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A Special General Meeting of the Institute was held in Kelvin House, Johannesburg on Wednesday, 29th September, 1971. The President, Prof. D. D. Howat opened the meeting at 9.55 a.m. The President read the notice of meeting which was as follows: "In order to bring industry into closer liaison with the work of your Institute and to place the Institute's finances on a sound basis your Council recommends that companies be admitted to membership of the Institute under clause 2.6 of the Constitution, that is, as Non-Corporate members. The designation for this class of member will be that of "Company Affiliate". 2 Membership: This clause to be amended as follows:- 2.6 "Non-Corporate members shall comprise the grades of:- Company Affiliate Honorary Fellow Graduate Associate Student" 2.6.1 This clause to be added:- "Companies involved in or associated with the mining or metallurgical industries are eligible to become company affiliates" 2.14 Add:- "A special certificate shall be issued to all company affiliates". After giving the background to the recommendation made by Council the President asked for a proposer and seconder for the resolution. Mr J. K. E. Douglas proposed and Mr D. G. Maxwell seconded the resolution. The meeting agreed that the constitution be amended as proposed. The meeting closed as 10.05 a.m.

By Hoskings R

Conceptual studies of the run of mine stockpiling and reclaiming requirements at Thiess Bros Pty Ltd South Blackwater coal mine commenced in 1975.Final selection of equipment was made in 1978 and the equipment was commissioncd in June 1979. Equipment selection was made after extensive investigation and visits to existing facilities throughout the world.The equipment selected is described and compared with the alternatives. Foundations were designed to minimise clean up effort and to ensure stabilily of equipment under design wind loading without storm bays. Programmable logic control enables the stacking and reclaiming facility to provide a blended feed to the coal preparation plant.

Jan 1, 1981

By T. R. Curr, W. A. Gericke, J. Basson

South Africa is a leading player in the international ferro alloys industry. Historical factors that have contributed to this dominant position include an abundance of natural resources and relatively low cost electricity. A number of relatively recent developments are potentially threatening this position. These include new legislation affecting the mining and minerals industry, a shortage of some types of suitable reductants, depletion of surplus electricity generation capacity with resultant threat of real escalation of electricity prices and pressure resulting from the recent strengthening of the South African Rand. The industry is addressing these challenges in a number of ways to ensure long-term viability. Some of these measures include investments in more efficient technologies that have economy of scale benefits and are less dependent on expensive reductants and electricity. Local macro-economic impacts include new legislation regarding ownership of enter-prises, mineral rights and royalties on mineral sales, development plans for port and rail infrastructure, as well as initiatives to expand electricity generation and coke production capacity. The fundamentals for being a successful ferro alloy producer are still largely in place for South African producers. Therefore the South African ferro alloy industry will remain competitive and is well placed for continued growth in line with the international growth in ferro alloy demand. The industry should emerge leaner, more efficient and ready to respond to any future demands of the industry. This paper will cover the present status of the industry, the factors that are impacting thereon and a view on its future outlook.

Jan 1, 2007

Critical safety tools to locate miners underground are featured by several exhibitors at MINExpo. Communication was the buzzword for health and safety products at the 2008 MINExpo, and it is still important in 2012. Products unveiled following the Miner Act in 2006 have been upgraded and improved. Saving lives and reducing injuries through better leadership, planning and practice is the goal of every mine professional.

