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By Raúl Prebisch

Continuando con el análisis de la realidad latinoamericana, el presente texto señala los factores estructurales internos de la insuficiencia dinámica de desarrollo latinoamericano como la absorción productiva de mano de obra, el aumento de productividad y necesidad de nuevas inversiones, los motivos principales de la insuficiencia dinámica, acumulación de capital, el obstáculo de la tierra, el funcionamiento de la estructura social, la inflación y la estructura social, los tipos de capital extranjero y la planificación y funcionamiento del sistema económico.

May 1, 1964

By Rodolfo Espinosa Gómez

"Industrias Peñoles, S.A. de C.V. – Mining Division, has initiated in the last ten years, six Mining Operations (Bismark, Tizapa, Ciénega, La Herradura, Rey de Plata, and Francisco I. Madero) and it has expanded several of their existing Operations (Sabinas, Fresnillo, Tizapa, Ciénega) one or more times.This work aims to share the experiences learned on this growing process. Some of these lessons are: 1) Project leaders must have a leadership that fosters good communication and team work; and this leadership style must come from top management. 2) A good communication must exist between the personnel from Engineering, Construction, and Operation. Also, this good communication must come from top management. 3) Starting the project with a solid Engineering Study. 4) Do not misunderstand cost with cost/benefit; always look at the cost/benefit. 5) Selecting good Contractors and good Suppliers. 6) Good training before the project commissioning is essential to reduce the learning curve period, this is even more important in areas where local people do not have any background in mining activities. 7) Recognizing that any project has a learning curve and it must be reflected on the production budget. 8) Avoid an over optimistic Mine preparation time schedule.BACKGROUNDIndustrias Peñoles S.A. de C.V.The mission of Industrias Peñoles, S.A. de C.V. (Peñoles) is to add value to non-renewable natural resources in a sustainable manner. Peñoles seeks to build long-term shareholder value; provide their customers with the highest quality products and services; maintain productive longterm relationship with their suppliers; develop and promote the capabilities of their personnel; foster mutually beneficial relationship with the communities in which it operates, and preserve the environment.Peñoles was established on 1887. It is a Mining Group with integrated Mining, Smelting and Refining operations of non-ferrous metals, and also produces inorganic chemistry materials. Peñoles is the main World producer of refined silver, metal bismuth, and sodium sulphate; Latin American leader in the production of refined gold, lead, and zinc.The Mining Group is made-up of nine mining operations producing concentrates with high gold, silver, lead, zinc, and copper contents. It produced in 2002, 365,900 ounces of gold; 52.7 million ounces of silver; 86,820 tonnes of lead; 266,000 tonnes of zinc, 11,840 tonnes of copper; with a total values of 3,780.6 million of Mexican pesos (~ $ 378.0 million U.S. Dollars)."

Jan 1, 2004

By H. L. Monro

Contribution by B. K. Martust I congratulate the author on his interesting paper. In my view, the establishment of the level at which South African gold output is at some kind of optimum is an interesting though somewhat academic exercise. Contribution by D. M. Hawkins* The thesis of the paper is a very interesting one, but, before it is used as the basis of any firm proposals to restructure the mining industry, which changes may be irreversible, one should be very sure that the basis of the calculations is sound. Contribution by P. J. Niewenhuizen* The hypothesis advanced by Mr Monro that the demonetization of gold in August 1971 introduced a major new policy variable, namely the supply-pricejdemand-price relationships, into the decision making process touches on a matter that has never really been given serious thought by the industry. Contribution by B. G. Kingsman* As a co-worker on the development of an econometric model for supply and demand in the world gold market with Mr H. L. Monro, it would perhaps be useful for me to make some comments on the various points raised in the discussions on his paper.

Jan 1, 1984

By G Hall

BHP BillitonÆs (BHPB) Yandi ore deposit is a channel iron deposit (CID) in the Pilbara district of WA. The ore is predominantly a goethite-hematite pisolite and overlays a clay at the base of the deposit. Knowledge of the location of the contact prior to mining is critical to maximise ore extraction and minimise contamination from and mining of the underlying clays which contain high levels of alumina. The contact between the iron ore and the clay is highly irregular. Traditionally the contact has been delineated by closely spaced drilling û this can be expensive and since each drill hole only provides a point sample measurement, irregularities in the contact surface can be missed. In September 2001, three high resolution geophysical techniques were trialled to see if they could be used to improve the efficiency and accuracy of ore delineation. The three techniques were resistivity imaging, ground penetrating radar and electromagnetic conductivity imaging. The resistivity data showed a favourable correlation with the available ground truth data from drilling. Using this ground truth data as a calibration, an interpretation of the depth to the base of the channel iron deposit (CID) ore was constructed for the areas surveyed. A significant attribute of the method is that the position of the base of the ore is imaged continuously along the lines that are surveyed rather than at discrete points. No continuous well defined ground penetrating radar (GPR) reflections were observed from the base of the CID ore. There did appear to be some correlation between the range of echo times that reflections were observed and the drill data, however the precision to which the range of echo times could be estimated was of the order of several metres and therefore not adequate to replace current procedures. The electromagnetic data showed good correlations with the existence of shallow clays but did not discriminate between variations in CID ore depth. This technique is therefore not suitable for mapping the base of the CID ore but may still be useful as a rapid tool for mapping the position of clay bands.

