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By Cyril S., Smith

WE cannot but marvel at the fact that fire is necessary for almost every operation. It takes the sands of the earth and melts them-now into glass, now into silver, minium or other lead or some substance useful to the artist or physician. By fire, minerals are disintegrated and copper produced; in fire is iron born and by fire is it subdued; by fire, gold is purified; by fire, stones are burned for the binding together of the walls of houses.... Fire is the immeasurable, uncontrollable element, concerning which it is hard to say whether it consumes more or produces more." Thus wrote Pliny in his "Natural History," that great collection of fact and error which constitutes the principal contemporary description of Roman technology and which until the seventeenth century was the authority most often quoted and requoted by those who wrote on metals, as on many other subjects.

Jan 1, 1940

By Carl N. Anderson

This paper, which is one of a group presented by the United States Bureau of Mines covering mining practice in different districts, deals in particular with the methods employed in mining the horizontal type of zinc-lead orebodies of the West Baxter area of the Tri-State zinc and lead district. These orebodies, locally termed "sheet-ground" bodies, with their relatively low working faces and low tenor of zinc and lead, require changes in the mining practice which is used in the balance of the district. In addition to the general mining methods, this paper also describes the system of hand sorting employed prior to the direct milling of the ore. The Hartley mine is situated mile west of Baxter Springs, Kans., as indicated in Figure 1. Its general outline and the location of the shafts with respect to the milling plant are shown in Figure 2.

Jan 1, 1932

By S M. Stewart

Industry, especially extractive industry, must now give serious attention to the impact its operations have on the natural environment and on the economic, social, and cultural context within which it operates.   While this obligation is statutorily managed, there has been a recent shift towards a culture of self responsibility. Industry is now talking about earning its ôsocial licence to operateö and the importance of maintaining the ôtriple bottom lineö, thus adding environmental and social performance to the usual financial criteria used to measure organisational performance. The social context within which companies operate has also become more sensitive with industry responding to a growing public expectation that it conduct itself in a way that strives for sustainability by operating and developing in a way that meets the needs of the present without compromising the ability of future generations to meet their own needs.   There are glowing accounts of industries engaging and collaborating with the communities within which they are based. In amongst these are also some disasters which result from cultural assumptions, industry created dependencies and the failure to attain community buy-in despite significant investment by the industry involved.   There are also remarkable stories of communities, and action groups within communities, being a significant catalyst for positive change of their natural, cultural and social environment. In amongst these stories there are also accounts of long and drawn out battles; adversarial situations where no one wins; a litany of mistrust, tricks and tactics, with the better resourced party ultimately achieving its primary objectives at the cost of the other (and at the cost of any potential fruitful, mutual relationships).   So what makes the difference in achieving the positive rather than negative outcomes? The answer lies in the way the outcomes are achieved. Building relationships based on good communication, respect for divergent views, mutual understanding, and the development of trust and empathy, makes it possible to identify shared goals and objectives that best meet the needs of all parties.   Research indicates the mining industry is making good progress in developing policy and commitment to community development and engagement but that, ætranslating commitments into improved practices at the site level remains one of the industryÆs toughest challengesÆ. (Australian Government - Community Engagement and Development Handbook October 2006 @ page 49.)   This paper considers the merits of a process of community collaboration and what it has to offer in terms of meeting that challenge.

Jan 1, 2007

By Wm. L. Giachino

"Over the last 10 years, C-1-L has played a significant role in the major advances that have taken place in blasting technology, among them the following: development and introduction of capsensitive slurries; development of bulk slurry systems both for underground and open-pit operations; development of the TOE-DET and ANODET systems of delay blasting;introduction of the NONEL system of initiation;development of the Vertical Crater Retreat (VCR) system of mining.This paper identifies areasin which we foresee further developments in blasting technology over the next 10 years and outlines how and to what extent C-1-L will become involved."