Jan 1, 2012

THE following notes were accumulated during the years 1905 to 1911, when the writer was employed at Stannary Hills. The writer's duty took him over the underground workings daily. In odd moments the geology of the surrounding country was worked out. As the time for this purpose was limited, many interesting points had to be left, untouched. The faulting system in the mines was of such a puzzling character that it seemed as if the geology of the surrounding district might throw some light on it. Dr Jack, in 1907, reported on these mines for the shareholders, but came to no definite conclusions. Unfortunately, the writer has not had access to this report for many years. At the time of his visit the larger develbpments in the Ivanhoe and, Kitchenen orebodies (see Fig 1, B2) were only being opened up. Mr. H. Herman mentions Stannary Hills on p 320, Proceedings Aust Inst ME, new series, No 14, and on p 326 expresses the opinion that the pipe or joint-veins (as at Irvine bank and Stannary Hills) were more valuable to follow than lodes in the granite in that district.GEOLOGY OF DISTRICTThe main feature of the area mapped is a band of altered sedimentary rocks which carry no fossils. It is a mile wide, and consists of a hard band of greywackes 200 ·t ·300 yds. wide, flanked on both sides by contorted shales which become more micaceous as the granite-area to the east is approached. The strata have a general strike of N. 30° W., with a steep westerly dip. A large area of acid intrusive rocks occurs to the west of this band. The outstanding feature of the district is a fault which cuts the sedimentary series in two, to the...

Jan 1, 1918

By Robert N. Roby

This report is one of a series based upon investigations made and being made within the Missouri River Basin in Montana by engineers of the Bureau of Mines , Albany Branch , Mining Division . These investigations are made primarily to provide preliminary information to Department of Interior agencies and others concerned with the planning of the proposed Federal power developments within the Missouri River Basin . The present report has been designed to permit public distribution of the factual data obtained . The field investigations in Meagher County were made during tually all 1948 ; Vir- known metallic mineral occurrences within the county were investigated ; some nonmetallic mineral deposits also were investigated . The investigations cannot be considered complete , however , because some long-inactive mines or prospects may have been missed . Most of the old mine and prospect openings are caved; many are completely inaccessible . Many of the claims located years ago have been abandoned ; others have been relocated under different names and ownerships . Because of such conditions , much of the information regarding their development and operation necessarily has been obtained from Federal and State publications , supplemented by information provided by owners and local residents .

Jan 1, 1950

By JO. E. SHERID

THE Dawson coal-mines are owned and operated by the Stag Canon Fuel Co., of which Dr. James Douglas is President and E. L. Carpenter general manager. The property is situated in Colfax county, N. M., and the openings now in operation are in townships 28 and 29 N. R. 20 E., and township 28 N. R. 21 E., shown in Fig. 1. The mines are part of the southern end of the Raton coal-field, which extends north into Colorado and embraces many coal-camps of the Trinidad section. II. GEOLOGY. Geologically, the coal-measures, commonly known as the Laranmie series of the Cretaceous system, have a thickness of about 800 ft. in the vicinity of Dawson. The coal makes an excellent coke, and, according to some authorities, its coking properties are clue to the action of intruded sheets and sills of igneous rock, the sheets occasionally thickening into masses resembling laccoliths, at such places making nearer approach to the coal and sometimes producing small areas of natural coke. There are but few dikes through¬out the entire southern portion of the field and little or no faulting along the dikes. In some parts of this great coal-field the intrusive sheets are far removed in the green shales below the coal-measures, and are so much altered as to be difficult of identification. There is but little disturbance of the strata through¬out the Raton coal-field in as far as it extends into New Mexico. There are two workable seams in the coal-measures, and two or three smaller coal-seams, ranging from 1 to 2.5 ft. in thick-

Jun 1, 1909

By R. B. Rao, B. Das, J. K. Mohanty, D. S. Rao

Physical, mineralogical and geochemical characterization, along with some beneficiation approach to pre-concentrate the Ni content of the chromite overburden material of the Sukinda Valley, India, have been carried out in detail. Mineralogically, the overburden consists of geothite, quartz, hematite, magnetite and secondary silicates in varying proportions. A specific Ni mineral phase is absent in this material with the Ni and Fe being mostly enriched in finer fractions. Distribution of Ni and Fe in various size fractions and increase of Ni with increase in Fe (goethite content) indicate that goethite is the major Ni-bearing mineral phase. Quantitative estimation of goethite from chemical analysis and weight loss data indicates that the goethite quantity varies from 40% to 90%. Electron microprobe analysis (EPMA) indicates that Nirich and Ni-poor goethite are present in the overburden material. A sequential dissolution study indicates that more than 50% of the Ni are present within the goethite lattice as a lattice substitution. The results of pre-concentration studies (size classification, gravity, flotation and magnetic separation) indicate that Ni is richer in finer fractions. Further, the enrichment of Ni content is limited to 1.1% with 50% recovery by classification followed by hydrocyclone separation of the below 53 m m fraction.

