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By F. A. Camisani-Calzolari

The latter half of the 20th century has seen the proliferation of a series of codes to address commodity needs which were brought about by rapidly advancing technologies and the globalization of markets and consumerism. This paper addresses the specific needs and the origin of this surge and presents these codes in the context in which they were developed. It also compares the main codes or groups of codes and elaborates upon their strengths and weaknesses. Three main categories of codes are identified, namely codes for reporting to international agencies, codes addressing government needs and, finally, codes for the investors and the stock market. Codes governed by international agencies usually relate to strategic commodities which have highly specialized fields of usage such as nuclear power generation where international cooperationis eventually the only viable approach for both the development of technologies and their applications. Codes for reporting to governments address the necessity of each state to exploit its mineral potential profitably and to secure the preservation of wealth for future generations. Reporting to investors is experiencing a considerable popularity as of late because of globalization in mining and the growing need for outside financing of mining projects, whose capital requirements are getting out of reach for the average mid-cap mining company. All these codes have advantages and shortcomings dictated by the specific circumstances under which they were developed, therefore necessitating the definition and implementation of some kind of international standard whereby investments and the spread of information across political boundaries would be facilitated. Though none of these codes might ever become international in the true sense of the word because of significantly different legislations at national level, a step that would greatly contribute to the cross-border disclosure of information would be the reciprocal recognition of competent persons by the major mining countries, including China and Russia. It is also becoming essential that financial institutions and investors be properly advised on mining projects by reporting reserves and resources in a transparent and responsible way with the relevant public disclosures being compiled by professionals who take full responsibility for their submissions. Keywords: reporting codes, mineral resources, mineral reserves, competent person, UN Framework Classification, IAEA classification, JORC Code, SAMREC Code and CRIRSCO.

Jan 1, 2004

By Maxwell Gensamer

Jan 1, 1960

By C Rizzardi, M Callahan, J Mahon

Henderson Operation’s underground molybdenum mine has been in production since 1976. Since that historic date, more than one billion pounds of moly has been produced, and over 120 Mt of ore extracted from three different levels and many different panels. The safe and successful operation of Henderson has been, and will continue to be, dependent on utilising an increasingly sophisticated fleet of equipment, advanced designs, innovative mining techniques, best practices in maintenance processes, improvements in crushing and conveying systems, and most importantly, the training and mentoring of the underground staff. These ‘professional mining technicians’ have been essential in the safe and efficient operation and maintenance of the underground mine and convey systems, and will drive the continuous improvements needed to keep Henderson competitive in the growing global market.CITATION:Callahan, M, Mahon, J and Rizzardi, C, 2016. Development of the professional mining technician – Henderson’s underground mine continuous improvement program, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 161–166 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

By J. -W. Kim, Y. -B. Kang, H. -G. Lee

The effect of SiO2addition on the decomposition of Li2CO3was investigated at temperatures up to 1000ºC. It was found that addition of SiO2greatly enhanced the decomposition of Li2CO3. The main decomposition reaction started at around 600ºC, and completed just above the melting point of Li2CO3. The major decomposition product was Li2O?SiO2irrespective of the Li2CO3to SiO2mixing ratio while both reactants were available. It was ascertained that a liquid layer betweenLi2CO3and SiO2particles formed and facilitated the decomposition reaction. The governing reaction of the decomposition was the one between the dissolved Li2CO3and SiO2in the liquid layer to form Li2O?SiO2. The decomposition rate was independent of the Li2CO3/SiO2mixingratio until either one had been completely exhausted. When excess Li2CO3existed, it further reacted with the initial product of Li2O?SiO2to form 2Li2O?SiO2. When SiO2was found in excess, on the other hand, no further reaction took place. This is attributed to the fact that uponLi2CO3exhaustion there is no liquid phase available to facilitate further reaction. The apparent activation energy of the decomposition of Li2CO3in existence with SiO2is 198 kJ mol-1.

Jan 1, 2004

Council for 2004/2005 President F.M.G. Egerton President-elect W.H. van Niekerk Vice-presidents Senior R.P.H. Willis Junior R.G.B. Pickering Immediate Past-president T.R. Stacey Honorary Treasurer J.A. Cruise

