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By W. A. Gibson, A. D. Trujillo

The Santa Rita copper deposit first served as a source of native copper for Indian implements and weapons. In 1801 Santa Rita copper, trans- ported by mule train to Chihuahua, began to be used commercially for making coins. It was a small- scale operation made difficult by Indian raids, transportation costs and depletion of the higher grade ores. There was, moreover, no known method for economically extracting copper from the under- lying low grade sulfide ores. Originally, copper and copper oxide ores were mined by underground methods, but there was virtually no development of the deposit-which became United States territory after the Treaty of Guadalupe Hidalgo in 1848-for almost a hundred years. A number of small underground mines had been started during that time, but it was not until 1873 that all the principal claims were consolidated under one control.

Jan 1, 1966

By A. L. Podia

The purpose of this research was to develop a system capable of detecting changes in the structure of rocks, leading to failure of mine roofs, and/or excavations. A prototype system was developed, field tested and delivered to the United States Bureau of Mines for further evaluation and research. This system is based on the analysis of acoustic signals generated on the surface of the roof by an impact device and which are reflected or backscattered by flaws and discontinuities in the rock. The specially designed impact source is capable of generating high frequency acoustic signals with excellent repeatability. The system can also be used in conjunction with conventional acoustic pulse transducers. The received signal is digitized and the data transferred to a minicomputer for processing and display. This capability allows the immediate determination of wave velocity and/or distance to a reflecting interface. Various data processing techniques such as averaging, differentiating, and comparing of different signals can be selected by entering the appropriate commands on the keyboard. Being a programmable system it is possible to implement more advanced signal processing techniques. All results as well as the signal are displayed on a CRT. Furthermore, a permanent record of the data can be generated on paper tape, which can be reentered and processed at a later date. A communications interface allows transmission of the sampled signal to a large scale re-mote computer. The system was tested extensively in the laboratory, and field tested at the York Canyon Coal Mine. These tests proved the feasibility of operation in the mining environment. Results indicate that further investigation and development will have to be undertaken to fully develop the potential of this system in satisfying the goals of this research.

Jan 1, 1973

By H. A. Doerner

"The following report is submitted, in compliance with the request made by the Honorable W. H. Sproule, Chairman of the Committee on Mines and Mining, to the Director of the United States Bureau of Mines, that the bureau investigate the most modern processes for the production of radium from its ores. A thorough search of technical publications and patent office files was made. Outstanding authorities on the subject as well as persons claiming novel or secret methods were interviewed.Unlike most other elements, it is not possible for radium to occur naturally in a pure or concentrated form. This is because radium is one of a series of unstable elements which, by a constant, spontaneous, atomic disintegration, change from one element to the next in the series. Uranium is the ""grandparent"" of radium. The rates at which radium atoms are ""born"" and ""die"" are so related that only one part of radium can exist in equilibrium with three million parts of uranium. Consequently radium is only found associated with uranium minerals, and the ratio of radium to uranium is never more than one to three million. Since uranium is a rather rare element, the scarcity of radium is almost beyond comprehension. Nevertheless minute traces of radium can be detected in nearly all rocks.The carnotite ores of Colorado and Utah were the chief source of radium for many years.In the fall of 1922 news of the very rich deposits of radium ore discovered in the Belgian Congo caused most complete cessation of domestic production. The Congo ore contains pitchblende and a number of alteration products, including the new minerals bequerelite, curite, krasolite, stasite, and dewindite. Reports indicate that a considerable amount of ore containing over 50 per cent uranium oxide has been produced. It seemed certain that radium could be extracted from the Conga ore at a much lower cost than from the relatively low-grade carnotite; and in order to preserve their elaborate marketing organizations, the larger American producers made agreements with the Belgian syndicate to market the foreign product in this country. The retail price of radium has been held at $70 per milligram, but large orders are filled as low as $50. Extraction of radium from carnotite by the usual methods does not appear to be profitable at that price with one exception, all American firms ceased production after their accumulated stocks of ore had been treated. The United States Radium Co., which continued to treat carnotite for several years, finally shut down its plant."

