: For process monitoring, collision avoidance, sizing, flotation cells, conveying systems, blasting, objects and people tracking, thermal profile, and to automatically identify equipment that is missing parts,. Image and video solutions can be driven by better integration of powerful video analytics and cameras systems in automation tools such as process controllers and supervision systems.

Feb 27, 2013

By Donald W. Breck

Zeolites were first recognized as a new group of minerals by Cronstedt with the discovery of stilbite in 1756. The word zeolite was coined from the two Greek words meaning "to boil" and "a stone" because of the loss of water when heated in the mineralogist's blow pipe. (1) In 1845 it was discovered that certain soils have the power of retaining ammonium Salts. (2) These were the first ion exchange experiments. Later it was discovered that it was the hydrated silicates in the soil that produced this phenomenon and several years later a paper was published dealing with the action of dilute salt solutions on silicates which showed that this base exchange principal, which we now call cation exchange, is reversible. The quantitative cation exchange behavior of zeolite minerals, such as chabazite, was studied. As a result any aluminosilicate which exhibited the property of ion exchange was referred to as a "zeolite;" even today the term has been applied to clay minerals as well as synthetic organic ion exchange resins.

Jan 1, 1973

By T. Krichler

"Current mine control stations are either single-position systems with high engineering effort or all-in-a-box solutions with low integration possibilities of third-party devices. Above all, both approaches are cost-intensive and not feasible for small companies. This paper shall be an inspiration of how to enhance the productivity and monitoring of an existing mining system in a modular way by introducing a proven technique of the ongoing digital revolution: A Wi-Fi network based on the communication protocol OPC UA. The starter kit consists of a single-board computer, a WLAN access point and any electronic sensor. INTRODUCTION The majority of the European mining industry is run by small and medium deposits (Europe Geology, 2017). This is due to the fact that most ore mines in Europe are widely distributed within the continent, are generally small and additionally they are often steeply inclined. Such ore bodies are normally mined with underground mining methods and must be excavated with high selectivity because of their small thickness. That is why the economy of scales, higher efficiency through bigger machines, cannot be used in most deposits in Europe except for lignite mines. It is important to find an alternative possibility to improve the efficiency of European mines for making them competitive internationally. For cost optimization and profit maximization it is necessary to use the trends of industry 4.0 and to broadcast these into the mining industry to reach a technological advantage. The goals of the EU within the Horizon 2020 funded project are to shorten the actualisation of the mine and block model to hours, improve the communication with Through the Earth (TTE) via very- or ultra-low frequency for long-time monitoring of the abandoned workings, and develop a cost-effective mine control station for optimization of mining processes in Small and Medium Enterprises (SMEs) as well. This paper deals specifically with the new approach for data acquisition, transmission and visualisation of a mine. SCADA AND ERP IN MINING There are already many Supervisory Control and Data Acquisition (SCADA) and Enterprise Resource Planning (ERP) programs on the market, but these are normally not developed for the mining industry. At the moment this leads to three options. • To hire a system integrator, who shall build a complete control station for one mine that requires a high amount of knowledge in programming and cannot be maintained by the mining company itself. • To buy different types of out-of-the-box systems, whereby every system can include some of the used technology. In this case a huge amount of project engineers and operators – at least one per system and shift- is required. • To buy every machine and program from one company including the service contracts."