Jan 1, 2002

By Piotr Mertuszka

Many years of research on more effective and safer explosives have led to the development of emulsion explosives. They are the second most commonly used group of explosives worldwide, primarily because they are good alternatives to ANFO or dynamites. Their key advantage in underground applications is the lower content of toxic fumes in the detonation products. Emulsions are also characterized by high detonation velocity, high water resistance, low critical diameter, and mechanical loading capacity. Several factors affect the behavior of emulsion explosives. These factors are related to both manufacturing and applied mining methods. The most important factors include the charge diameter, type of sensitizer, density, hydrostatic pressure, ambient and charge temperatures, as well as the time elapsed between the charging of the explosive into the blast hole and its detonation. The selection of the type of explosive is based on the analysis of a number of parameters, including the density, critical diameter, volume of the post-blast fumes, detonation pressure, velocity of detonation, and sensitivity to external energy sources. In most cases, the conditions under which explosives are used differ significantly from those defined in standards. Such conditions cover, among others, the temperature of the rock mass and surroundings, humidity, rock strength parameters and the diameter of the blast holes. Consequently, the parameters of the explosives provided by the manufacturers may not correlate with those specified in-situ. Thus, within the framework of this study, the effects of the selected technological parameters on the detonation velocity of bulk emulsion explosives are presented. The analysis focused primarily on the factors directly influenced by the mine blasting services. The detonation velocity measured using the continuous wire resistance technique was used as the evaluation criterion. For this purpose, several underground in-situ tests were conducted, including the impact of the blast hole diameter, density, initiation method, sleeping time, and temperature on the detonation velocity. The results of in-situ tests have shown that the detonation velocity of bulk emulsion explosives depends strongly on the above factors, which may directly affect the effectiveness of blasting operations.

Jan 26, 2026

By E. H. Burroughs, M. J. Gavin

The references in the following compilation are selected chiefly from the literature of the years 1915-1920 , though a few of the more valuable standard works published before that period have necessarily been included . References to many articles have been omitted purposely , because the material covered by them is duplicated in publications included in the bibliography . It is manifestly impossible for the Bureau of Mines either to recommend or adversely criticize the statements of the various writers , particularly as to cost and profit estimates in articles referring to American shales , but it is hoped that the investigator will use caution in considering such statements , as it is well known that much of the literature on this subject has been published for promotion purposes and is therefore over- enthusiastic . Bearing this fact in mind , the reader should be able to judge for himself the reliability or usefulness of these articles .

Sep 1, 1921

By F. B. Plummer

PETROLEUM ENGINEERING deals with the production, transportation, and refining of crude oil. Refining is chiefly the work of the chemical engineer; production, that of the petroleum engineer. Production engineering only is discussed in this paper. Petroleum production engineering is closest related to and, in fact, is a branch of mining engineering. Formerly, many petroleum engineers were trained as mining engineers or mining geologists. The profession is related also to mechanical and civil engineering to about the same extent that mining engineering is. Petroleum production draws upon the mechanical branch for drilling and pumping machinery and upon civil engineering for the construction of transportation lines, water supplies, and water-disposal plants. Fundamentally, petroleum production engineering deals with the removal of the oil from the reservoir rocks, just as mining is concerned with the removal of ore. The process of oil production demands a specialized knowledge just as distinct from mechanical and civil engineering as mining is distinct from operating a Diesel engine. Even though the chief tools of the petroleum engineer are the drill and the pump, these may be of little avail, and certainly not efficient, if their selection and use is not based on a knowledge of the physical chemistry of oil, the geology of the formations, the structure of the oil sand, the hydrodynamics of the reservoir, and the interrelation of all these many factors.

