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By Bradford F. Townsend, Matthew E. Fowler, Michael F. Smithson, Lawrence R. Eckert

All Rights Reserved. Printed in the United States of America. Information contained in this work has been obtained by SME, Inc. from sources believed to be reliable. However, neither SME nor its authors guarantee the accuracy or completeness of any information published herein, and neither SME nor its authors shall be responsible for any errors, omissions, or damages arising out of use of this information. This work is published with the understanding that SME and its authors are supplying information but are not attempting to render engineering or other professional services. If such services are required, the assistance of an appropriate professional should be sought. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of the publisher. Any statement or views presented here are those of the authors and are not necessarily those of SME. The mention of trade names for commercial products does not imply the approval or endorsement of SME.

Dec 1, 2010

By J P. Sykes, A Trench

"The common-held view of the future of copper mining is one of declining quality of mineral resources and increasingly limited long-term development options. This decline, in turn, is viewed as inevitably leading to increasing economic, socio-political and environmental costs. As a result, new technologies and innovations will be required to mitigate cost escalation. The future is therefore typically summarised as a battle of a ‘below-ground’ declining quality asset base pushing costs upward versus ‘above-ground’ technology and innovation driving costs downward. The role that high quality new mineral discoveries could play in mitigating industry cost pressures is typically understated, if considered at all. New high quality discoveries can be mined at lower cost than existing assets and potentially if discovered in the right locations within a more amenable contemporary environmental and socio-political setting. Such deposits, once discovered, would improve the overall quality of the industry asset base, as well as benefitting their owners substantially through higher margins. However, to target new high quality deposits explorers need some understanding of the nature of high quality copper mines in the long-term future. Conventional scientific and economic techniques for analysing the future of copper supply, generally by studying the project pipeline, ignore as yet undiscovered resources and also struggle to fully incorporate the multiple internal and external factors that could impact upon copper mining practices in the future.Scenario analysis is specifically designed to consider multiple factors interacting in the future, and is thus more creative than simply looking at the visible project pipeline. The use of scenarios is therefore potentially capable of providing insight into aspects of the future of copper mining about which little is currently known or that remains considerably uncertain. In this study, the Oxford University Scenarios methodology was employed to analyse different plausible futures for copper mining and the consequent implications for exploration targeting strategies. The scenario analysis highlights two key dimensions or axes that serve to map out potential industry futures: firstly the technical and economic optimisation of the existing industry; and secondly the generation of new prospects or ‘search space’ for the copper industry. These two axes in turn frame four different scenarios for the future of the copper mining industry. These copper mining scenarios are then compared to the 20 largest existing copper mines and projects, and their owners, to determine if any represent an appropriately robust exploration targeting proxy: none do. The paper therefore concludes that efforts by industry are required to generate mine concepts that would be viable across all scenarios, and thus act also as exploration targeting proxies. In the interim, companies will have to seek to build portfolios that create an overall robust asset base, out of individually less robust assets. Failure to do this implies that consequential, irreversible strategic decisions lie ahead for the copper mining industry, which may be a threat to both incumbents and the very industry itself. This situation makes strategic exploration targeting in the copper industry very difficult.CITATION:Sykes, J P and Trench, A, 2016. Using scenarios to investigate the long-term future of copper mining and guide exploration targeting strategies, in Proceedings International Mine Management Conference, pp 265-290 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jun 22, 2016

By David A. Neudorf

Known resources of nickel laterites considerably exceed nickel sulfide resources and there is a growing consensus that most new nickel production will be sourced from laterites. The development of nickel laterite projects is very capital intensive due to inherently low grades, inability to concentrate ore prior to processing, complex processing technology and typically large infrastructure requirements. This has resulted in most recently proposed projects being "mega-projects," to achieve economics of scale. However, this may result in unacceptable project risk in many cases. Furthermore, many known laterite resources are not large enough to support a mega-project. This paper describes an alternative model for nickel laterite project development that allows, smaller scale and reduces capital exposure. The requirements of this model in terms of process technology, infrastructure and commercial innovation are described. Keywords: Nickel, Laterite, Project, Economics

Jan 1, 2004

By Andrew Scogings

The current edition of The Australasian Joint Ore Reserves Committee (JORC) Code was published in 2012 and, after a transition period, the 2012 edition came into mandatory operation on Dec. 1, 2013. There is a significant change between JORC 2004 (Clause 44) and JORC 2012 (Clause 49) for the reporting of industrial mineral resources and reserves, which should be addressed by ASX-listed players in the industrial minerals space.