Jan 1, 2000

By B. P. Watson

The Bushveld platinum group metal deposits are two distinct, shallow-dipping stratiform tabular orebodies which strike for many hundreds of kilometres. Mining is extensive, with depths ranging from close-to-surface to 2 300 m. The mining method is a variation of planar open stoping. Pillars are widely employed to support the open stopes. In the deeper levels, in-stope pillars are required to fail in a stable manner soon after being cut, and the residual pillar strength is used to stabilize the hanging wall. These pillars are commonly known as crush pillars. Little work has been done in the past to determine pillar peak and residual strengths, and pillars have been designed using experience and formulae developed for other hard-rock mines. This has led to over and undersize pillars with consequential loss of ore, pillar bursts and potential collapses. This paper describes a crush pillar design methodology, and provides design charts. Three mining environments were incorporated in the investigations, which included underground and laboratory measurements, analytical solutions, numerical model sand back analyses. The results of the study are suitable for the areas where the research was carried out, and may also be applied with caution in other similar environments.

Jan 1, 2010

By D. N. Adams, M. M. Wong, M. J. Robison

Islais Creek Contract E, a transport/storage tunnel in San Francisco, was visited on a fieldtrip during construction by delegates to the 1995 RETC. This paper is a follow-up to that fieldtrip. The project’s two tunnels are 3.7 m and 3.2 m finished diameter, 155 m and 77 m long, respectively. The contractor used 1,000 overlapping jet grout columns to pre-treat the weak Bay Mud along the tunnel alignments, then mined them with an open faced tunnel shield, eliminating the need for compressed air tunneling. This paper documents the jet grouting program and the tunneling operation used on the project.

Jan 1, 1997

By Brian Zelenko, William H. Hansmire

"By the time the latest expansion of the Washington Metropolitan Area Transit Authority (WMATA) system, known locally as Metro and which opened in 1976, is completed in 2020, the system will serve 97 stations and operate on 188 km (117 miles) of track on six interconnecting lines. Metro provides a critical transportation link to a population of approximately six million people within a 3,900-km2 (1,500-sq-mile) Washington Metropolitan area and has allowed job growth to expand to all corners of the region. In the 1950s and 1960s, when the system was first conceived and construction began, most jobs were centered in downtown Washington, and most of the workforce commuted by bus or car. Today, transit-oriented development has increased residential, commercial and government facilities near most of the existing 91 stations increasing the importance of the Metro system as a critical transportation link for the region. According to recent American Public Transportation Association (APTA) data, Metro is the second busiest transit system in the United States (after New York City’s transit system).During the nearly 50 years of construction on the Washington Metro system, technology improvements and lessons learned from the global tunneling industry were implemented. Portions of this background and history have been adapted from other work by the authors Roach et al. (2017) and expanded for use herein. For soil tunnels, these improvements included the change from a “two-pass” tunnel lining with a typical initial lining of steel ribs with wood lagging or segmental precast lining erected within the tunnel shield followed by a final lining of cast-in-place concrete to a one-pass lining system of pre-cast concrete gasketed segmental lining. Soil tunnels were originally excavated using open-face tunnel shields, but changed over time. By the late 1980s, tunneling using closed, pressurizedface tunnel boring machines (TBMs) using a one-pass tunnel lining consisting of segmental precast concrete permitted tunneling in a wider range of soil conditions with much less risk of damaging overlying utilities or structures, greater safety for tunnel construction personnel and without the need to dewater the soils. However, due to concerns about conditioning clays with earth pressure balance (EPB) TBMs, open face machines were still favored by contractors for their better advance rates, lower cost and ability to deal with boulders that were occasionally encountered in the Coastal Plain Terrace Deposits."