Jan 1, 1936

By Joshua Cole, Joshua Sovechles, Christian Cardoso, Guillermo Bermudez, Martta Hirsi, Joshua Dettamanti, Rabia Abbasi

The implementation of technological advancements in flotation is key to optimize performance in mining operations. Consequently, flotation cell’s performance is highly dependent on the effectiveness of the mixing mechanism. A more efficient flotation mixing mechanism is likely to improve metallurgical performance and optimize energy consumption, which is the motivation for Metso’s journey to develop the latest iteration of FloatForce®. Looking to test the new design at plant scale, Metso approached the Kennecott Copperton concentrator, which is continuously looking for different venues to improve metallurgical performance. In this context, a test campaign was conducted to implement this new flotation mixing mechanism in their rougher circuit during 2024. The industrial trial consisted of several sampling campaigns assessing different operational parameters for comparison purposes around a 300m3 flotation cell. The effect of the new flotation mixing mechanism on the cell’s power draw was also studied. The results of this trial at Kennecott are presented in this paper. Overall new flotation mixing mechanism, FloatForce+ was seen to perform as well as the original FloatForce.

Feb 1, 2025

By H Arvidson, V Chamberlain, R Marinho, B Parsons, T Rowl, M Noppé, M Mattera

With the introduction of CRIRSCO (2019) based mineral asset disclosure, Regulation S-K part 1300, 2019 (S-K1300) by the United States (US) Securities and Exchange Commission (SEC), applicable to companies listed on the New York Stock Exchange from 2021, Mineral Resource is now required to be reported Exclusive of Mineral Reserve, referred to here as ‘Exclusive Mineral Resource’ (EMR). EMR is equivalent to reporting Mineral Resource additional to Mineral Reserve, which has been permitted in jurisdictions outside the US for many years. Despite this, there are no practical guidelines in the literature or relevant reporting codes and rules for Competent/Qualified Persons to refer to, which creates a risk that disclosure of EMR estimates across the industry will be inconsistent and potentially ambiguous for analysts, investors, potential investors, and other stakeholders.With the introduction of CRIRSCO (2019) based mineral asset disclosure, Regulation S-K part 1300, 2019 (S-K1300) by the United States (US) Securities and Exchange Commission (SEC), applicable to companies listed on the New York Stock Exchange from 2021, Mineral Resource is now required to be reported Exclusive of Mineral Reserve, referred to here as ‘Exclusive Mineral Resource’ (EMR). EMR is equivalent to reporting Mineral Resource additional to Mineral Reserve, which has been permitted in jurisdictions outside the US for many years. Despite this, there are no practical guidelines in the literature or relevant reporting codes and rules for Competent/Qualified Persons to refer to, which creates a risk that disclosure of EMR estimates across the industry will be inconsistent and potentially ambiguous for analysts, investors, potential investors, and other stakeholders.

May 24, 2023

By D. Pennington

Ground-water levels and subsidence have been monitored over a longwall panel of a deep coal mining operation located in western Pennsylvania. The monitoring network includes eleven ground-water monitoring wells completed to measure water level changes in separate shallow and deep aquifer zone-, and 50-foot surveyed subsidence stations parallel and perpendicular to the panel centerline. Monthly monitoring data were collected during the premining, mining, and postmining tine periods. Aquifer testing and borehole geophysical logging were conducted during premining, and post-mining conditions to document any changes in aquifer properties and ground-water flow patterns. Results indicate ground-water declines were located with respect to the mining face and mined longwall panel. Dewatering of the deep aquifer zone caused a significant water level decline in deep wells; however, the shallow aquifer zone was isolated fro major impacts by an aquitardal layer during, the, one-year period. Transmissivity data were greatly impacted by fracturing, in the highly anisotropic aquifer system. Borehole geophysical logging indicated changes in ground-water flow patterns and zones of increased fracturing from subsidence.

Jan 1, 1984

By H. R. Babitzke

The purpose of this Bureau of Mine- investigation was to develop columbium and tantalum alloys suitable or u at elevated temperatures. Columbium and tantalum were combined with tungsten, hafnium, zirconium, molybdenum, vanadium, and titanium, and the resulting alloys were evaluated with respect to workability, hardness, electrical resistivity, strength at elevated temperatures, oxidation resistance, and weldability. Cb-33Hf-10W-10Ti, Cb-20111-5Mo, and Cb-30Hf-5Mo exhibited superior high temperature properties. Cb-33Hf-10W-10Ti had tensile strength values of 44,300 psi at 1,200° C and 16,500 psi at 1,400° C, Cb-20Hf-5Mo had values of 35,700 and 20,700 psi, respectively. The corresponding values for Cb-30Hf-5Mo were 38,900 and 17,800 psi. These alloys are fabricable by conventional methods with excellent strength at temperatures up to and including 1,400° C. An oxidation rate of 7 to 21 mg/cm2/hr was observed up to 1,000° C.