Jan 1, 2018

By William L. Young

There is an old saying in Canada: "Mines are made as much as discovered." What follows is Young's perception of his experience developing and financing the Cochrane Hill gold mine project. In 1974, I came back from rutile and zircon exploration and mining in Australia. I became interested in a copper, lead, and zinc project in the Bathurst District, New Brunswick. Much field work had already been done but I was convinced that a reinterpretation of the geophysical work left room to enlarge on the known mineralization. So, with my own money I put a property deal together, found an underwriter willing to raise $100,000, and had a lawyer produce a prospectus. The prospectus was ultimately accepted for filing by the Ontario Securities Commission and I acquired funding and began work. It did not take many drill holes to determine that the interpretation was not geologically valid. However, while drilling was going on, geophysical and geochemical explorations indicated interesting anomalous zones elsewhere on the property. But by now the base metal market climate had soured and the $50,000 I had left was not enough to evaluate the new results. So I decided to farm out the property. A data folio was produced and the property was optioned to a major mining company, with Northumberland Mines Ltd. retaining a 20% free, carried interest. By 1976, the market for junior issues was so bad no under¬writer would even talk to a geologist and I still had the $50,000 in the bank and was looking for something to initiate. A Project That Went Nowhere Market research indicated that the Toronto area imported fine calcium carbonate fillers from Georgia, Alabama, and Vermont. I was aware of the specs and the fact that there is a large marble belt in Eastern Ontario. After some prospecting, I found an interesting deposit. The product was slightly high in silica and low on brightness. Research work eliminated the silica and corrected the brightness. So, with insufficient money we launched a feasibility study. This included diamond drilling, bulk sampling, special fine grinding and air classification tests, and an in-depth market survey. Our product was as good or better than those on the market. Our advantage was that delivery could be made by a two-hour truck haul to the customer. The present system of rail delivery had many problems, especially in winter. Despite everything looking rosy, we ran into a stone wall. The underwriters were singularly unimpressed because the public saw little glamour in a substance most people had never heard of. The issue would have been difficult-if not impossible-to sell. Banks and government agencies took the position that if we could get long term take-or-pay contracts then they would lend the required capital. None of the suppliers, however, would even consider a contract until production had begun and they could evaluate the production material. It was a classic "catch 22" situation. I have gone into this in some detail to show how tough the industrial mineral market can be. We eventually optioned this calcium carbonate property to a major corporation. The option agreement would give us a free, carried 15% and the right to buy up to 40% for contributing 25% of the production costs. But the experience left my company in poor financial shape. To survive, I think the entrepreneur-geologist must always have at least one project in reserve, an emergency plan. I had been searching out a new project to work on, after the calcium carbonate option was wrapped up. It was gold. Gold intrigued me and I knew quite a bit about Nova Scotian gold. I felt that with any rise in price, many of the former high-grade gold mines would have interesting potential for the larger, low grade portions of the deposits. That is how I happened on Cochrane Hill, where much work had been done in the early 1970s when gold as $4.82/g ($150/ oz). This time my timing was good. No sooner had Northumberland signed an option agreement than gold prices started to rise. In six months, they went to $27.331g ($850/oz). Even so, financing gold prospects in early 1980 was still not easy. It had been years since gold financing had been undertaken. A whole new generation of investors, with no knowledge of gold mining, had grown up. So, with accounting and legal council, we decided on a semiprivate "seed money" offering. Under the new Ontario Securities Act, this was a new-and partly tax sheltered-concept. At the time, it was very innovative.

Jan 6, 1982

By J. C. Reid

Pre-cambrian scheelite deposits in Northeastern Brazil are widespread in a high grade metamorphic terrain. Previously these deposits had been interpreted as contact-metasomatic. In this paper, a volcanigenic model is invoked based on the volcanic setting (proximal to distal) and the absence of associated felsic intrusives and spatially associated metasomatic skarns. The tungsten was introduced into sediments by volcanic- exhalative processes and subsequently remobilized and further concentrated by heat and metamorphis fluids associated with high-grade metamorphism and migmitization. An alternative syngenetic - diagenetic model is discussed which requires the transport of tungsten by heteropoly acids and deposition of the tungsten as a function of Eh and Ph conditions and different clastic depositional environments. While such stratabound tungsten deposits are considered rare in North America, the hypotheses developed in this paper may open new areas for exploration.

