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By William M. Luff

This paper outlines the regional geology and history of the area, and summarizes the stratigraphy, structure and geology of the Brunswick No. 12 mine area. The Brunswick No. 12 deposit is a stratiform massive sulphide body. It occurs in rocks of the Tetagouche Group, which is believed to range in age from Lower to Middle Ordovician. The stratigraphic sequence, including the stratiform orebody, in ascending order consists of older metasedimentary rocks, augen schist, metasediments, augen. schist, footwall metasediments, the -massive sulphide body, iron formation, hanging-wall metasediments, siliceous tuff, basic volcanic rocks , basic iron formation and a porphyry dyke. This sequence is similar to that at some other deposits in the area. Four phases of structural deformation are known to be present in the Brunswick No. 12 mine area. The first deformation folds (F1 ) and associated faulting are the most important factors in determining the distribution of the massive sulphides. This deformation has resulted in the massive sulphides being separated into four zones: the Main Zone, the West Zone, the East Zone and the V-2 Zone. Brunswick Mining and Smelting Corporation Limited is actively mining, developing and exploring the deposit.

Jan 1, 1977

By K. A. Perry, R. Q. Eades

The University of Kentucky conducted inerting tests and angle of ejection tests on three types of rock dust. A newly developed hydrophobic dust was compared against typical dry and wet dust applications. This new product is designed to alleviate respirable dust concerns for dry dusting and caking issues with wet dusting. Samples for both test types were prepared in a laboratory and subjected to temperature and humidity cycles that are typical of an underground coal mine. Inerting tests were conducted in a 38-L chamber with a 5-kJ Sobbe igniter. Angle of ejection testing was conducted at the University of Kentucky Explosives Research Team’s laboratory in Georgetown, KY. The results of these tests indicate that the newly developed dust has improved results for flame suppression and ejection compared with typical wet dust applications. The significance of these results is discussed with regard to existing respirable dust regulations and the issues associated with caking.

Jan 1, 2016

By I. M. Ritchie

Cyanide owes its great success as a lixivant for gold to the great strength of the Au-CN bond. A replacement for cyanide must similarly be a strong complexant for gold (I) or gold (III). The various alternatives are briefly considered and it is concluded that only thiosulfate has a reasonable chance of replacing cyanide as a relatively non-toxic lixivant at the present time. However, there are considerable technical problems to be overcome before thiosulfate can be considered to be a realistic alternative to cyanide. Firstly, the leaching of gold using aerated ammoniacal thiosulfate with copper as a catalyst is a complex process which needs to be understood and controlled carefully in order to achieve maximum recoveries with minimum reagent losses. Secondly, there needs to be an option similar to the CIP process for recovering and concentrating the dissolved gold thiosulfate complex from pulps produced in the processing of low grade gold ores. The prospects for overcoming these technical' challenges are evaluated and discussed.

Jan 1, 1998

By Constantino Capurro

For certain applications, coarse titanium nitride (TiN) precipitates can be deleterious for the final properties of the material. Hence, in order to better understand the mechanisms involved in the generation of these precipitates, a thorough characterization of the particles observed in steels with different titanium and nitrogen content was carried out. Samples from liquid steel (tundish), continuous casting billets and final product were evaluated using an Automatic Particle Analyzer (APA) coupled to a Scanning Electronic Microscope (SEM). The location, frequency, size distribution and composition of the different particles observed were assessed. While only few TiN precipitates were observed in liquid steel samples, the density of this type of particle significantly increased in the continuous casting billets samples. Particles ranging from 1 to 10 µm were mainly found in the interdendritic zones of the as-cast structure. The density of TiN particles observed in these samples did not change after re-heating and rolling operations. A model to predict TiN precipitation during solidification was developed. A reasonable agreement was found between model results and measured data. Results of this analysis confirmed that the precipitated fraction of TiN increases as the product of steel Ti and N contents rises.