Jan 1, 1980

By Cleveland Dodge

THE present organization of Copper Queen employ-ees, known as the Employees' Conference Com-mittee, is really an outgrowth of the former Grievance Committee, which, in turn, had developed from the original Hospital Committee. The relatively small membership of these older organizations, the practical limitation of their activities to the presenting of grievances, and their lack of initiating powers, were the principal defects which the plan now in operation seeks to overcome. A somewhat parallel scheme was instituted in our Sacramento Hill division about four years ago; this gradually developed into the Ways and Means Committee, which, in addition to providing a forum for the discussion of operating problems, was instrumental in establishing an excellent and mutually satisfactory bonus system. Before recommending adoption of the plan now in force, we made extensive inquiries among those who have had any experience in such matters, and ended by proposing a modification of a scheme developed by John Leitch,1 which was characterized by its similarity to the constitution of the Federal Government. As finally remodeled, the. plan was submitted to vote of the entire working forces at the Copper Queen mines, and was adopted by them in May, 1920. Mining opera-tions since that date have been so interrupted that it is scarcely possible to state exactly what the results have been. The following quotations are from a printed pamphlet containing the constitution of the organization, as finally adopted. The first extract is from a letter addressed by the management to the employees: The plan submitted for your approval and adoption is modeled after the constitution of our own country, under which every individual is given an opportunity for advancement, according to his ability and determination, and every citizen is given a voice in the laws that shall govern him. So it is to encourage the individual employee in advancement, and to give him a voice in making the rules that shall govern his conduct, that we favor the adoption of the proposed constitution.

Jan 1, 1923

By E. D. Fields, M. C. Tippett, S. W. Sayers

The Copper Canyon and Copper Basin properties of Duval Corp., in Lander Co., have been recently added to the list of porphyry copper mines in Nevada, marking the first new copper open pit operations in this state in 15 years. Ore is processed in the 4000 tpd flotation mill at Copper Canyon, with some copper being recovered by dump leaching. The ore from Copper Basin, 10 miles northeast of the Canyon, is trucked to the mill for concentration. Cost of developing the properties is estimated at $22 million. It was recognized at an early stage of exploration that the two deposits were quite different. Continuity, mineralogy and grade of ore are much more uniform in the Canyon than in the higher grade, pod-like deposits in the Basin. The fundamental difference between the two areas is that the Canyon mineralization is dominantly hypogene, whereas the Basin ores are secondarily enriched.

Jan 3, 1968

By Robert E. Murray

The title of my paper, "A Company's Response to Federal Coal Leasing," brings to mind a picture of a dog chasing its tail. This is what the coal industry, has been doing since the Federal coal leasing moratorium went into effect in 1971. We've gone around in many circles, but we are only very slowly, if at all, getting closer to catching our tails, i.e., efficient, economical, and rational Federal coal leasing. My companies, The North American Coal Corporation and its four Subsidiaries, The Falkirk and Western Plains Mining Companies and The Coteau and Missouri Valley Properties Companies, together hold in excess of 4.5 billion tons of lignite reserves in North Dakota. Some of our North Dakota properties are substantially interspersed with Federal coal, with the government holding title to the minerals in every other section. This checkerboard pattern of Federal ownership has made it difficult to develop and market some of our reserves, and, as a result, it has become imperative that we be familiar with and active in the Federal Coal Leasing Program.

Jan 1, 1982

East Nelson and Marlborough, in the northeast of the South Island, contain a wide variety of metallic minerals, including gold, silver, copper, chromite, antimony and scheelite, but no sustained metallic mining industry has evolved. Gold was the most sought-after mineral during the first century of European settlement and numerous discoveries were made but these failed to live up to expectations. While traces of gold are widespread in east Nelson, including in quartz veins in Nelson City, no payable deposits were found. In Marlborough the probability of a gold discovery had initially seemed remote but all this changed with the finding of rich deposits in the bed of the Wakamarina River in 1864, which provided a much-needed boost to the provincial economy. However, the decline of gold mining in Marlborough began virtually as soon as it had commenced. Extensive floods in 1865 hastened the exodus of miners to the profitable new fields of the West Coast.