Jan 1, 1967

By Myron Read

DURING the past 25 years, mining engineers have seen the development of a multitude of specialized engineering curricula in the mineral industry field. Bachelor degrees are now !ranted in the fields of mineral dressing petroleum engineering, geological engineering, fuel technology, and many others. These fields were all, previously considered to be part of a mining enginieer's work and elementary phases of them were included in mining engineering curricula. Their emergence has left some mining engineers with the fear that nothing will he left for a purely mining engineer to teach, or that mining engineering graduates will be unable to complete in any of these fields with the more specialized students and thus will have neatly restricted employment opportunies. A secondary reaction has been that if students who began to say that the pining engineering curriculum taught everything but mining, since so many of :he subjects that had always been udedAuded in the mining engineering curriculum now were fields in their own right.

Jan 1, 1946

By P. Myllykoski, J. Nylander, A. S. Korhonen, J. Larkiola

The coefficient of friction and the deformation resistance have been determined from the measured rolling parameters by applying the Bland-Ford-Ellis rolling force model and the artificial neural network model (ANN). The dependence of friction on the parameters such as reduction, rolling speed, front and back tensions, contact pressure and deformation resistance have been studied by the ANN model. Measured data of over 10 000 coils have been used in the training stage. Various dependencies have been examined and the results show that the friction coefficient does not depend much on the rolling speed. The reduction and deformation resistance seem to have the strongest effect on the friction coefficient. A friction model based on neural computing has been included into the existing rolling force model.

Jan 1, 1994

By J. W. Paul

This report is one of a series of papers on coal mining methods and costs which are being prepared through the sponsorship of the U. S. Bureau of Mines for the purpose of bringing to the industry a knowledge of methods as they are used at the present time, and data on certain features which govern costs, safety, and conservation. The methods employed are, influenced by local conditions with respect to the character and dip of the coal, the nature of the, roof and the thickness of the overburden, and the means employed for roof support and its control.

Jan 1, 1929

By P Cesare, S Munro, D Wandel, R A. Bearman

Consideration of the processing plant operational envelope is a key factor in production scheduling,and therefore mine planning, for any mining operation. In many cases hard-wired or regressionbased tonnage-grade-recovery relationships are used as mine planning constraints and as a means of valuing the system output. In extensions of this type of approach, various regressions can be used to describe throughput limits, based on a number of global metallurgical parameters.The ultimate position for the optimisation of a mine plan and production schedule is to have a full process plant model running as an integrated part of the mine planning exercise. A plant model suitable for this needs to have all the required sensitivities to input parameters such asfragmentation, grade, mineralogy, strength and hardness. The model then needs to convert these to performance measures for the plant, which include recovery, throughput, product size distributions, energy consumption, water use and operating cost.In this paper an approach is outlined that takes this view and then goes beyond it to provide a full, time-based bottleneck identifi cation and valuation tool.Using such an approach it becomes possible to run mine plans and production schedules in windows of days, weeks, months and over the life-of-mine with a time-enabled process model acting as the active constraint. In this way virtual bottlenecks can be identifi ed for various mine plans and schedules well ahead of time. The value of de-bottlenecking can be defi ned, not just at a plant scale, but in terms of the overall mining operation, and the data can be used as the basis for capital investment decisions.CITATION:Bearman, R A, Cesare, P, Munro, S and Wandel, D, 2014. Incorporation of a full process plant model as an active constraint for mine planning and production scheduling, in Proceedings Orebody Modelling and Strategic Mine Planning Symposium 2014 , pp 121–128 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 24, 2014

By E. A. Adey, C. Baciu, P. Whitbread-Abrutat, M. Varul, T. Ejdemo, R. K. Shail, F. Wall

Responsible mining requires stakeholder engagement throughout all operational stages and after mine closure. By assessing the current and anticipated future socio-economic and environmental impacts, a company can maximise the positive impacts they can have on a community, whilst minimising any negative impacts. Despite the current emphasis on companies maintaining effective stakeholder relations to gain their ‘social license’ to operate, findings of the present study reveal a wide variation in community expectations, with different degrees of ‘acceptability’ evident across seven sites in Romania (Rosia Montana), Sweden (Kristineberg), the United Kingdom (Cornwall), Bosnia Herzegovina (Vihovici) and Russia (Karabash, Gay and Mednogorsk). These variations reflect the current status of mining within a community, as well as its socio-economic background and the nature of existing engagement with mining companies already operating in the region.