Dec 1, 1930

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

By V. H. Gottschalk

Sponge iron is a product resulting from the reduction of an iron oxide below the temperature at which the product melts. Commercial grades usually contain 80 to 95 percent metallic iron, 2 to 5 percent unreduced iron oxide, and an amount of siliceous gangue material depending on the pur.ity of the are used for reduction. The reducing agent may be gaseous or solid, and a large variety of procedures have been proposed for bringing the reducing agent into reaction with the iron oxide. Of the proposed procedures, the one that has the distinction of having been in continuous commercial operation for the longest time, from 1911 to date, was developed at a ceramic plant in Hoeganaes, Sweden, and yields? a product that has an enviable reputation as furnace feed wherever special, high-quality steels are made.

Jan 1, 1948

By Jennifer A. Slatnick

Chlorofluorocarbons (CFC's), once universally accepted as ideal compounds for use in cooling and refrigeration, in foam production, and in cleaning electronic components, are being phased out and eventually banned under extensive international agreements because the chlorine in CFC's is thought to deplete the Earth's ozone layer. The industry has responded with the introduction of alternatives in the form of hydrofluorocarbons (HFC's), which contain no chlorine, and with hydrochlorofluorocarbons (HCFC's), which fill an intermediate gap in the replacement of CFC's. As a result of the elimination of chlorine in the HFC's and the reduction of it in the HCFC's, these alternatives contain more fluorine than the CFC's do. Other nonfluorocarbon substitutes, known as not-in-kind alternatives, contain no fluorine at all. As a result, the fluorspar mining industry, which is the source of fluorine in fluorocarbons through intermediate hydrofluoric acid, is being affected. Concern for this impact has led the U.S. Bureau of Mines to employ its capabilities to analyze various scenarios in the evolution of CFC replacements and substitutes to determine their effect on fluorspar mining. This report utilizes a network flow model to examine the effects of proposed replacements for CFC's, in terms of fluorine content, on fluorspar operations worldwide and on hydrofluoric acid plants in North America and Europe.

Jan 1, 1994

By HILAND BATCHELLER

COMMENT on the economic significance of the special alloy steels seems inevitably to reduce itself to an attempt to peer into the future of the industry in which we are interested. We are all familiar with the historical development of iron and with the almost complete replacement of iron by steel. Those who have been connected with the industry since its .early days have had the satisfaction of witnessing the greatest industrial development the world has seen. As the cartoonists of the muck-raking decade liked to picture steel as an ogre armed with a spiked club, his hands reeking with blood and with golden coins dripping from his pocket, fiercely seeking for more widows and orphans to devour, I choose to call on my imagination to create a gigantic but beneficent robot of such marvellous mechanical skill. that it quickly transforms millions of tons of otherwise worthless material into the infinite variety of useful products which are so largely responsible for our present civilization.

Jan 1, 1931

By Donald Bruce

The three types of specifications which are used for micropile work are: ? Performance Specifications: The contractor is permitted control over certain design and/or construction procedures but must demonstrate to the owner through testing and/or certification that the final product meets the specified performance criteria. This method allows and encourages the contractor to provide a competitive and/or innovative micropile design within the framework of the overall design requirements. The responsibilities for the work are shared between the owner and the contractor. ? Open Specifications: These leave the scope and design of the installation up to the micropile contractor. This method is the most common for securing bids on temporary micropile work. The responsibility for design and performance is clearly placed on the contractor. Open specifications are not recommended for permanent applications. This method allows the contractor to select the most economical micropile system. ? Prescriptive Specification: The Owner describes specific procedures that must be followed, but which may not necessarily describe the objective of the work. When prescriptive specifications are used, the owner is responsible for the proper performance of the system. The contractor is responsible for satisfying the details of the specifications. Performance specifications are the most common and best reflect the challenges and interests of micropile technology and applications.

Jan 1, 2004

This Kaiser Engineers report on the feasibility of surface mining on the North Slope of Alaska has considered the quantity and quality of the North Slope deposits with attention paid to the economic, technical, and environmental constraints of the mining systems suggested for the three candidate minesites at Kukpowruk River, Elusive Creek, and Kuk River. Site selection, based on coal rank and quality as well as seam thickness and geometry, also considered demonstrated and hypothetical reserves relative to three mining systems (dragline, shovel, dragline and shovel), mining equipment requirements, infrastructure, and transportation relative to the Arctic environment and costed for potential markets. Throughout the report the delicate permafrost environment has received particular consideration. Recommendations based on the technical, economic, and environmental feasibility of mining the coal deposits of Northern Alaska by surface mining techniques have resulted in two conclusions: 1. The coal deposits can be mined with currently available technology; 2. It is uneconomic to mine these coals given current coal resource estimates, costs, and market conditions. A literature survey is included in appendix.