Jan 6, 2018

By R. C. Troxell, S. C. Sun

EFFORTS to obtain definite quantitative data when employing the currently used bubble pick-up method1,2 as a pre-flotation investigation tool led to the adoption of the magnifying mirror method and the microscopic method modifications. Quantitative data obtained by these two methods were converted into bubble pick-up indices and bubble pick-up coefficients. Rough correlations were established between the calculated indices and the results of contact angle testing as well as actual flotation under the same conditions. The basic steps of the magnifying mirror method are as follows: 1—mixing 200 ml distilled water, sized and cleaned mineral particles of approximately 0.5 g, pH regulator, and flotation reagents in a glass beaker; 2—swirling the mineral particles to the center of the beaker to leave a clear circumference; 3—pressing an air bubble against the mineral particles for about 1 sec, and then moving the mineralized air bubble to the clear part of the beaker; and 4—dropping all the attached mineral particles of the air bubble by tapping the bubble holder, and counting the number of the dropped particles by looking at the magnified image in the mirror positioned beneath the beaker. This method is impractical for mineral particles which are transparent in water or finer than 200 mesh. The microscopic method is essentially similar to the above described magnifying mirror method, with the exception that the mineralized air bubble was drawn up into the bubble holder and subsequently discharged onto an externally placed watch glass, where the number of pick-up particles was counted with the aid of a microscope or hand lens. Drying was necessary when the discharged liquid interfered with the counting. The results of the bubble pick-up tests can be simply expressed in the form of the actual count. However, this can be misleading because the number of pick-up particles varies not only with the size of bubble but also with the size of particles. This short-coming is largely remedied by the use of the bubble pick-up index. as calculated from the following equation: PI = (pn/p) 100 [1] in which PI and pn are respectively the pick-up index and the number of pick-up particles under any test conditions, and p is the maximum number of pick-up particles of the same mineral under optimum flotation conditions, with the same size holder and particle. The bubble pick-up coefficient is a term coined to denote the difference between the bubble pick-up index of mineral particles in a liquid and that of the same mineral-liquid mixture plus a chemical reagent at the same pH value. For example, the difference between the pick-up index of a naturally floatable bituminous coal in a solution of water and kerosene and that of the same coal in water alone is a bubble pick-up coefficient. Compared with the contact angle method, the quantitative bubble pick-up method is inferior in accuracy but superior in sensitivity. Other advantages of the bubble pick-up method are that the apparatus can be easily assembled, the mineral sample is conventionally prepared, and the test procedure is relatively simple. References S. R. B. Cooke: The Flotation of Quartz Using Calcium Ion As Activator, Trans. AIME (1949) 184, p. 306. 'G. A. Last and M. A. Cook: Theory of Collector-Depressant Equilibrium at Mineral Surfaces. Paper presented at St. Louis Meeting, AIME (February, 1951).

Jan 1, 1954

By N. C. Saxena, S. K. Puri, A. K. Pal

The condition-based monitoring system is an important innovation for reducing the downtime of costly, heavy earth- moving machinery (HEMM). Vibration severity measurements were made on the HEMM located at the Gevra Project, the largest coal opencast project in India. Whenever the vibration severity levels exceeded the permissible limits, necessary actions were taken to replace the defective parts of the ma- chine. The systematic vibration monitoring of 120-t (132-st) dumpers, followed by corrective measures led to a substantial increase in component life (8.18% for an 445E Dressor and 28.44% for an MK-30 Unit Rig). The associated costs (including spareparts) were reduced by 21.55% and 25.74%, respectively. Because of the reduced downtime, savings for these two dumpers over the period from March 26 to June 25,1998, were of the order of Rs.26.47 (US$0.649) million.