Oct 30, 2017

By I. Martinez-Dominguez

In September 1992, mining in Mexico was opened again to foreign investment by President Salinas-de Gortari, after thirty years of "Mexicanization" of mining industry which limited foreign participation up to a 49 % (or 34 % in case of national reserves) on a Mexican mining corporation. During said period mining in Mexico was controlled by four or five big mining companies and besides mining production was focused mainly on silver, lead, zinc, copper and fluorspar. Suddenly in middle of a big crisis on Mexican mining industry due to low prices of minerals in the world and also in a period on which it seems that mining industry in the United States and Canada has been condemned to die for environmental reasons, it appears a new Mexican Mining Law to permit foreigners to participate in mining in Mexico' trough Mexican mining corporations that they may control up to 100 %

Jan 1, 1994

By H. D. Yu

In this paper, an evaluation about the process mineralogy of the rich iron mine in Mongolia with comprehensive methods is given; this provides foundation of the comprehensive recovery of iron and cobalt in the ore. The research shows that the iron?s grade is 61.23%, Co?s grade is 0.02%, the ore is rich iron ore and its Co content also reaches border mining grade. For the ore, if want get high grade iron concentrate powder, must identify the mineral composition and the occurrence of iron and take into ac-count the recovery of Co content as associated resources. Chemical phase analysis results show that 86.35% of iron exists in magnetite, which means that the theoretical recovery ratio of iron is close to 86%. Minerals spectrum analysis confirmed that the magnetite containing a small amount of Mg, Al, and other impurities, the actual iron minerals to 70.28%, which means that theoretically iron grade iron concentrate only close to 70.28%. Based on the result of iron chemical phase analysis, by investigating the liberation of sulfide minerals and gangue, the recovery index of iron can be forecasted, when grinding fineness is 35%, 45%, 55% and 65% bellow 0.074mm,theoretical content of Fe in iron concentrate separately is 67.71%,67.88%,68.78%,and 69.43%,accordingly the theoretical recovery of Fe is 87.38%,87.05%,86.92% and 86.63%. From the perspective of process mineralogy, the forecast mineral beneficiation indicators show that the ore is easy sorting ore, iron processing operations have higher recovery rate, but wants sorting of high-grade iron ore concentrate still need appropriate grinding fineness. Furthermore, associated element Co, existing mostly in pyrite and pyrrhotite, is valuable in the ore. Pyrite and pyrrhotite have ideal liberation under grinding, so cobalt can be easily enriched in sulfide concentrate.

Jan 1, 2014

By B Hannah, M Uriarte, F Labarca, C Madore, G Ganapathi, L Martin, T Haase

BechtelÆs Mining and Metals projects across the globe are executed in remote arid and semi-arid countries where providing even basic water supplies impose considerable challenges. Opportunities for water conservation measures using a Six Sigma initiative were proactively pursued to address the potential business impacts of limited availability of water resources. The initiative investigated areas driving water-optimisation during concrete operations and camp management. This paper details the water conservation evaluation of alternatives and cost/benefit analysis based on current and predicted water usage for development projects. Optimisation of water consumption through institutionalising more prescriptive standards for camp design and defining water conservation requirements have resulted in a new standard specification. Based on our projected mining project workload across the globe, it is estimated that for the period 2012 - 2015, a potential 5.5 M m3 water savings resulting in US$11 M could be realised for construction camps and savings of 4 M m3 of peripheral concrete process water resulting in potential cost savings of US$8 M could be achieved as a result of these revised standards.CITATION:Haase, T, Hannah, B, Ganapathi, G, Martin, L, Madore, C, Labarca, F and Uriarte, M, 2013. Water conservation at construction projects, in Proceedings Water in Mining 2013 , pp 251-258 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 26, 2013

By Norman L. Wimmler, H. G. Iverson, S. Ricker, P. E. Oscarson, S. H. Lorain

THIS paper has been prepared with the principal objective of recording the results of the Bureau of Mines exploration of five major clay deposits in the Western Region. It is based mainly on data contained in unpublished Bureau of Mines reports. Acknowledgment is made to the Federal Geological Survey for its cooperative work with the Bureau of Mines, to the various State geological and mining departments, and other State and local agencies. CLAY EXPLORATION BY THE BUREAU OF MINES Much has been written and published on clays and clay deposits relating to their refractory, ceramic, and other qualities but such literature is lacking in analyses of the available alumina content of the clays and provides little indication of their possibilities as a source of alumina. With this new objective in view, a great many of the known clay deposits were reexamined and new ones discovered. The Bureau of Mines made preliminary examination of numerous areas in the western United States. Five of those most favorably indicated were systematically drilled, and in each a large amount of high-alumina clay has been found. These five major projects are Molalla and Hobart Butte, in western Oregon; Cowlitz-Castle Rock, in southwestern Washington; Lone, in California; and the Olson-Troy area in Idaho (Fig. I). Preliminary scout drilling was done in the Stockton deposit at Coeur d'Alene, Idaho; the Whiteware deposit near Lewistown, Mont.; and 13 areas in the Spokane or eastern Washington region, where the most favorably indicated area, known as the Excelsior, is now being drilled more systematically. Preliminary drilling was undertaken in numerous areas adjacent to the major deposits and others more remote. As a result, large additional clay possibilities were found. THE CLAY DEPOSITS The clay deposits under consideration are of the sedimentary or transported types, parts of which have been altered further by the agencies of weathering, ground water, or hydrothermal action. There are extensive deposits of residual clays in northern Idaho and in eastern Washington, but they have been found to be low in the available alumina and to contain much free quartz, mica, and unaltered feldspar. To be of value, they must first be subjected to beneficiation to remove these gangue minerals. The sedimentary clays have been derived largely from the decomposition, erosion, and transportation of granites, gneisses, schists, and basalts. At Molalla, some