Jan 1, 1977

By Joint Micropiles Committee

"The three types of specifications which are used for micropile work are: • Performance Specifications: The contractor is permitted control over certain design and/or construction procedures but must demonstrate to the owner through testing and/or certification that the final product meets the specified performance criteria. This method allows and encourages the contractor to provide a competitive and/or innovative micropile design within the framework of the overall design requirements. The responsibilities for the work are shared between the owner and the contractor. • Open Specifications: These leave the scope and design of the installation up to the micropile contractor. This method is the most common for securing bids on temporary micropile work. The responsibility for design and performance is clearly placed on the contractor. Open specifications are not recommended for permanent applications. This method allows the contractor to select the most economical micropile system. • Prescriptive Specification: The Owner describes specific procedures that must be followed, but which may not necessarily describe the objective of the work. When prescriptive specifications are used, the owner is responsible for the proper performance of the system. The contractor is responsible for satisfying the details of the specifications.Performance specifications are the most common and best reflect the challenges and interests of micropile technology and applications.The owner, designer and contractor will together be responsible for the tasks associated with the design, installation, acceptance, and performance of the micropiles. The installation of micropiles requires specialized equipment, techniques, and appropriate workmanship. Not every detail of the work can be specified, and not every potential problem can be anticipated. Therefore, a contractor who has demonstrated experience in micropiles must be selected to execute the work required."

Jan 1, 2004

By The Honourable George Prudham

"I AM PLEASED indeed to be present with you here today and to be taking part in the proceedings of your convention. You have been greeted and welcomed to the Province by Premier Manning who is also provincial Minister of Mines and Minerals, and to this City by Mayor Hawrelak. As Minister of Mines and Technical Surveys in the federal government and as Member of Parliament for Edmonton West, I have been asked to share the honour of extending greetings and a cordial welcome to all.It is a happy coincidence that this representative national gathering, indicative of the growing strength and significance of a great basic Canadian industry, is taking place in the Macdonald Hotel, the new addition of which marks another important step forward in the progress of this City and district.This happens to be the third national convention of the C.I.M. that I •have had the pleasure of attending and I trust that I am not presumptuous in expressing the hope that I will have the opportunity of attending many more conventions of the Institute in my present capacity.Dr. Kidd has bestowed on me a high honour by asking me to be Co-Chairman of this Inaugural Session of the Convention and thus to share with him the responsibility of presiding over the proceedings of this afternoon."

Jan 1, 1953

By G. M. Bond

Reduction of the emissions of greenhouse gases, such as CO,, is currently the subject of extensive research. A novel strategy is put forward here, based on a biomimetic approach providing accelerated deposition into carbonate form for long-term sequestration. It offers the advantages of a process that: does not require concentration of CO, from flue gases; could potentially be used in an on-site scrubber to provide a plant-by-plant solution to reducing CO, emissions; is an environmentally benign procss with an environmentally benign product; and is based on readily available, low-cost reagents (except perhaps the catalyst).

Jan 1, 1999

By K Ringwood, J Cummings, C J. Moran

The development of a water accounting framework that enables consistent and contextual reporting of minerals operationsÆ water use, represents a key sustainable development objective that many Australian minerals companies have committed to. A future water accounting framework will require: key terms and definitions for water metrics for use in the Australian minerals industry that are consistent with the wider water sector, a suite of metrics representing key components of an operationÆs water balance, a calculation method for some of the metrics, and a reporting protocol. This paper presents the methodology that was used to derive these four components. Existing accounting frameworks were reviewed and key terms and definitions that were consistent with current regulatory requirements and voluntary approaches were proposed. A calculation methodology was developed to obtain some of the key indicators and variables that cannot be easily measured directly (eg water loss through evaporation). The adopted terms and definitions typically require a combination of empirical and estimated data. To test the proposed definitions and calculation methodology, values for water metrics were derived for eight sites, selected to test a variety of commodity and biophysical situations. The proposed framework and definitions could deal with the specific situations selected as case studies. The associated calculation methodology produced complete accounts at various levels. Some elements of the accounts could be directly checked against available data and simulations. The framework captured well variations in the reuse efficiencies; reuse efficiency could even vary for similar processes. It is concluded that this preliminary accounting framework provides a consistent language and metrics for quantifying and communicating water management, both at the intersection of the site with the surrounding landscape (through detailed reporting of site inputs and outputs) and within operational activities. Using this consistent framework for quantifying and documenting water use within an operation will provide a platform for compiling and comparing minerals industry water use with other sectors. This may support benchmarking activities within regions or companies and help demonstrate leadership amongst water users in water resource stewardship. The approach presented here is applicable to a wide variety of mining and processing activities, and biophysical environments, and following a period of stakeholder engagement and third party review, is being refined as a first step towards developing nationally consistent water use reporting for the Australian minerals industry.