Jan 1, 2000

By Jonas Olsson

"The picture of China as an antiquated continent is changing rapidly and fast-forwarding progress is a fact in most infrastructural fields. Mining is not an exception. China is today the largest producer of aluminum, coal, steel, zinc, tin, lead and manganese and the country’s mineral resources comprising approximately 12% of the global reserves ranks them number three in the world after US and Russia.In order to feed the growth industry is needed to take extra ordinary strides to improve supply of raw material and Chinese mines are continuously being upgraded with the latest western technology to meet the increasing domestic demand of base metals.In Anshan located in China’s northeast province Liaoning we find one of the fastest developing mining companies, Angang Iron & Steel Group Co. Ltd. With their six mines that together process approximately 60 M ton iron ore/year Angang Iron & Steel Group Co. Ltd is the largest iron ore company in China. The group’s thorough pre-studies and technical evaluations over the past five years have made them very successful in both plant upgrades of existing operations and green field projects.INTRODUCTIONWe live in a time when the world market is gradually acclimatising to the global consequences of “The China effect”. An effect caused by a formerly sleeping giant nation that during the last years has awakened and developed beyond comparison, primarily because of booming infrastructure projects and demand for capital and consumer goods"

Jan 1, 2006

By Staff

One hundred thousand miles of flying over the North country without a single air casualty; much of it over virgin territory probably never before visited by white men; some of it over regions that abound with possibilities for minerals; all of it effective, for exploration and the establishment of bases and supply-stations, and for the carrying of men and their tools and provisions- this, briefly, is the record of Northern Aerial Minerals Exploration, Limited, a Canadian company organized Jess than nine months ago, which has been functioning, without interruption, during spring, summer, and now into winter. Our planes have ranged from the Alaskan boundary on the west to the Labrador coast on the east, and from the Transcontinental railway north to the Arctic circle. Our prospectors, carried on trips of hundreds, and occasionally thousands, of miles, have gone over large sections of country which were never before explored, and at the end of the prospecting season the Company finds itself in possession of several groups of important gold claims, which look most promising. In addition to this, we have been in contact with deposits of almost every known mineral.

Jan 1, 1929

By J. H. East, D. Harrington

"INTRODUCTION Mining at its best is not a clean occupation for either surface or underground employees; and this applies alike to coal, metal, and non-metallic mines. The employees are handling minerals that have been blasted, or broken by some means and are subjected to mineral dust, whether it is coal, quartz, or talc. The employees usually wear clothes specifically adapted to the work in which they are engaged, and frequently these clothes are not suitable for use away from the mine. Many mines are wet, and employees must wear rubber boots to remain at least partly dry, and even on relatively dry mines, some parts of the mines usually have water falling from overhead, there are accumulations of water, or the floor or other surfaces are wet or muddy, Some mines are dusty, and the air-borne dust quickly settles on the clothes and body of the miner, especially, when he is working in confined areas, or in places that are hot, humid, or poorly ventilated. Most occupations around a coal tipple, anthracite breaker, or a mill at a metal or nonmetallic mine have their own problems of cleanliness as to skin or clothes or both. Mining in any of its phases is inherently dirty work, and the employees dress accordingly while at work.In the early stages of mining it was the custom or workers to wear their dirty clothes home and change there. This necessitated their going home after work in dirty clothes which were usually damp from perspiration or from contact with wet or muddy matelials or surfaces, and, in addition to being inconvenient this was a frequent cause of colds, pneumonia, other pulmonary diseases or, possible skin ailments. Men working in very wet mines found that it was more satisfactory to change into dry clothes in the boiler room at the mine after work and allow their wet clothes to dry overnight. The mining companies later provided the first of the so-called ""dry-houses"" which were heated but had, few, if any, conveniences, such as showers, lockers, or latrines. The miners changed into dry clothes after work, but would not bathe or ""clean up"" until they reached their homes. Later, progressive mining companies provided bathing facilities for the employees, and eventually the present modern wash and change houses were evolved. Unfortunately, many mines, still have no bathing accommodations, and many have only makeshift accommodations."