Jan 1, 1983

Cement in 1975 indeed did operate in an unfriendly environment. World recession, escalating costs, fuel crises, reduced product demand . . . . all led to market conditions detrimental to industry profit margins and investment re turns. During the year plant utilizations fell, break-even points were raised, and competitive moves introduced to move built up inventory levels. A number of cement plants were temporarily taken out of production to help alleviate specific situations. Meanwhile, under resultant financial pressure, several companies omitted dividend payments, changed their top executives, and reorganized and reduced staff overheads. It was a difficult year for cement, yet a much more ominous note was sounded in permanent plant closings. Four more cement operations were shut down in 1975; to date in 1976 we know for sure of three additional plant closings, while rumour has it that at least one more may not be in production by year-end. The somber feature is found within the descriptions of the closed facilities, and in the stated reasons for their being taken out of cement manufacture.

Jan 1, 1976

By H. Gerry Stephenson, Devin Castendyk

"One of the most important environmental issues associated with contemporary openpit mining is the closure of mine pit lakes, and the perpetual legacy these lakes can potentially generate. Ideally, successful pit lake closure includes the following:• The water quality within the pit lake, plus surface water and ground water discharging from the pit lake, meets premining or other acceptable water quality conditions of the receiving environment. • The termination of all active treatment processes.• The return of the pit lake to the government for long-term care and maintenance.• The release of the mining company from all future liabilities associated with the pit lake.• The return of the environmental bond to the mining company.• The reuse of the pit lake for some post-closure, beneficial purpose.The achievement of these goals is known as walk away pit lake closure.Peer-reviewed publications of successful walk away, pit lake closure provide mining companies with the ability to address public concerns regarding the safety of pit lakes which commonly occur during the permitting, operations, and closure phases of mining. To date, most published work on walk away, pit lake closure work has occurred in the coal mining sector in Germany and Australia (McCullough et al., 2009; Jones and McCullough, 2011; Kumar et al., 2013; Schultz et al., 2013). In North America, examples of walk away, pit lake closure are not widely discussed in the literature despite there being excellent examples from the coal mining sector in Alberta, Canada (e.g. Pleasure Island, Black Diamond, East Pit, Sphynx, Robb, Lovette, Siltstone and Sterling), and from the iron mining sector in Minnesota in the United States (e.g. Portsmouth Lake, see MNDNR, 2018). Although seldom included in discussions of pit lakes from the metal and coal mining sectors, the aggregate and fabricated-stone mining sectors also produce pit lakes, and there are numerous examples throughout North America where these pit lakes have been successfully closed and transformed into post-mining resources (Vandenberg, 2018; Crossman, 2019). The difficulty of finding these good examples in the literature makes it challenging for companies to respond to public and regulatory questions regarding pit lake closure and reuse. As such, there is a pressing need to document the motivations and approaches used in examples of successful, walk away, pit lake closure in North America so that the mining industry, at large, can learn from these examples and can better address public concerns."

Aug 1, 2019

By Christopher J. Vise

Although production operations at mines, representing the extraction and removal of the mined material, often appear to receive the greatest amount of attention, the emphasis given to auxiliary operations is continually increasing. This is due to the changing economic, social, and environmental climate in which modern mines must operate. Auxiliary operations can best be described as those activities that are not directly related to the extraction and removal of the mined material, but must receive proper attention if recovery is to take place in a safe, efficient, and socially responsible manner. In fact, certain mining auxiliary operations, such as strata control and ventilation, are considered to be of such importance that they warrant separate sections in this Handbook. Judging from a mine-personnel standpoint, it is not uncommon for a mine to hire the same number or more individuals responsible for auxiliary operations as the number assigned to production.