By James G. Lyons

All machines vibrate and make noise. An increase signals impending trouble. Vibration and noise analysis allows the condition of the machine to be determined without costly interruption in service for disassembly and physical inspection.

Jan 1, 1977

In October, the Aluminum Company of America restarted the fourth of seven pot-lines at its Point Comfort, Tex. primary aluminum smelter. The price of primary aluminum ingot, as quoted by American Metal Market, was increased from a range of 60.5 to 63.0 cents per pound at the end of September to a range of 66.0 to 66.5 cents per pound at the end of October. BERYLLIUM On October 15, Brush Wellman, Inc., of Cleveland, one of two U.S. producers of primary beryllium products, announced a planned $6 million expansion of its extraction plant at Delta, Utah, increasing the plant?s capacity to extract beryllium from bertrandite ore by 25%. Another $5 million will be spent on two mine expansion programs in Jaub and Millard Counties, Utah. Other mineral claims and 1 eases he 1 d by The Anaconda Company will be taken over by Brush Wellman through lease or purchase. This expansion, when completed in 1981, will decrease U.S. dependence on imported beryl ore.

Jan 1, 1979

By C. Yi, M. Onifade, B. Genc, S. Dineva, T. Zvarivadza, M. Khandelwal

Deep hardrock mines worldwide increasingly face rockbursts as mining depths increase. These events result from the accumulation and sudden release of stress, causing rockmass damage and posing major safety and operational challenges. This paper focuses on destress blasting as a critical strategy to mitigate rockburst hazards. Although limited practical experience exists in Swedish deep hardrock mines, international case studies demonstrate that, when well implemented, destress blasting redistributes peak stresses by promoting controlled fracturing around mining excavations. The success of such techniques is highly dependent on site-specific factors such as stress regime, rockmass brittleness, structural geology, and blast layout. Although destress blasting is especially effective in massive, brittle rock under high stress, typical conditions for strainburst prone environments, its design cannot rely solely on numerical models. Simulations can offer preliminary evaluation of stress redistribution trends and guide early design assessments but their current limitations, including sensitivity to input data and simplified fracture mechanics, mean they are best used as supplementary tools rather than final decision-makers. Field trials, supported by microseismic analysis and fracture mapping, remain essential for validation. The study critically synthesises international experiences and presents a structured framework for destress blasting design, offering practical and academic perspectives aligned with Swedish geological conditions to support safer and more efficient application in deep hardrock mines.

Jun 27, 2025

By Jr. Gabler

Methods for the direct spectrochemical determination of impurities at the parts-per-million level in tungsten metal and oxide are presented. Several published procedures were investigated and numerous modifications were made in establishing procedures with improved precision and extended lower levels of determinability. Details of standards preparation are presented, experimental work is described, and three preferred methods are described in detail. A germanium carrier-distillation procedure is applicable to the determination of 13 elements in tungsten powder; a silver chloride carrier-distillation procedure provides for the determination of 24 elements in tungstic oxide, and a sustaining ac arc method is applicable to 26 elements in tungstic oxide. The choice of methods to be used depends upon sample form, elements and concentrations to be determined, and the precision and accuracy required. The investigations reported here were undertaken to develop direct spec-trochemical methods with increased accuracy and precision to determine impurities in high-purity tungsten and tungstic oxide, to define the lower concentration levels of detectability and measurement for the common impurities in tungsten by direct spectrographic means, and to present the details of the developed or modified methods that have proved applicable.