Jan 1, 2009

By William O. Vanderburg

This paper 3/gives the results of a reconnaissance of mining districts in Clark County, Nev., made from November 18 to December 22, 1936, and from February 9 to March 8, 1937-in all, 63 days. While the field work Was being done, virtually all of the mining districts in the county were visited and many data on active and inactive properties were obtained. The report covers the locations of the various mining districts, the nature of the deposits, information on past operations, current activity, and general data likely to be useful to operators, investors, and others interested in mining. The geology of the deposits is discussed only briefly. The principal metal-mining districts in the county are Goodsprings, Eldorado, and Searchlight. The zinc-lead ores of Goodsprings have been the most important economically, followed by the gold-silver ores of Eldorado and Searchlight. In the industrial-mineral field, gypsum, limestone, silica sand, and borates are the principal products. Metal mining in the county is characterized by numerous small operations and the ores are either milled locally or shipped to distant smelters.

Jan 1, 1937

By J. H. East

THE RIFLE, COLO., oil-shale project of the Bureau of Mines was a facet of the re-search and development activities conducted under the Synthetic Liquid Fuels Act (Public Law 78-290) of April 5, 1944. The principal objectives were to devise efficient methods to mine and retort oil shale and to refine shale oil into usable products, at a total cost low enough that shale oil could supplement the domestic supply of petroleum at competitive prices. The Rifle project included three major divisions: (1) Mining, (2) retorting, and (3) refining. The major functions of the mining program were to supply oil shale to the retorts, to devise mining procedures, and to develop an under-ground-mining method by which oil shale could be produced safely at an unusually low cost per ton. The selected mining procedures and direct mining costs were demonstrated by sustained test runs.

Jan 1, 1964

By Andrew McGrath, Geraldine Lyons, Sarah Barcelona

In the dynamic and challenging modern industry landscape, understanding and unleashing the true role and contribution of technical teams is crucial to business success. The cyclical nature of industries has led to shifts in the technical professional’s place within the organization and the technical skills that are desired most. This paper reframes the pivotal role that technical professionals play within complex operating assets to maximize value and realize full potential. This investigation focuses on the Rio Tinto Kennecott Technical group’s cultural journey, which is underpinned by an investment in its people. The conflict between legacy industry beliefs and the necessity for cultural change emerges. This is illustrated by a deep dive into the evolving case study of Kennecott’s Bingham Canyon Open Pit Mine Technical team. Here, a multi-faceted approach to cultural change is helping to unlock the team’s contribution to the life extension of an aging asset. Guided by a vision and strategic roadmap, this approach is part way through a 5-year implementation period and is yielding encouraging business outcomes.