Jan 1, 2011

By Matthew Goff, Russell Lutch

The Great Lakes Water Authority (GLWA) operates the largest regional water authority in the State of Michigan. Two of the tunnels supplying raw water to the system from the Detroit River are the Springwells and Northeast Tunnels. The existing 70- to 90-year old concrete lined tunnels have experienced distress and cracking over their life requiring non-structural repairs to sections of the tunnels. For the repair, an interior stainless-steel segmental liner plate system has been designed to restore the watertight capacity of the tunnel liner and resist the exterior hydrostatic groundwater pressure in a dewatered condition. The team is utilizing a “wet repair” approach to perform the necessary repairs while the tunnel remains fully flooded and operational. To test and validate the tunnel repair approach, a full-scale mock-up of the proposed repair has been performed using underwater equipment and divers.

Dec 1, 2022

By Henry A. Wentworth

(New York Meeting, February, 1912.) ELECTROSTATIC separation of ores in its present form is generally known as the Huff' process from the name of Charley H. Huff, of Boston, Mass., through whose constant and persistent labors (with the invention of Clinton E. Dolbear as a basis) the successful commercial process embracing separative machinery and the various electrifying devices has been developed step by step, and the finances for the long period of development provided, and the method finally established and recognized throughout the world as an important and successful addition to the ore-dressing department of metallurgy. The permanent field-success of electrostatic separation began in 1908 with a 20-ton Huff experimental mill built specially for the purpose by the American Zinc, Lead.& Smelting Co., in Platteville, Wis., a plant which was a success from the start and was gradually increased in capacity as the market-conditions warranted to 100 tons of concentrates per day. Much credit is due to the above-mentioned company for its initial venture, and for its assistance in applying the process to field use. Prior to 1908 electrostatic separators had been installed and operated (but for a comparatively short time, however) in a number of places; some under the patents of Mr. Dolbear by himself and associates, and some under the patents of Lucien I. Blake and Lawrence N. Morscher, by W. G. Swart, mining engineer, of Denver, who has always been a courageous advocate of electrostatic separation. Due to the difficulties experienced in the generation of the electrical charges, the primitiveness of the separators, the wooden construction instead of iron as at present, the lack of control of the electrical fields and other difficulties overcome by the later inventions of the Huff Electrostatic Separator Co.,

Jun 1, 1912

By O. A. Ojo, D. L. Chen, N. Zhou, J. Q. Zhang, A. K. Khan

Dual phase (DP) steels are designed to consist of hard martensite dispersed in a relatively soft ferrite matrix, which offers a favorable combination of high strength with good deformability. Fiber laser welding (FLW) is becoming increasingly important for joining advanced materials due to its flexibility and deep penetration. In this study, the microstructure of a dual phase steel, DP980, welded by FLW technique was carefully analysed. Gleeble thermo-mechanical simulation coupled with analytical transmission electron microscopy (TEM) revealed that the FLW process produced significant microstructural changes in a narrow heat affected zone (HAZ) and fusion zone (FZ), which can result in dramatic changes in mechanical properties. This is reflected in the micro-hardness profile obtained across the welded material. The salient phase transitions induced by the FLW, including the formation of new martensite grains in the upper-critical HAZ and FZ, are discussed.

Jan 1, 2014

Iron Ore Resources of the World (Die Eisenersvorrate der Welt)_ By G. Einicke. Verlag Stahleisen, Dusseldorf, 1950. 418 p., with 192 tables and an atlas volume containing 100 p. of reaps. 66 German Marks.-A notable work in which the latest available information on iron ore deposits has been compiled by diligent work, continent by continent, country by country. The author reveals the effect of geological formations, iron content of ore, accessability, cost of transportation, political and economic considerations. Ore beds of importance to the German iron and steel industry are given more space than others. The bibliography contains almost 250 references. A tragic comic feature is the author's complaint that as soon as a map of iron ore resources of a country has been completed, the country's boundaries are changed. Reviewed by W. Trinks, Carnegie Institute of Technology. Industrial Research Laboratories of the United States. National Research Council, Washington, D. C. Ninth Edition. 1950. 445 p. $5.-Contains information on the research laboratories of 2845 industrial and commercial organizations, including names of research executives, location of labs, types of activity, whether any consulting services are offered. There are two appendices, one of which lists data on government labo ratories which cooperate with industry, and the :)ibex naming universities and colleges offering research services to industry.

Jan 2, 1951