Jan 1, 1993

By P Christen, D R. Ashley, G R. Power

The Ernest Henry Mine is currently a copper-gold open pit operation situated in north-west Queensland, Australia. It is owned and operated by Xstrata Copper with a current throughput of 11 million tonnes per annum; however, open pit operations are scheduled to cease in late 2011. The deposit dips at approximately 45¦ and extends for at least another 400 vertical metres below the final 530 m deep pit design. Resource drilling from 2002 until mid 2008 has enabled an Indicated Mineral Resource to be established to 1000 m below surface. Scoping and prefeasibility studies (PFS) have been completed toward determining if this resource is suitable for underground mining and a feasibility study is currently progressing with a sublevel caving (SLC) concept. This paper briefly describes the process by which the SLC method was selected, conclusions regarding the non-selected methods, and then discusses the optimisation process used to derive the mining plan. The key optimisation parameters include the production drive spacing, level spacing, draw strategy, cut-off grade and production rate. Key risks will then be assessed and economic sensitivities studied. Final sensitivities will use Monte Carlo simulations to improve the transparency of the projectÆs risk profile. The feasibility study (FS) began in March 2008 and this paper describes the main optimisation steps at the time of writing and outlines the plan for study completion through to March 2009.

Jan 1, 2009

By George M. Leonard

Mineral commodities on National Forest System lands contribute to the nation's well being. Access to these commodities is dependent on public perceptions of the effects of mineral operations on other resources. An outlook is described which the Forest Service believes is essential to the minerals industry if it plans to continue seeking minerals on National Forest and Grasslands.

Jan 1, 1991

Production of oic at BHP Minerals Pty Ltd's Cannington Mine commenced in May 1997. The initial sloping blocks at the [nine are located in the upper part of the Footwall Lead lode, and the Hangingwall Lead and Glenholme Breccia lodes. This paper discusses the geological investigations, interpretation and modelling that was undertaken for the Footwall Lead lode production block at Cannington Mine, as well as providing a basic geological introduction to the Cannington deposit.

Jan 1, 1997

Henry D. Hibbard, High Bridge, N. J. (Communication to the Secretary): There is one chemical factor which has not been considered in the author's tabulation of tests, but which is none the . less important because it cannot be practically estimated, and that is the element oxygen. This element has been, and probably will continue for some time to be, one of the great causes of the continual discrepancies between the chemical and physical properties of steel. Probably oxygen occurs, in important proportions, only in soft steel, such as that which we are now considering. In this steel its physical effect is to diminish tensile strength and elongation. The percentage of oxygen in the steel, under working-conditions that are as uniform as possible, is likely to vary inversely as that of the manganese, or perhaps, and more probably, it may bear even an inverse geometrical ratio to the manganese-content. At all events, to follow the author's plan, the line representing the loss of strength due to oxygen is probably a curve. Plotted by itself, the line would probably be straight; that is, the decrease in strength would be proportional to the increase in oxygen, but if the results were superposed on the percentages of manganese, they would give a curve, because the percentages of oxygen increase faster than those of manganese decrease. Were the oxygen-line to be developed and added to the diagram, it would seem that the manganese-line should then be straight. Due allowance for the effect of oxygen, therefore, would modify two features of the paper. It would increase the figure for the strength of pure iron from 38,000 to about 45;000 pounds per square inch, and it would straighten out the manganese-curve. The manganese-line in the paper is curved between 0.50 and 0.20 per cent. Above 0.50 per cent. it is straight, which may be ascribed

Jan 1, 1893

Caterpillar recently held two, two-day demonstration programs for its mining customers. The event, billed as MineDemo by Caterpillar, consisted of two sessions held on consecutive weeks at the company's Tinaja Hills proving ground south of Tucson, AZ. The program included several classroom sessions that focused on Caterpillar equipment applications, including the VIMS (vital information management system) and the CAES (computer-aided earthmoving system). Also included were field demonstrations and the opportunity to test drive mining-related heavy equipment, including dozers, trucks, graders, shovels and loaders. Featured at the event were the recently upgraded 785, 789 and 793 C-Series trucks. Caterpillar recently announced the availability of the 136-t (150-st) 785C and the 177-t (195-st) 789C. The upgraded haulers have replaced the respective B-Series models. The 218-t (240-st) 793C was introduced in 1996. It, too, has been upgraded but retains the C-Series designation. While attending the press event, the author had the opportunity to test drive the 793C at the Tinaja Hills test site. It was amazing how well the machine handled. The operation was smooth and the braking system was precise. The cab was extremely comfortable. To see a C-Series truck in action, the author also visited Newmont Mining's Mesquite Mine, located in Cali¬fornia, across the border from Yuma, AZ. The Mesquite Mine operates a new model 785C truck. At the mine, temperatures have been measured as high as 58° C (138° F) in the pit. Needless to say, the ability to operate dependably in extreme heat is an important consideration for the mine operators. An interview with the driver and later with management confirmed that the 785C has worked out well. The driver praised the comfort of the cab and the ease of operation. Management reported significant fuel savings and was impressed by the truck's maintenance features.