Jan 1, 2005

By F. M. Vokes, P. M. Ihlen

Paper presented at Mineralisation in the Caledonides, the Mike Gallagher memorial meeting held in Edinburgh, 27-28 June 1996. Ore deposition was related to three major stages: continental rifting and separation (Vendian-Late Cambrian), convergence (Late Cambrian-Early Silurian) and collision (Early Silurian-Devonian). The first stage included deposition of volcanogenic massive sulphide Zn-Cu and stratabound or stratiform Fe and Zn-Pb(-Cu) on continental margins, as well as less economic Nb and Fe in carbonatites, U, Mo, Ni and V in Alum Shales and orthomagmatic Cr, Fe-Ti and Ni(-Cu). The numerous volcanogenic massive sulphides formed during convergence included Early Ordovician Cu-Zn, mature-arc Cu, Zn, Pb and Fe-oxide deposits, Besshi-type deposits dominated by Cu or Zn in gabbro-intruded sediments and minor Cu-Ni(-PGE), Cu-Mo and skarn deposits. The collisional stage is represented by epigenetic deposits including sandstone Pb deposits (Pb, Zn, Ba, F and Cu) and minor vein deposits with variable Au, Ag, Pb, Cu, Zn, Fe, As, Sb, W and Mo

Jun 19, 1905

By J. F. Lupo

Leaching operations combine both metallurgical and hydraulic processes to extract metals from the ore heap. In the design of leaching operations, metallurgical tests and simple hydraulic tests are often conducted to define operational parameters such as leach cycle time, application rate, lift height, and effective leach area. While metallurgical constraints are often the primary focus on leach facility design, the hydraulic factors are also critical to the overall success of the operation. Some of the hydraulic factors that are known to impact solution flow through heaps include: • Ore physical and hydraulic properties, • Variation in ore properties under heap loading, • Ore mineralogy and its susceptibility to chemical and/or mechanical degradation, and • Heterogeneities within the heap. This paper presents a discussion on hydraulic factors that may impact the effectiveness of leaching operations. In addition, methods are presented which may be used to assess flow conditions within active and inactive heaps.

Jan 1, 2000

By Dean H. Ambrose

This paper presents the results of a study using computer human modeling to examine machine appendage speed. The objective was to determine the impact of roof bolter machine appendage speed on the likelihood of the operator coming in contact with. A contact means two or more objects intersecting or touching each other, e.g., appendage makes contact with the operator?s hand, arm, head or leg. Incident investigation reports do not usually contain enough information to aid in studying this problem and laboratory experiments with human subjects are also not feasible because of safety and ethical issues. As an alternative, researchers developed a computer model approach as the primary means to gather data. By simulating an operator?s random behavior and machine?s appendage velocity, researchers can study potential hazards of tasks where it is not possible to perform experiments with human subjects. Analysis information is helpful to the mining industry in terms of making recommendations that reduce the likelihood that roof-bolter operators experience injury due to contact with a moving boom. Data analysis of roof bolter simulations show that the virtual-operator?s response time has little effect on the number of contacts experienced. Based on frequency and cross-tabulation, regardless of other variables, contact incidents were always greater when the boom was moving up, were always greater on the palm, and were always greater for the boom part of the machine. Also, regardless of boom speed, the 25th-percentile-sized operators experienced more contacts than did other operator sizes. Furthermore, regardless of boom speed, the 152-cm mine seam experienced more contacts than did other seam heights tested. Results of a survival analytic approach suggest that controlling the boom speed is the most important factor in determining the risk of an operator making contact. Based on the data collected, boom speed greater than 41 cm/s results in a substantial increase in risk to the roof bolter operator and should probably be avoided. At speeds less than or equal to 25 cm/s are associated with a more modest relative risk, which represents an acceptable level of risk. Also, at speeds between 25 and 41 cm/s, there could be a particular boom speed in this range at which a significant inflection point in the relative risk estimates occurs. Based on the results, this issue needs to be addressed by future research.

Jan 1, 2003

By Martin H. Rogoff

This publication combines a critical review of the literature on the microbiology of coal with an introduction to those areas of microbiology related to studies of coal as a biological material. The attack on coal by microorganisms as yet remains doubtful. Only the low-rank coals contain an indigenous microbial flora, and even these organisms are not peculiar to coal, but are common soil and water forms. No experimental data have as yet been presented, either in the literature or in the present work, which unequivocally demonstrate the oxidation of coal by microorganisms. Reasons for the resistance of coal to such attack, including insolubility, physicochemical structure, steric hindrance of enzyme action, and the presence of antibiotic materials in coal are discussed. Microorganisms do attack large aromatic molecules and the mode of oxidation of aromatic ring systems by bacteria is presented. Well-defined pathways are known for the oxidation of polycyclic compounds with one to three rings, and these paths with their key intermediates are described and related to the possible oxidation of coal.