Jan 1, 1965

By John Mathews

IT is a great honor to be asked by. the Board of Directors of this Institute to deliver the Henry Marion Howe lecture. The invitation carries with it a great responsibility, which I accept with considerable hesitation and with a feeling of unworthiness to perform the duties expected of me in this hour devoted to the memory of the life, character, and work of the late Professor Howe. Many of you recall the scholarly address delivered here a year ago by Prof. Albert Sauveur, and the beautiful tribute he paid-to his friend and colleague of many years in the great work of changing the art of iron making into the science of iron. My association with Professor Howe, was of brief duration-only one year-and the relation was that of pupil to teacher. My feeling toward him in later years was always that of a humble disciple at the feet of a master. He attained his third academic degree in the year that I was born. I recall the pride I felt when, after entering the, steel industry, I received from him, from time to time, letters asking for information or, perchance, asking my opinion, and he was always most punctilious in acknowledging the source of such bits of information in his writings. It was also my good fortune to sit at the feet of another great teacher-Sir William Roberts-Austen, at the Royal School of Mines. I mention him because his name was used by Osmond in coining the word "austenite," which is the subject of this address, and Osmond's suggestion was heartily approved by Howe. These three international metallurgists were the best of friends and delighted to honor the achievements of one another. There are other reasons for mentioning Roberts-Austen at this time. It was an introduction from Howe that opened to me the door of his -laboratory as well as of his heart. It was while at Roberts-Austen's laboratory that I .worked side by side with William Campbell

Jan 4, 1925

By Henry S. Washington

Introduction. It Still Rains On The Choco ! I Well Remember One Evening A Dozen Years Ago, While. Traveling Toward The Town Of Negua In A Small Champa Or Dug-Out Canoe, The Rain Fell So Heavily That I Had To Work My Hardest To Bail Out The Water With A Large Totuma Or Gourd In Order To Keep The Canoe Afloat, The Senegambian Meanwhile Plying His Paddle In The Stern. If Any One Thinks Bailing Is Easy Work, Let Him Scoop Out A Quart Or More At A Stroke, 40 Times A Minute For Half An Hour, And I Venture That He Will Change His Opinion. These Small Canoes Required Only One Paddler, To Make The 3 Miles An Hour Which Is The Standard Rate Of Aquatic Progress On The Choco. Another Time, On The Atrato River, About Six O'clock In The Afternoon, The Rain Fell So Heavily Than An Empty Gourd, 9 In. In Diameter And 4.5 Deep, Was Filled To The Brim In 90 Sec., Timed By A Watch. Such Downpours Are Typical, But Unless Caught In One It Is Not Specially Noticed. These Downpours Seldom Last More Than An Hour, And Frequently Cover Only A Limited Area, Occasionally Falling On One Bank Of A River And Not On The Other. During The Night-Time,' The Rain, If Gentle, Will Usually Last Until Dawn, And Sometimes An Intermittent Drizzle Will Keep Up All Day As Well, Although, As A Rule, It Rarely Rains During The Day. The Rise Of The Rivers, Due To The Rain-Fall, Varies From A Few Inches To Several Feet. One Night In August, 1899, The Spuds Of The Dredge Margaret, Operating On The Atrato River, Showed A, Rise Of 16 Ft., And For 3 Days Thereafter Occurred The Greatest Flood Known In That District For 32 Years. The Dredge Had All Three Spuds Clown, And The 2-Yd. Shovel Dragging On The Bottom. A 0.75-In. Cable Fast To A Stout Tree, 700 Ft. Away, Stretched Tight

Sep 1, 1908

By Hal J. Kelly

A number of problems that developed in processing the halloysitic clays of eastern Washington and northern Idaho were investigated by the Bureau of Mines. The deflocculating effect of tetra sodium pyrophosphate is compared with several other compounds, and on the basis of current theory, the advantage of sodium pyrophosphate as a deflocculating agent is explained. The adsorption of the sodium ion by clay in a clay"-water system was established by a radioactive tracer technique, and the deflocculating action of sodium pyro- phosphate was postulated. The effective dispersion of the halloysitic clays was limited by the occurrence of tightly bound aggregates of small, individual crystals. Disaggregation of the agglomerates was investigated by liquid extrusion and ball milling of dilute slurries and by extrusion of the clay in a plastic state. The greatest increase in the production of small particles was by high? pressure liquid extrusion.