Jan 1, 1999

By Yvon Trudeau, Deni Raymond

"The Orion gold mine, located 7 Ian northeast of the town of Malartic, Quebec, was discovered in mid-1985. Underground exploration was undertaken in 1986 leading to commercial production in 1988. The upper part of the orebody was exploited above the 125 m level and a total of 131 090 t at an average grade of 5.31 g/t gold were extracted.This paper describes the authors' current knowledge and interpretation of the geology, gold distribution, and structure of the Orion No.8 ore zone deposit. The deposit is an epigenetic lode gold occurrence somewhat unique in that both quartz-vein type and pyritic type of gold ore occur side-by-side. It is located within the Marban-Noriartic Deformation Corridor (MNDC) formed during a first deformation stage (D1) The MNDC is a well-defined regional structural feature in the Val d'Or - Malartic mining camp. Primary gold mineralization is associated with the D1 event and is represented by pyritized, silicified and brecciated basaltic lavas enclosed by ultramafic flow units. The ore zone is concordant with the MNDC. Felsic intrusions are spatially related with the ore zone, but their role in the genesis of the ore has yet to be dermed.A second deformation event (D2) resulted in local folding, a second schistosity (S2) and reverse faulting. Gold remobilization, the formation of the gold-bearing quartz breccia and the emplacement of the main quartz vein at the No. 8 zone deposit were associated with this event."

Jan 1, 1992

By Paul Bedard, Réal Daigneault, Guy Perrault

"La mine Lamaque est située a Val d'Or, Québec; les roches hônes appartiennent au groupe de Malartic, partie supérieure, et sont des andésites et des pyroclastites. On y retrouve deux formes d'intrusifs; des petites cheminées (ca. 150 m D) et des dykes (ca. 10 m d'epaisseur). Les petit es cheminées contiennent:1 - des diorites et des tonalites (cheminées principale, est et ouest) d'affinité calco-alcaline: Zr 140 ppm, Sr 761 ppm, P2O5 0.31% et (La/Sm)n 3.0;2 - des diorites (cheminée 4) d'affinités tholéiitique: Zr 32 ppm, Sr 181 ppm, P2O5 0.27% et (La/SM)n 1.5.La diorite de la cheminée no 5 contient deux fractions, une de chacune de ces deux affinités. Les dykes tant de porphyre feldspathique quartzifére que ceux de prophyre feldspathique sont d'affinité calco-alcaline: Zr 83 ppm, Sr 500 ppm et P2O5j 0.10%.Le gisement de 10 mine 2 est filonien: veines subhorizontales (""flats "") surtout et veines sub-verticales dans des zones de cisaillement. Le dernier réajustement structural de direction de compression nord-sud a broyé le quartz des veines existant es et rendu possible leur minéralisation. Les veines minéralisées contiennent du quartz, de la tourmaline, de la calcite avec des traces de scheelite, de pyrite et d'or; elles sont bordées par de minces (2 à 20 cm) bordures d'altération où l'on retrouve un enrichissement en carbonate, paragonite, apatite, rutile, saphène et zircon et où les phases ferromagnésiennes sont disparues. On a documenté le migrations géochimiques suivantes:I - de la bordure d'altération vers l'éponte, K2O, Rb et MgO;2 - de l'éponte vers la bordure d'altération, Na2O;3 - de l'éponte vers la veine, SiO2.P2O5, TiO2, Zr, Y, Nb et CaO sont enrichis dans la bordure d'altération."