Dec 1, 1947

One of the most common critical areas of longwall mining in terms of ground stability are the gateroad and bleeder entries. These critical entries provide much-needed safe access for miners and allow for adequate ventilation required for dilution of hazardous airborne contaminants and must remain open during mining of a multi-panel district. This paper focuses on the stability of the longwall entries subjected to a single abutment load such as bleeders, first tailgate, and last headgate. First tailgate and last headgate are also referred to as blind headgates and tailgates. A study of a longwall district through conditions mapping, support evaluations, and numerical modeling was conducted and evaluated by researchers from the National Institute for Occupational Safety and Health (NIOSH). The condition mapping and support evaluations were performed on entries that spanned the previous five years of mining and relied on a diverse selection of supports to maintain the functionality of the entry. Numerical modeling was also conducted to evaluate various support types with further investigation and comparison to the condition mapping. The study demonstrated the importance of the abutment load decay versus distance from the gob edge, the potential for a reduction in material handling related injuries, as well as optimal usage of secondary and standing support.

Jan 7, 2020

By L. O. Howard

THERE are three active mines in the Chewelah-Colville district, the United Silver Copper near Chewelah, and the Old Dominion and the Chloride Queen near Colville. The Admiral near Valley is also doing development work. The Chewelah district is in the south central part of Stevens County in the Colville Valley. Chewelah, a thriving town of 1600 people, and the scene of operations of the Northwest Magnesite Co., is about the center of the district. It is situated in a farming community on the Spokane-Nelson branch of the Great Northern railway, about 65 miles north of Spokane. Only two or three of the mines in the district have been extensively developed, although many have been prospected. The general elevation of the valley, is about 1600 or 1700 ft., that of the mountain ranges on each side about 3000 to 4000 ft., with gentle slopes and rounded glaciated tops. Prospecting is often difficult because of much glacial debris.

Jan 1, 1925

By R. E. Wilmot

This paper is based on the experiences, over many years, on the part of numerous authors in the South African mining industry and that of the hot dip galvanizing process and its application as a corrosion protection system. The paper sets out the extensive development, financial resources and stringent operating requirements of the South African mining industry. After many years of research and operational experiences, hot dip galvanizing and when necessary, duplex systems, have been found to meet the demanding requirements of this particular industry. The paper sets out the requirements from the standpoint of corrosion criteria and is followed with a practical example; ?case history? where the corrosion protection properties of hot dip galvanizing are demonstrated. This case history traces the early investigation of the expected corrosive conditions to be encountered in a new mining operation (now 10 years on) and concludes with two follow up visits to the mine in order to examine actual performance of the corrosion protection system after ten years in service.

Jan 1, 2006

By J. L. Wiley

THIS REVIEW contains abstracts of the technical literature and patents dealing with the history, development, and commercial application of the Bergius and related processes for the hydrogenation, under greater than atmospheric pressures, of liquid and solid carbonaceous materials such as coal, lignite, their distillation and extraction products, pitches and tars, and petroleum and its distillation residues. An attempt has been made to include abstracts of all the published information on this process and of as much of the captured foreign documents and reports compiled therefrom as could consistently be reviewed during the time allotted for the work. Contact with the current literature and patents and review of the foreign documents will be continued and the information will appear in Synthetic Liquid Fuels Abstracts, which is being issued bimonthly as a Bureau of Mines publication. The material in this review is divided in two sections-literature (part I) and patents (part II)-and each of these is arranged alphabetically by author or patentee with further chronological arrangement under each author or group of authors. Secondary authors and patentees as well as assignees are cross-indexed to the main entry. In serial articles or reports the complete series appears in the alphabetical arrangement according to the author of the first member of the series. Succeeding members as well as secondary authors are entered as cross references; Titles of the journals are used as the authors in anonymous references. By following such a procedure, an author index is not required. However, a detailed subject index and a numerical patent list by countries are given as part III.

Jan 1, 1950