Jan 1, 1962

By Kevin Landey, Eric Gerst

Expanding blast patterns to near the limit of an explosives’ ability to do the necessary amount of work is a common practice to reduce drilling and blasting costs. Choosing less expensive explosives such as ANFO vs. emulsion, bulk product versus packaged product, etc. are also common cost savers. Both practices are only effective as long as the pattern geometries are accurately drilled. However, will pushing the limits on pattern sizes and explosive products produce consistent results at the face, minimize oversize, produce superior fragmentation, and improve crusher throughput? Sometimes, but no amount of explosives can overcome a poorly drilled pattern. Knowing the probable outcome of any changes in drilling and blasting is valuable in achieving success.

Jan 1, 2018

By Peter Townsend, Sergei Diachenko, Allan Moss

The Palabora Mining Company has successfully extended the life of its operation by developing a 30,000tpd block cave underground mine below the now closed open pit. The process of transitioning from surface to underground mining has been technically, operationally and managerially challenging. This has been due to a number of factors; in particular, the development of a block cave in a very competent rock mass. The competence of the rock mass is clearly demonstrated in the open pit that preceded the block cave, one of the steepest deep open pit excavations in the world. With cave breakthrough, however, the pit was ?instantaneously? deepened by 400m causing a major failure of the northwest wall involving close to 100Mt of waste material.

Jan 1, 2006

By C. T. Baroch

CESIUM-137 ISOTOPE began to displace cobalt-60 III the treatment of cancer during 1956. Production and Consumption.-Consumption of cesium and rubidium was approximately the same as in 1955. Production, however, decreased, as several companies shipped from stocks produced in previous years. South Africa was the source of most cesium and rubidium minerals used in the United States in 1956. Cesium and rubidium metals and compounds were produced from ore by: DeRewal International Rare Metals Co., Philadelphia, Pa.; Fairmont Chemical Co., Inc., Newark, N. J.; Foote Mineral Co., Philadelphia, Pa.; and Rocky Mountain Research, Inc., Denver, Colo. Most sales were to domestic consumers, but small quantities were exported to Australia, England, Germany, and Sweden. New production facilities were under construction in. 1956 by San Antonio Chemicals to produce mixed potassium, rubidium, and cesium carbonates. A plant capable of separating and packaging 200,000 curies of cesium-137 annually was under construction at Oak Ridge National Laboratory.6

Jan 1, 1958

Open pit mine plans define the complex strategy of displacement of ore and waste over the mine life. Various mixed integer linear programming (MILP) formulations have been used for production scheduling of open pit mines. The main problem with these models is the inability to solve real size mining problems. We present a mixed integer linear programming formulation for the open pit long-term production scheduling problem. To reduce the number of binary integer variables in the formulation, we aggregate blocks into larger units referred to as mining-cuts. We present a semi-supervised clustering algorithm which aggregates smaller blocks based on rock types and grade ranges into mining-cuts without introducing an error in the grade estimated values. The cluster-based aggregation algorithm is fully integrated into an MILP mine production scheduling prototype software. We have implemented, verified, and validated our models. The efficiency of the new platform is evaluated through iron ore mine case study.

Dec 6, 2010

By Sidney Katell

This report, covering the period January 1969 through December 1969, is a continuation of a series that began with the publication of Information Circular 7516 in October 1949. It is the 11th in a series of reports prepared in cooperation with the American Association of Cost Engineers. The abstracted articles are concerned with all phases of cost engineering in the field of chemical and petroleum plants and related subjects. They are from the following sources: 1. American Association of Cost. Engineers Bulletin. 2. Bureau of Mines Information Circulars. 3. Bureau of Mines Reports of Investigations. 4. Chemical Engineering. 5. Chemical Engineering Progress. 6. Chemical Week. 7. Coal Age. 8. Coal Mining and Processing.

Jan 1, 1970

By C. Stoneback

The attapulgite industry saw a year of solid growth after a weaker 2003. Demand was up between 5 percent and 6 percent driven by almost all of the key markets. Construction continued to show record new housing demand, assisted by continued low interest rates. That drove strong growth in construction related markets like coatings, tape joint compounds and other construction materials applications. The agricultural markets rebounded modestly to increase sales for suspension fertilizers, animal feeds and pesticide carriers. Oil drilling also showed strong growth due to high oil and gas prices. Sales to molecular sieve applications grew due to petrochemical and construction demand. The export markets were assisted by further depreciation of the dollar. The only weak area was in nonagricultural granular sorbents, where other sorbent materials continued to dominate.