Jan 1, 1944

By Clarence Karr

In 1955 the Federal Bureau of Mines established a low-temperature tar laboratory at its new Appalachian Experiment Station in Morgantown, W. Va. The objective of the laboratory is to investigate the yields and chemical and physical properties of tars from low-temperature carbonization of coal, to investigate means of economically upgrading these tars, and to make available to industry and the public essential data for increasing coal utilization through the establishment of a new coal-chemical industry, based on the utilization of low-temperature tars. Because of the obvious economic significance of phenols, as well as the relative ease with which they can be separated and analyzed, initial research has centered mainly around this class of tar constituents. It was realized early that no listing of phenols and their physical properties existed that included enough compounds to be practicable. The purpose of this paper is to make such a compilation available.

Jan 1, 1957

By D. D. Rodier

Most zinc concentrates contain some silver and varying amounts of such valuable trace elements as gold, indium, germanium and gallium. With increasing similarities in plant installations, the predominance of electrolyte process and the increasing environmental constraints on iron disposal, it is essential that zinc smelters optimize the recovery of any valuable elements in their feed stocks. The process options, to date, of smelting, flotation or leaching of silver-rich leach residues cannot be applied economically to all installations. It is therefore necessary that new innovative processes, to recover silver and other valuable metals from relatively low grade feeds, be developed. This paper attempts to place this strategy in the context of today's constraints and will also provide a simple evaluation tool for any process alternatives.

Jan 1, 1990

By William C. Cooley

This volume contains copies of the 5 x 8 in. accession card file for all items collected which were judged to be relevant to underground hydraulic coal mining. In many cases, abstracts are included. Abstracts were taken from the source, from other reviews, or from the preliminary screening of Russian documents performed by Dr. A. L. Brichant. No attempt was made to write abstracts for every accession item.

Jan 1, 1975

By H. Kenworthy, M. M. Fine

The progress made to date in the mineral dressing of complex Arkansas titanium ores is reported in this paper. Concentrates of rutile, a dioxide of titanium, were produced by treating a submarginal ore from the Magnet Cove Rutile Co., Inc., Magnet, Ark. The rutile recovery at present is 45 to 50 pct of the total TiO2 with the possibility of increased recovery with additional research. The work reported herein is part of a general study which will later include results of investigation of other titanium ore bodies in the Magnet, Ark., area. The fragile character of the rutile minerals, the softness of the gangue, the occurrence of pyrite and leucoxene, and the considerable proportion of extremely small size rutile in the presence of montmorillonite- and illite- type clays in the Magnet Cove open-pit mine are the important factors in the mineral dressing of this submarginal rutile ore.