Jan 1, 1963

By S Worden, A Lee Zhi Yi, E Sellers, G Corder, A Littleboy

The global shift towards decarbonisation is driving competition for the extraction of critical minerals such as nickel, lithium, and copper. To meet this demand, new mines are being developed while mines approaching closure are being reimagined as sites of potential resources. This reimagining challenges how mine closure is being conceptualised. In the conventional case, when a mine reaches the end of its economic life, it is closed or put into care and maintenance until it transitions to the next land use, such as agriculture, native ecosystem corridors, solar farms or integrated eco – precincts (Murphy et al, 2019; Holcombe, 2020) (the authors acknowledge that unplanned mine closures have left a devastating legacy of contamination, safety and cultural heritage impacts). Extracting minerals from closed or closing mines will extend mine life and, therefore, delay relinquishment and transition. In this context, innovative technologies are needed to make mining economically viable. In the first year of her doctoral research on improving stakeholder engagement in mine transitions, Lee Zhi Yi has coined the term ‘mine life extension technologies’ (MLETs) to describe a class of technological solutions that optimise extraction of resources after a mine reaches the end of its economic life. Examples of MLETs include agromining (van der Ent et al, 2015), in situ recovery (Robinson and Kuhar, 2018), and reprocessing or reuse of tailings (Gou, Zhou and Then, 2019). MLET extraction offers several benefits compared with conventional mining processes, such as waste remediation, value recovery of minerals, a smaller footprint and less environmental impacts (Sellers, Picorelli and Salmi, 2022). What requires further investigation is the consequences of MLET implementation to host communities or community perspectives towards the proposed technology and subsequent delays in transition.

Aug 2, 2023

By Linda L. Chasko, Charles P. Lazzara, Gary Braselton, Ronald S. Conti

Preparedness is an important element of any underground mine's strategic plan in dealing with an unexpected event, such as a fire. A fully implemented fire preparedness and response plan is essential in reducing the probability and seriousness of a mine fire. This report describes the development of an underground coal mine fire preparedness and response checklist (MFPRC). The checklist is a data collection instrument for profiling both the fire prevention and response capabilities of a mine site and usually requires 3 to 4 days to complete. The checklist encompasses conditions, procedures, and equipment that have frequently been identified as the primary or contributing causes of underground coal mine fires. At least 1 day is needed underground to evaluate the water system. This entails measurements of water flows and pressures at fire hydrants, and water throw distances of fire hose and nozzles at several locations (mains and branch lines). A few of the other topics that are discussed with mine personnel include detection and suppression systems, combustible materials, mine rescue and fire brigades, and firefighting equipment. The MFPRC was developed by the National Institute for Occupational Safety and Health (NIOSH),Pittsburgh Research Laboratory. Under a Cooperative Research and Development Agreement (CRADA) with Cyprus Amax, Twenty mile Coal Co. (Oak Creek, CO), the checklist was field tested and further refined. Additional field tests were conducted at several other operating coal mines.