Jan 1, 2005

By Steven J. Page, Andrew B. Cecala, John A. Organiscak

In This Chapter [Drill dust control: wet and dry Enclosed cabs on drills and mobile equipment Haul road dust control] Overburden drilling generates most of the respirable dust that affects workers at surface mines. Both wet and dry methods are available to reduce this drill dust. Overburden removal by mobile excavation equipment such as bulldozers, front-end loaders, and haulage trucks can be dusty, particularly under dry and windy conditions. Tightly enclosed cabs with dust filtration systems can substantially lower the dust exposure of both drill and mobile equipment operators. Haul road dust control can be achieved by water application or chemical application. DRILL DUST CONTROL [Drill dust is controlled with wet or dry systems. Wet systems can be more efficient, but may freeze in the winter. Dry systems require careful maintenance of the drill deck shroud. An improved deck shroud is shown.] Wet Suppression. Wet drilling systems pump water into the bailing air from a water tank mounted on the drill. The water droplets in the bailing air trap dust particles as they travel up the annular space of the drilled hole, thus controlling dust as the air bails the cuttings from the hole [Page 1991]. In wet drilling systems, typical water flow rates are 0.1 to 2.0 gpm depending on the size and type of drill and the moisture level of the overburden. The drill operator controls the flow using a control valve located in the cab. Some drills are equipped with a flow meter to give the opera-tor a visual sign of the flow rate. Raising the water flow will improve dust capture, but too much water causes operational problems. Because of this, the drill operator must exercise care in find-ing the best water flow rate.

Jan 6, 2003

By Sam S. Taylor

Subsurface disposal of oil-field brines was practiced in Oklahoma on a limited scale as early as 1925. The technique of subsurface injection has been improved immensely and has been applied with varying success in many oil-producing areas in Oklahoma, and elsewhere. This method of disposal, however, is only one of several methods available to operators of oil-producing properties, but, in contrast with usual methods of handling brines on the surface it eliminates the damaging effect of mineralized water on fresh-water supplies, vegetation, and aquatic and other animal life. Other methods of brine disposal approved by regulatory agencies in some States include (1) impounding in impervious ponds and solar evaporation, (2) controlled diversion into surface waters, and (3) recovery of the mineral salts of the brine. In most, States where oil is produced regulatory bodies authorize the use of one or more of these methods of brine disposal. In Oklahoma, for example, the Oklahoma Planning and Resources Board of the Conservation Commission has been authorized to adopt whatever methods or means may be necessary to prevent contamination by mineralization of all potable waters within the State.

Jan 1, 1942

By R. L. Kidd, T. H. Miller

"INTRODUCTION This paper is the seventh of a series of yearly reviews started in 1921 and pre¬sents information gathered in a cooperative investigation undertaken by the United States Bureau of Mines and the University of Utah. It is the purpose of this report to make available flotation—reagent consumption data and other milling information in such a manner as to be of value to the milling industry and to the manufacturer of flotation reagents.These data have been compiled from a survey of about 300 concentration plants in the United States. Much additional information has been obtained from the various offices of the United States Bureau of Mines. Many of the plants covered in the survey made complete reports of their operations, but others were apparently unable to supply this information in sufficient detail to meet the requirements of this report. As a result, some sections of the report are more complete than others. In general, however, the mill reports were much more complete than in previous years, and for the first time it has been possible to calculate average mill recoveries in the treatment of certain classes of ores. As in the past, every effort has been made to conceal individual plant operations.ACKNOWLEDGMENTSIt is realized that the publication of this information is possible only through the assistance of the mill operators, and the authors wish to express their appreciation of this cooperation. Thanks are also due the various field offices of the United States Bureau of Mines, division of mineral statistics, for assistance in collecting this information."

Aug 1, 1931

By M. Kuchta, A. Newman

LKAB’s Kiruna Mine, located above the Arctic Circle in northern Sweden, is the second-largest underground mine in the world today. The orebody is a world-class high-grade magnetite deposit, from which three raw ore products are extracted. We use mixed integer programming to determine a production schedule, i.e., which production blocks to mine, and when to start mining them, so as to minimize deviation from planned production quantities while adhering to the operational constraints of the mine. The resulting model contains thousands of binary variables and a commensurate number of constraints, precluding us from obtaining a schedule in a reasonable amount of time. We describe a method that builds on prior, related work, to expedite solution time. Keywords: underground mining, production planning, optimization, integer programming

Jan 1, 2003

By Carlie E. Banks

Tasks during Phase I of this contract effort were performed in four principal functional areas. These were geology, hydrology, reclamation and mining. Data were gathered from literature reviews, mine visits, survey of manufacturers, consultation with government agencies, and unpublished or private communications with contractors and consultants. The data collected were analyzed for omissions or inaccuracies, then organized into tables, graphs and flow charts to provide a concise body of technical and cost data suitable for the engineering analyses required in Phase II of this contract. Maps illustrating estimated grade and thickness of the oil shale were prepared, some of which are included as exhibits to this report. A preliminary mine layout was performed to test the completeness of the collected data.

Jan 1, 1975