Jan 1, 1949

By C. E. Lesher

Two processes for agglomerating fine sized ores with low temperature coke are described. One process (Orcarb) agglomerates ores with limited amounts of carbon; the other (ore-carbon pellets) pelletizes fine sized ores, using low temperature cokes as the binder. Data are presented on the products obtained when taconite, magnetite, and hematite concentrates and several titanium oxide ores were used. REDUCTION of finely divided oxide ores has long been a major metallurgical problem. Various methods of agglomerating, notably briquetting, sintering, nodulizing, and pelletizing, have been developed and are in industrial use. Carbon is the usual reducing agent for oxide ores and attempts have been made to agglomerate fine ores with coking coal in order to get the metallurgical advantages of intimate contact and increased particle sizes suitable for subsequent smelting or reduction.1-3 For the past three years, research has been in progress on two processes for combining fine sized ores with reactive carbon in the form of low temperature coke. By one process, designated Orcarb, the ore is coated with coke carbon in amounts limited to that required for reduction and the result is an appreciable but limited increase in product particle size over that of the original ore. The second process, called ore-carbon pellets, produces pellets of fine ore bound by low temperature coke. The first objective was to develop a process for combining an oxide ore with only enough carbon for its reduction, the amount being that derived from the simple reduction equations. The carbon (that amount theoretically required for the reduction of the oxides in an agglomerate with ore), calculated to CO, ranges from 10 pct for zinc calcines or phosphate ores to 21 pct for rutile and 26 pct for silica. The carbon required for reducing iron oxides falls between the extremes—10 and 26 pct. When the carbon in the agglomerate is low temperature coke, reduction by hydrogen may be expected to take place, thus modifying the calculated carbon require- ment. On the other hand, in practice, an excess of reducing agent over that required in theory is normally used. Screen sizes of three iron ores on which the greater part of the experimental work was performed are given in Table I. Most of the testing was done with Freeport (Renton Mine) coal, but Pittsburgh and Elkhorn bed coals were also used. The first objective was to agglomerate the ore with sufficient low temperature coke to provide carbon for reduction, i.e., in the range from 10 to 25 pct. This was accomplished by preheating the ore, mixing with pulverized coking coal, and completing the coal carbonization in a plain steel rotating retort. The pilot retort, as it is now constituted, is shown by diagram in Fig. 1 and photograph, Fig. 2. Ore is fed into the upper kiln by a screw; it is heated to 900" to 1100°F by direct flame and it is then discharged into an insulating hopper from which it goes

Jan 1, 1956

By I. F. Avery

The productive capacity of natural-gasoline and cycling plants in the United States on January 1, 1958, was 48.8 million gallons per day, according to the Bureau of Mines biennial survey. This represented an increase of 2.4 million gallons per day during the 2-year period since the last survey. In the previous 2-year period, capacity had increased 7.5 million gallons per day. The major increase in operating capacity occurred in Texas and New Mexico. In New Mexico, capacity increased 43 percent. The total number of plants decreased from 600 on January 1, 1956, to 584 on January 1, 1958. The number of operating plants decreased from 571 to 558. Five new plants were completed in Colorado, increasing the number of operating plants from 7 to 12.

Jan 1, 1958

By J J. Laas, A J. S Spearing

Considering the capital outlay, running costs and inherent difficulties of backfilling operations at depth the benefits need to be clearly established, quantified and then exploited. Expansion of Vaal Reefs Exploration and Mining Company towards even deeper, highly faulted ground, and the process of establishing codes of practice for the management of rockfalls and rockbursts, required that a sound support strategy be formulated. This paper describes the derivation of an overall backfilling strategy on Vaal Reefs. Use was made of experience gained over some 12 years with backfilling. Numerical modelling was used to estimate potential benefits of backfilling the deepest mining areas still to be extracted. In exploiting a probably unique opportunity, two contiguous mining areas bounded by the same major geological structures, were compared. One was extensively backfilled and the other not at all. Shaft sinking through a backfilled stope added another dimension to the database.

Jan 1, 1998

By Carl R. Christiansen

The primary objectives of this project are (1) the determination of manpower demand in primary lead and zinc production for the years 1985 and 2000, and (2) the estimation of the availability of the required manpower for these years. In order to meet the first of these objectives relationships between employee requirements and metal production in the various states were established, The total primary lead and zinc production from United states mines in 1985 and 2000 has been predicted by the U.S. Bureau of Mines. These forecasts and the 1974 figures are as follows: [1974 1985 2000 Lead metal, tons 669,000 700,000 900,000 Zinc metal, tons 494,000 585,000 995,000] Mining By analysis of ore reserve data and industry characteristics, the authors estimated the portion of the primary production which each state would yield in the future years. As manpower requirements are determined by the tons of ore produced and by worker productivity, these figures were determined for each mining state and district by developing relationships between lead and zinc metal production, ore production, ore to recoverable metal ratios, employee productivity, and number of employees required. The number of new employees required annually to compensate for attrition and production growth is provided, also.

Jan 1, 1975

By K. Bunney

A high-pressure laboratory elution rig was commissioned to simulate industrial Zadra and AARL elution conditions for the stripping of gold, silver and mercury from loaded activated carbon. It was found that cyanide was essential for the efficient elution of both mercury and silver, while gold was found to elute most effectively in hot, low-ionic strength solutions. Therefore, the standard AARL-type elution, which implements a cyanide soak and water elution, results in a lower recovery of mercury and silver from the carbon. No single set of conditions was found whereby gold, silver and mercury can all be effectively eluted in a single step. However, sequential elution conditions can efficiently recover all metals and provide a potential approach for separating these metals.