Jan 1, 2000

By William L. Young

There is an old saying in Canada: "Mines are made as much as discovered." What follows is Young's perception of his experience developing and financing the Cochrane Hill gold mine project. In 1974, I came back from rutile and zircon exploration and mining in Australia. I became interested in a copper, lead, and zinc project in the Bathurst District, New Brunswick. Much field work had already been done but I was convinced that a reinterpretation of the geophysical work left room to enlarge on the known mineralization. So, with my own money I put a property deal together, found an underwriter willing to raise $100,000, and had a lawyer produce a prospectus. The prospectus was ultimately accepted for filing by the Ontario Securities Commission and I acquired funding and began work. It did not take many drill holes to determine that the interpretation was not geologically valid. However, while drilling was going on, geophysical and geochemical explorations indicated interesting anomalous zones elsewhere on the property. But by now the base metal market climate had soured and the $50,000 I had left was not enough to evaluate the new results. So I decided to farm out the property. A data folio was produced and the property was optioned to a major mining company, with Northumberland Mines Ltd. retaining a 20% free, carried interest. By 1976, the market for junior issues was so bad no under¬writer would even talk to a geologist and I still had the $50,000 in the bank and was looking for something to initiate. A Project That Went Nowhere Market research indicated that the Toronto area imported fine calcium carbonate fillers from Georgia, Alabama, and Vermont. I was aware of the specs and the fact that there is a large marble belt in Eastern Ontario. After some prospecting, I found an interesting deposit. The product was slightly high in silica and low on brightness. Research work eliminated the silica and corrected the brightness. So, with insufficient money we launched a feasibility study. This included diamond drilling, bulk sampling, special fine grinding and air classification tests, and an in-depth market survey. Our product was as good or better than those on the market. Our advantage was that delivery could be made by a two-hour truck haul to the customer. The present system of rail delivery had many problems, especially in winter. Despite everything looking rosy, we ran into a stone wall. The underwriters were singularly unimpressed because the public saw little glamour in a substance most people had never heard of. The issue would have been difficult-if not impossible-to sell. Banks and government agencies took the position that if we could get long term take-or-pay contracts then they would lend the required capital. None of the suppliers, however, would even consider a contract until production had begun and they could evaluate the production material. It was a classic "catch 22" situation. I have gone into this in some detail to show how tough the industrial mineral market can be. We eventually optioned this calcium carbonate property to a major corporation. The option agreement would give us a free, carried 15% and the right to buy up to 40% for contributing 25% of the production costs. But the experience left my company in poor financial shape. To survive, I think the entrepreneur-geologist must always have at least one project in reserve, an emergency plan. I had been searching out a new project to work on, after the calcium carbonate option was wrapped up. It was gold. Gold intrigued me and I knew quite a bit about Nova Scotian gold. I felt that with any rise in price, many of the former high-grade gold mines would have interesting potential for the larger, low grade portions of the deposits. That is how I happened on Cochrane Hill, where much work had been done in the early 1970s when gold as $4.82/g ($150/ oz). This time my timing was good. No sooner had Northumberland signed an option agreement than gold prices started to rise. In six months, they went to $27.331g ($850/oz). Even so, financing gold prospects in early 1980 was still not easy. It had been years since gold financing had been undertaken. A whole new generation of investors, with no knowledge of gold mining, had grown up. So, with accounting and legal council, we decided on a semiprivate "seed money" offering. Under the new Ontario Securities Act, this was a new-and partly tax sheltered-concept. At the time, it was very innovative.

Jan 6, 1982

By K. J. Ladwig

The Bureau of Mines conducted a field investigation of the water quality in inundated underground coal mines in the Northern Anthracite Field, eastern Pennsylvania. Water samples were collected at multiple depths from nine abandoned mine shafts in the Wyoming Basin, ranging from 68 to 650 m (223 to 2,132 ft) in depth and intersecting as many as seven mined seams in a single shaft. The shafts were also monitored for fluid resistivity, fluid temperature, Eh, and pH using downhole instrumentation. The monitoring program showed that the formerly highly acidic mine water is now slightly alkaline. Sulfate concentrations decreased as much as 74 pct in the flooded workings and 54 pct at a mine water discharge from values reported in 1964 and 1968, respectively. These data are consistent with the inhibition of pyrite oxidation and gradual flushing of oxidation products in flooded mine environments. The monitoring program also revealed significant vertical stratification in water quality in five of the nine shafts, each characterized by two easily recognizable zones. The transitions between zones were sharp, marked by rapid changes in Eh, pH, and ionic composition, the upper zones being less contaminated than the lower zones. The development of stratification appears to be a function of shallow localized flow conditions, arising primarily from the relative positions of mine openings and structural features of the coalbeds.