Jan 1, 2008

By Guillermo P. Selas

Perhaps this is the first time that an analysis of the industrial minerals panorama has been made in Mexico for that type of commodities. Because the non-metallic minerals lack the glamour of the metallic minerals and are usually of less unit value than metallics, a comparative study of these commodities has seldom been attempted. Sulphur, fluorite, barite and few others are an exception. Consequently, the statistics on the lowest per unit value industrial minerals, such as limestone, dolomite, gravels, sands, etc., are usually scarce and not always accurate. The following, then, will be an attempt to show a general status of the industrial minerals in Mexico with due reservations regarding volumes and values. According to Kruger (1971), this group of minerals surprisingly very little known, and called non-metallics because the lack of metallic luster, is the largest group of the mineral kingdom. It constitutes perhaps 75% of all the mineral varieties. For the most part, these minerals are compounds of common acids, sulphides, hydroxides and two elements carbon and sulphur. The list of non-metallic minerals is therefore very long. It includes the borates, carbonates, chlorides, fluorides, nitrates, phosphates, silicates, sulphates and less commonly arsenates, chromates, molybdates, sulphides, tungstates and vanadates. The latter group and many of the oxides are sought usually for their metal content.

Jan 1, 1974

By P. C. Thakur

The productivity in coal mines, measured in terns of the output per manshift depends largely on the efficiency and speed of men and materials transport between working faces and the surface. The mechanization of coal winning and material handling processes has led to a great rise in the mine productivity (1). Early applications of power in U. S. coal mines were mainly electrical. The excellent traction available with the DC motor and the ease of the distribution of the DC power have made trolley wire installations for haulage very popular. In shallow mines with very limited emissions of methane it did not constitute a major hazard but as mine depths increased and corresponding emissions of methane also increased fire and methane ignition hazards have become very serious. Conveyors have proved economic where intense mechanization of coal faces generates a large output of coal from a single face, but the fire and respirable dust hazard associated with them are no less serious. Recognizing these shortcomings, the Federal Coal Mine Health and Safety Act of 1969 laid down numerous provisions for the safe use of trolley-wire haulage and conveyors (2) which generally improve safety but in some cases complicate mining operations and have decreased productivity significantly since 1969. In course of time as coal mines become deeper and hence gassier and as the emphasis on safety increases it would be inconceivable to use trolley-wire haulage under ground as already witnessed in several other countries with deep coal mines. With rising capital investments and cost of the protection against fire and respirable dust, the use of conveyors may also have to be limited to special areas, e.g. main entries. Indeed, there are only two alternatives available, namely; (1) Degasify the coal seams prior to mining and use conventional electrical power, or (2) Develop alternate sources of power which would be safer and yet efficient and cheap.

Jan 1, 1975

By Duluth Engineers' Club, Engineers' Club of Northern Minnesota

"Prospecting and Exploration. Since the Lake Superior ores occur in pockets or distinct bodies and vary much as to character and location, the actual mining of the ores is preceded by much work of an exploratory character. This work includes prospecting and exploration.Prospecting is the term generally applied to the quest for surface indications of ore, or the conditions which would warrant the expectation of finding ore in the vicinity. It includes such 'operations as geological examination, dip needle work, shallow test-pitting, and trenching. The ore bodies of the Mesabi Range are non-magnetic, and dip needle prospecting is therefore valueless. On the Cuyuna range, however, magnetic attraction as evidenced by the dip needle has been extensively employed as a guide to the location of ore deposits; in other localities it has found limited application.Drill Exploration. After the presence of an ore deposit is known or suspected, resort is generally had to exploration by means of diamond or churn drills. On the old ranges geological conditions generally make this manner of ascertaining the exact limits of an ore deposit impracticable; so, if two or three adjacent drill holes develop considerable depths of ore, the sinking of a shaft for underground exploration, development and mining is generally considered warranted. On the Mesabi Range, however, the flat-lying and comparatively shallow characteristics of the ore formation warrant much more extensive drill explorations. On this range, then, an ore body 'is almost invariably followed· out with the drills, and its limits are determined to the point where the complete plan of development can be worked out in advance of actual mining operations"

Jan 1, 1920