Jan 1, 2010

The Institute conducts jointly with the American Society of Civil Engineers, American Society of Mechanical Engineers and American Institute of Electrical Engineers, certain activities as listed below, and is joint owner with them of certain properties situated at 29 West 39th Street in New York City United Engineering Trustees, Inc. When Mr Carnegie made his gift, "for the erection of a suitable union home" for the engineering societies, United Engineering Trustees, Inc (then United Engineering Society) was chartered un¬der Chapter 703, Laws of the State of New York, 1904, for "the advancement of the engineering arts and sciences in all their branches, and to maintain a free public engineering library " The Corporation was further empowered to acquire real and personal property and to use, maintain and occupy it, with the provision that any building erected by the Corporation shall be used perpet¬ually as a meeting place and headquar¬ters for the Founder Societies Thus the Carnegie gift realized the ideal of bring¬ing the engineering societies together under one roof, and the Corporation through its members nominated in equal numbers by the four Founder Societies had the necessary authority to act for the Founder Societies in their joint in¬terests in owning and operating for them not only Engineering Societies Building, but in the course of time, Engineering Societies Library, and The Engineering

Jan 1, 1952

By A Winchester, D Grant

The massive 1100 Orebody in Mount IsaÆs X41 Copper Mine has been extracted over the last 40 years form north to south utilising sublevel open stoping methods.De velopment has continually stepped ahead of production to provide access to new primary stoping blocks. The remaining secondary pillars contain stopes with one, two or three fill mass exposures and were constrained by access requirements and stope extraction turnaround time.The remaining southern mining areas consist of large 40 m wide by 300 to 400 m long east-west transverse pillars that have been left to provide access for ventilation and service requirements. Three large transverse cross-cuts or transverse pillars û 4180 x/c, 4010 x/c and the Panel pillar now remain. The 4180 x/c was the last major transverse pillar to be successfully broken.This transverse pillar is being extracted in a retreating sequence, creating 3SLOS stopes due to the surrounding backfilled stopes.In recent years the extraction of the first, and most critical, stopes in the transverse pillars have resulted in large changes to the induced stress field. This paper describes the extraction of the 1.1 million tonne stope P418 in the 4180 x/c pillar.T echnical challenges that were faced and how they were overcome to allow for the successful extraction of the stope are described.Critical to the success of the P418 stope extraction were the rehabilitation methodology used; extraction strategy modifications to address deteriorating ground; mass firings with multiple directional changes; managing the exposure of backfill of variable strengths; and geotechnical monitoring prior to, during and after extraction.

Jan 1, 2005

By H. R. Bullis

Lupin is located on the shores of Contwoyto Lake at lat. 65° 48'N, Long. 111° 15'W and lies about 80 kilometers south of the Arctic Circle. Since start up in 1982 the mine has produced over 2.15 million ounces of gold from 6.66 million tonnes of ore grading 10.63 gm/tonne. Total remaining reserves at 1993 year end were 5.1 million tonnes at a grade of 9.11 gm/tonne (1.65 million ounces). This is sufficient for 7 -8 years at the present annual production rate of about 200,000 ounces. The Centre and West Zones of the deposit are open to depth. The deposit is in an Archean metaturbidite sequence of the Contwoyto Formation, which has been mapped as part of the Yellowknife Supergroup of supracrustal metasedimentary and metavolcanic rocks making up part of the Slave Geologic Province. These rocks have been subjected to regionar and contact metamorphism and to several phases of deformation. Six stages of Archean plutonism have been identified and all Archean rocks have been cut by Proterozoic diabase dyke swarms. Gold mineralization in the Lupin deposit is commonly fine grained and associated with pyrrhotite and arsenopyrite in amphibolitic banded iron formation. The gold-bearing portions of the host iron formations are characterized by the presence of multiple quartz veins and the pervasive replacement of grunerite by hornblende. In sparsely mineralized portions of the host iron formation, zoning of sulfides about quartz veins is clearly seen with the arsenopyrite halo being more restricted around the veins than the pyrrhotite halo. In well mineralized portions, quartz vein densities approach one vein per metre along strike. In these areas pyrrhotite distribution in the iron formation is more pervasive and the rock takes on the appearance of a banded sulphide rock.

Jan 1, 1995