Jan 1, 1984

The value of U.S. mineral raw material output reached a record $63.1 billion in 1975. This high exceeded the 1974 value of $55.2 billion by 14 percent. Among the three major mineral categories -fuels, metals, and nonmetals -only fuels showed an increase in value. Both the metal and nonmetal categories showed declines in value. The significance of this nearly $63 billion mineral output can be noted in the fact that it is the basis for the subsequent production of over $270 billion a year in energy and processed materials. Of the 78 individual mineral commodities included in these 1975 totals, only 17 registered gains in output, while 45 registered value increases, reflecting higher prices.

Jan 1, 1976

By LESTER W. STRAUSS

FOR fifteen months after the other dominions of the British Empire and the entire so-called sterling 11loc loosed the shackles that bound the111 to the gold standard, South Africa, giant among gold-producing nations, remained stubbornly attached to gold at the traditional ratio of 85 shillings in currency to one ounce of gold. But eventually even South Africa had to heed the dictates of trade and the obvious interests of its great gold-mining industry. In December, 1932, South Africa's currency severed its golden bonds. Today the South African pound is 011 a par wit11 the British pound.

Jan 1, 1935

Study on Dynamic Characteristics of Inertia Cone Crusher and Its Application

Sep 13, 2010

This paper is an outline of the developmental practices now in use at North Broken Hill Limited, N.S.W. The description will be given under the following headings.I. General.......opening up of a new level.II. Driving.III. Winzing.IV. Rising.V. Auxiliary Ventilation.VI. Notes on the Introduction of Mechanical Appliances.VII. Office Records and Routine.I. GENERALThe lode, for purposes of description, may be said to be divided into two portions which are usually referred to as the Southern and Northern Orebodies.The southern ore-body is the larger and in places attains a width of 200 feet. The northern ore-body is, generally speaking, comparatively narrow. These ore-bodies have a northerly pitch of approximately 45' and a westerly dip of 60. In the southern ore-body a grid of ore chutes is provided at 31 ft. 8 in. (5 square set) intervals and this necessitates an elaborate arrangement of cross-cuts, portion of which have to be driven through the foot-wall. Crushed country rock adjacent to the foot-wall makes it necessary for drives to be placed at least 60 feet from the lode.In the northern ore-body the ore chutes are arranged along a longitudinal drive, thus making a much simpler layout. These layouts were described in detail by A. R. West (Proceedings A.I.M.M. No. 117). In opening up a new level from the shaft plat, a heading is extended in a westerly direction until a point approximately 60 feet from the footwall of the lode is reached.At this point the direction of the cross-cut is altered to a bearing approximately 90 to the general strike of the ore-body, and the cross-cut continued until the hanging-wall is intersected. From the information obtained together with that from diamond drilling, the outline of the ore-body is plotted as closely as possible, and this serves as a basis for the layout of the level. Drives south and north from the main cross-cut are made in order to determine the southern and northern extremity of the southern ore-body. The former is usually driven in the centre of the ore-body and serves as a permanent gangway and ventilation drive for the new level.From the northern extremity of the southern ore-body, the drive north is...

Jan 1, 1944

Duty on Lead Reduced. -On December 28, the President signed H.R. 5047 which reduces the duty on unwrought lead from 3.5% ad valorem to 3% ad valorem, with a floor level of 1.0625 cents per pound, effective retroactively from January 1, 1980, through June 30, 1983. Pacific Northwest Power Bill Passed. -On December 5, the President signed S. 885 which will enable the Bonneville Power Administration to guarantee 20-year contracts to its 15 major industrial customers in exchange for higher rates. In effect, the bill will have industrial customers pay some of the costs of building additional generating facilities in the Northwest, of which thermal units are expected to be a major part. BPA supplies power to six primary aluminum producers which operate eleven plants having over 30% of the primary aluminum capacity in the United States.

Jan 1, 1980