Jan 1, 1983

The exploration industry generally has a low opinion of the quality of the service supplied to it by government departments. In particular, the academic research-related emphasis of the Bureau of Mineral Resources (BMR) and the relatively low level of explora- tion assistance offered by several Mines Departments are of concern. In a number of areas of geoscience research, the industry perceives a mixup of priorities and a lack of understanding on the part of governments as to its needs. While government's sights are, and should be, set on the future needs of the community at large, the industry doubts that government budget allocations to the BMR and Mines Departments are either large enough or being cost-effectively spent. This is certainly the case for such areas as exploration assist- ance, provision of basic exploration data, and applied geoscientific research. On balance, the exploration industry's perceptions are misguided in a number of respects because of a lack of communication with government. However, this reinforces the need for changes in the manner in which govern- ment departments communicate with industry and, in particular, the criteria upon which research priorities are based. At a time of contracting oil and mineral exploration expenditure, and near-record levels of geoscientist unemployment, the government's role is critical and should be open to question.

Jan 1, 1986

By H. L. Hinds

Economic pressures to increase production to profitable levels reduced the Homestake's gravity recovery and overall recovery to un-acceptable levels. The operation of the Home-stake gravity gold circuit has increased gravity gold recovery to over 50%, improved overall recovery and increased mill availability for increased tonnage. The gravity circuit consists of three gravity gold recovery stages. The Circuit has four (4) duplex jigs, four (4) belt concentrating strakes and four (4) concentrating tables.

Jan 1, 1989

Banks' focus in using cash flow methods can differ markedly from that of equity investors. This paper attempts to explain and describe bankers' approach by: ò outlining the fundamental difference between banks' and investors' risk / return profiles. ò describing lenders' consequent use of cash flow methods in mineral valuation. areas. explaining lenders' specific treatment of key risk Fundamental to understanding banks' appraisal of mineral projects is the appreciation that lenders have a basically different risk profile and outlook from those familiar to equity investors. Lenders do not normally participate in any project upside. The economics of lending dictate that banks can only accommodate a low probability of loan default and consequently banks' principal focus in mineral ""valuation"" is ensuring an acceptably comfortable probability of debt repayment. A simple conceptual explanation of lenders' risk / return position is outlined.

Jan 1, 1994

By Steven A. Savage

Agrico Chemical Company, as we presently know it, is the result of the coming together of several different fertilizer operations. The Williams Companies, our parent organization, first entered the fertilizer business in 1971, when it acquired the fertilizer operations of the Gulf Oil Company. This gave us, among other things, the manufacturing facility at Donaldsonville, Louisiana. In 1972, The Williams Companies acquired Agrico Chemical Company from Continental Oil Company, bringing in a manufacturing facility and phosphate mines at Pierce Florida. Our Florida Mines are in the region commonly known as the Bone Valley Region of Florida. The majority of the phosphate fertilizer produced in the United States utilizes rock mined in this region. The Donaldsonville Plant was originally built in 1967-68 on the site of the old Faustina Plantation at an approximate cost of $80,000,000. (This plant is commonly referred to as our Faustina Plant.) Until such time as Agrico was acquired from Continental Oil, the Donaldsonville Facility was solely used to upgrade phosphoric acid into finished granular products.

Jan 1, 1986

By Frank M. Howell

Creede, one of the younger major mining camps in Colorado, grew spectacularly to a town of eight or ten thousand people in the early 1890's following discovery of rich ore in the Amethyst and Last Chance mines. Gross metal production in gold, silver, lead, copper and zinc rose to a maximum of four million dollars a year in 1893. Annual production dropped to much lower figures and ranged between one hundred and five hundred thousand dollars per year during the period from 1914 to 1940. Production reached a gross of eight hundred thousand to one million dollars per year by the mid-1950's. In the years 1953 to 1957, Steven and Ratté conducted geologic investigations which were carried on as part of a cooperative program of the U. S. Geological Survey and the Colorado Metal Mining Fund Board. In a preliminary report on the Creede District, Steven and Ratté suggested that the Bulldog Mountain Fault Zone appeared to be a favorable structure to prospect. On the basis of that recommendation, augmented by independent work done by Manning W. Cox, the property was acquired, transferred to Bulldog Mountain, Inc. and financed by an O. M. E. loan. Late in 1963 Homestake Mining Company, under a Lease and Option Agreement, backed the venture by furnishing additional funds plus management.

Jan 1, 1969