Feb 1, 2024

By Benjamin Smith Lyman

PAGE I. ANCIENT HISTORY,........... 57 Accepted Fables ; Babylonian Mapping ; First Surveying. II. COMPASS,.............59 Chinese Invention; Marco Polo; First European Compasses ; Early Knowledge of Variation ; Plotting with the Compass ; Hanging-Com pass ; Supposed Gravitational Error ; Merit of the Compass. 111. Telescope,............63 Origin (Roger Bacon, Porta, Digges, Lippershey, Galileo) ; Improvements (Micrometer and Cross-Hairs, Rittenhouse's First Telescope, Platinum Cross-Wires, Telescopic Sights, Reflecting Telescope, Achromatic Lens, Kellner Lens in Erecting Telescope, Inverting Telescope). IV. Theodolite,.............81 Origin ; Derivation of the Name. V. TranBit,.............86 First Surveying Transit; Edmund Draper. VI. Instrument-Parts,..........89 Ramsdenl a Dividing Engine ; Fineness of Graduation ; Conical Gradua tions ; Full Vertical Circle ; Leveling-Screws ; Shifting Tripod-Heads ; Hoffman-Harden Tripod-Head ; Heller & Brightly's Improvements. VII. OTHER INSTRUMENTS AND APPLIANCES,......100 Sunflower; Plummet-Lamp; Chains and Tapes. VIII. SCOTT'S TACHYMETER,.........104 IX. Nomenclature and Classification,.......105 Names; Grouping. Surveyors are much indebted to Mr. Scott for so vigorously attacking the subject of the origin and history of mine-surveging instruments, the compass, the telescope, the transit and other apparatus. He is not afraid of the dark, nor yet foolishly bashful in broad daylight. He does not recoil from the obscurities of the earliest times and the most difficult historical points; and, with commendable public spirit, he makes his own invention known to his fellow-workers, and challenges their criticism. He has, moreover, elicited the praiseworthy emula-

Jan 1, 1902

By R. W. Smith

Living and killed organisms, particularly microorganisms, and extracellular products derived from the organisms are increasingly finding use in minerals engineering. Goals include both enhancement of mineral processing/11.ydrometallurgica,l operations and remediation of mineral industry wastes. Some of the applications, such as biologically assisted leaching of ?sulfide ores and bioxidation of refractory gold ores, are well established commercial ?processes used around the world. Others, such as the use. of organisms for the removal of heavy metal ions from dilute aqueous streams, are nearing commercial application. Many other uses of microorganisms and. their derivatives are potentially possible. These include use of microorganisms in flocculation or flotation of minerals., remediation of organics potentially discharged from mineral engineering operations, degradation of cyanide, the recovery of bitumen from heavy oil reservoirs and tar sands and the solubilisation of lignites and low rank coals. In order to fully exploit these many possible uses of organisms and their derivatives, extensive fundamental .and .applied research work exploring the fundamentals, potential and practicality of the various possible uses of microorganisms in mineral engineering should be vigorously pursued. ?

Jan 1, 1991

By H. F. Moore

DURING the last six years, there have been many extensive investigations of the fatigue of metals. The major work of 'these investigations has been the determination of constants for fatigue strength of wrought ferrous metals; but during the past year or two there have become available considerable test data on the fatigue strength of certain nonrferrous metals, including copper, brass, bronze, nickel, copper-nickel alloys, aluminum and aluminum alloys, magnesium and magnesium alloys. It is not proposed to give here extensive quantitative tables of test results; for such tables, reference is made to the published data of various laboratories. The following general conclusions, however, seem to be fairly well established: 1. The phenomenon known as "fatigue" of metal really a progressive fracture of metals. A minute (probably submicroscopic) crack is formed in the metal, the internat stress, is intensified at the ends' of the crack, and under successive applications of load the crack spreads like a minute hacksaw cut until there is not enough sound metal left in the cross-section of the piece to stand the load. applied, and then failure occurs suddenly. 2. For wrought ferrous metals, there is .a limiting intensity of stress (as computed by the ordinary formulas of mechanics of materials) below which, a metal is able to withstand an indefinitely large number of repetitions of stress without failure. This limiting stress is known as the "endurance limit or the fatigue limit.? For reversed flexure, the endurance limit for. wrought ferrous metals is usually not far from 50 per cent. of the ultimate tensile strength.

Jan 1, 1925

By ABBOT A. HANKS

WHEN gold was discovered in California, and San Francisco grew almost over night from a handful of people to many thousands, one of the first difficulties experienced was the lack of money. Gold dust in considerable quantities was rushed into the city from the various mining camps but there was no money. Purchases were paid for by weighing out dust in hand scales. We can appreciate' the difficulty of paying for a drink or buying a postage stamp under these conditions. All this gold was in the form of dust from placer workings and the first metallurgists were the assayers' who melted and refined this gold, casting it into bars which were weighed, assayed, stamped with fineness; value, and the name of the assayer. Many .of these plants were of considerable size, handling shipments that were accumulated by banks and express companies throughout the "Diggings" and sent to San Francisco to be shipped by water to the eastern states. Several

Jan 1, 1931