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By Torres S. Ricardo, Encina M. Víctor, Segura O. Claudio

INTRODUCTION This paper is a conceptual resume of engineering studies that have been evaluated by the Mine Department related to production planning over the next twenty-five years. These studies have been required principally because: a) The Rio Blanco Mine, property of CODELCO- CHILE, Andina Division, faces an operational problem due to heavy snowfall in winter which enters the surface subsidence area of the cave; later melts and filters into the broken ore creating a product that is difficult to transfer through the orepasses. The phenomenon is especially serious during the spring and has been increasing over the years. This element that complicates extraction will be controlled with the procedures proposed or others that may be determined in the future. b) The mine will increase production in 1985 by 40% . LOCATION The deposit is located in the central region of the Andes Cordillera, at an altitude of approximately 3,600 m above sea level, 50 km to the northeast of Santiago. The main camp is Saladillo (at 1,300 meters above sea level) located 30 km from the mine. Due to its location, the mine is subject to heavy snow storms during the year. On many occasions the road from Saladillo to the mine is closed because of storms and avalanches. For this reason the company has self-sufficient civil facilities near the mine to cover the needs and welfare of the working force. These housing facilities are connected to the mine by underground passages. For the same weather related reason the primary and secondary crushers, and the entire concentrator complex are located underground. GEOLOGIC CHARACTERISTICS Geology Based on the geologic model developed for the Rio Blanco deposit and comparing it with standard models pertaining to copper porphyries, it can be concluded that this deposit is part of the apical sector of a mega deposit and therefore the projections of the Xio Blanco cop per mine are very favorable, both in lateral area and depth. In order to confirm and evaluate these geo- logic features, an extensive drilling program was started at the Rio Blanco deposit. Diamond drill holes were drilled to depth as well as in the areas named "La Americana", "Don Luis" and "Elguin". The area explored by the drill program is 3 km long in a north-south direction and 1.5 km wide in an east-west direction. In some sections the drilling in depth reached the 2,300 m elevation mark. The lowermost level in the mine is at elevation 3,070 m. These new studies have permitted the recognition of the following lithologic units: Andesite Andesite Breccia Granodiorites, Rio Blanco and Cascada Granodiorite Breccia Quartzmonzonite Porphyry Monzodiorites and Latites Tourmaline Breccia Dacite Pipe and Rhyolite marginal ring. The mineralogical study permits the definition of three stages of hypogene and hydroterma1 alteration of importance with a time-altered sequence. These stages correspond to a late hydrothermal stage. The kinds of alteration that have been recognized are: Potasic Alteration Propylitic Alteration

Jan 1, 1981

FINAL REPORT OF' THE COMMITTEE OF THE AMERICAN INSTITUTE OF MINING AND METALLURGICAL ENGINEERS W. E. FOHL, Chairman J. W. PAUL J. M. RAYBURN C. A. WARNER JOHN B. CORRIN C. E. KREBS JOHN H. WILSON A. W. HESSE M. M. LEIGHTON H. I. SMITH [Accepted and Committee discharged with thanks, April 27, 1928.] Regulations recommended for the location, drilling, casing, protection, operation, plugging and filling, and abandonment of natural gas and petroleum wells; having for their objectives the protection of life and property by prevention of intrusions of oil and gas into workable coal beds, and the conservation of oil and gas resources in territory not underlain with workable coal beds. ARTICLE I DEFINITIONS SEC. 1. For the purpose of these regulations, definitions are as follows: Well.-A bore hole drilled for the purpose of developing natural gas or petroleum, or a bore hole producing natural gas or petroleum. Well Operator.-Any person, persons, firm, partnership, corporation, company or association that proposes to, or does drill, operate or abandon a well as herein defined. Coal Operator.-Any person, persons, firm, partnership, corporation, company or association that proposes to, or does operate a coal mine in territory known or reputed to be underlain with oil or gas-bearing strata. Coal Owner.-Any person, persons, firm, partnership, corporation, company or association, other than a Coal Operator as herein defined, that owns coal lands in territory known or reputed to be underlain with oil or gas-bearing strata. State Mining Department.-The duly constituted authorities of a state having jurisdiction over coal-mining operations, and oil and gas operations as herein provided. Plat.-A map, drawing or print made in accordance with the provisions of these regulations. Casing.-The pipe commonly used in wells drilled for natural gas and petroleum. Oil and Gas.-Synonyms, respectively, for Petroleum and Natural Gas.

Jan 1, 1928

By Howard Eavenson

The data given in the paper were collected to furnish an idea of the amount required in various operations of bituminous mining to produce a ton of coal, the plants selected being well-managed ones. With these are included some figures compiled from U. S. Coal Commission's report showing the average amount of labor in various classes of mines. THE information contained in the following paper was collected at the request of the U. S. Coal Commission, and is, published with the permission of that body and of the various companies furnishing the data. For obvious reasons, the names of the companies are not given. No data were gotten from States south of Virginia or west of the Mississippi River. The data about the amount of labor, in man-hours, required in producing a ton of bituminous coal have been collected with the idea of showing what is being done at some well-managed plants, and not to show the average amount required by all mines, which undoubtedly is considerably higher than the average of the figures shown.* Almost all of the figures were supplied by the various companies in reply to a questionnaire; when they were obtained from other sources the company was asked to verify them. On account of the amount of work required, the data were only requested for one or two months for each plant, and the figures represent in each case a month when the car supply was good and the work was practically steady. In the case of most of the West Virginia and Kentucky mines, these conditions were best met in May and June, 1922. The mines for which the figures are given are arranged by states and as to whether the mine operates under union or non-union or open-shop conditions. The union mines listed are generally considered to be as well-managed as are the non-union ones. The production per month in a few cases includes the amount of slate which is loaded and hauled out of the mine, as of course this requires nearly as much labor per ton as does the coal. These cases are noted:

Jan 1, 1924

By Dan Chun

Abstract-To facilitate the efficient handling of large volumes of information generated by logging exploration drill cores, a computer data bank system (GEOBANK) has been developed to store and retrieve the normally difficult to handle geologic information as well as the physical testing data. The data bank systematized the logging of drill core by first developing a standard list of adjectives or descriptors (with the corresponding assigned numerical codes) for the various stratigraphic categories that are also assigned numerical codes. The system uses the "floating-slot" concept and handles the data bank with one single input form.

Jan 9, 1978

By Alfred Weiss

When I first received the announcement of this meeting I was pleased to see that this 14th APCOM Symposium had expanded its range of interest. One new topic to be considered this year is long range or strategic planning--the continuous process by which current risk taking decisions are made systematically, and with the greatest knowledge of future impact. Long range planning should receive our attention. It is the first step in the management process and the foundation of many--if not all --key managerial decisions. Improvements made at this stage of managing are almost certain to be of benefit in later stages of decision making. It is obvious to many of us that in a physical process such as mineral beneficiation, one does not concentrate all of one's attention on the flotation design without also considering the grinding, cycloning, and desliming stages of the process. Taking this a step further it would be equally erroneous to find a mineral engineer designing a mill without due consideration for mine, smelter and refinery and beyond that the sales goals, growth and profit objectives of the firm itself. And yet, how many times have we seen organizations staff and reorganize without consideration of an overall plan; without adherence to the management process which by its definition, calls for a plan first, followed by the appropriate organization and staff. The computer applications traditionally discussed at APCOM meetings have concentrated on areas dealing with things and people-- the implementation of the plan, rather than with concepts and ideas, the formulation of the plan.

Jan 1, 1977

By Richard P. Sheldon

In the last several decades, techniques of data collection have been rapidly evolving. Automated spectroscopic techniques in the chemical analysis of rocks for example have advanced to the point that we can analyze samples faster than we can grind them. Remote sensors of LANDSAT give us intensity measurements in four color bands of every acre of the U.S. every 19 days. Common depth point seismic instrumentation systems used at sea for surveying and networks of seismometers arrayed around the country for earthquake studies likewise are generating vast amounts of data. These along with many other earth science data generating systems have caused a veritable data explosion. How do we deal with these enormous amounts of geologic data presently being produced as well as those produced in the past, and to be produced in the future? There is an immediate need to acquire and utilize past and present basic data in order to address today's national earth science problems. Also data being collected and stored now must be compatible with future data in order for us to be able to undertake the wide spectrum of analysis that must be made in the future. This is a big order! In order to organize and to be able to analyze these data, the USGS has embarked on a wide ranging program of compatible data base construction and the development of computer technology, based on interactive computing, to facilitate resource assessments and analyses. These activities are analogous to two sides of a coin. One side deals with the logic, philosophy, and mechanics of information storage and retrieval; and the other side deals with the sensible application of computer technology to the treatment of data. These

Jan 1, 1977

Jan 1, 1915

By A. N. Diehl

IT is the object of this paper (1) to deal with the elements in blast-furnace gas from the standpoint of their importance, and the part they are to play in future consumption, and (2) to give detailed information about the construction and operation of a plant designed among the first in this country for washing gas on a large scale.

Jan 5, 1914

By Richard F. Link, George S. Koch

About 50,000 assays of mine samples were required in a preliminary investigation of the distribution of gold, silver, lead, copper, and zinc in two large Mexican mines, the Frisco mine at San Francisco del Oro (Chihuahua) and the Fresnillo mine at Fresnillo (Zacatecas). The feasibility of working with so many assays rests directly on the use of machine processing methods. The purpose of this article is to describe the methods used because machine (or data) processing can also be used efficiently to make the many calculations from mine assays needed in mining operations. No particular originality is claimed for these methods, which are straightforward applications of standard procedures for machine processing. Inasmuch as machine processing is essentially a routine job once it is begun, procedures must be organized more completely than is the case where human judgment can be inserted at every step. Before undertaking any work, it is necessary to decide carefully just which data must be processed as well as the exact results desired.

Jan 9, 1960

By Gerald V. Jergensen

Does an idea have merit? What does it cost to implement? Can the concept be implemented successfully? The ultimate proof is to try, then see. However, when there are many millions of dollars at stake, blindly building and trying requires considerable courage. Owners and investors in retrospect might choose other less complimentary words. So we might ask, "How might we establish the feasibility of an idea or concept before committing large sums of money to the ultimate test?" From this basic and prudent question, has evolved the engineering concept of the feasibility study. A feasibility study is simply a systematic evaluation of an idea or concept to determine the prospects for success. In a literal sense, a feasibility study considers an idea in terms of its data base, "builds" the idea on paper, "operates" that idea, calculates the cost and benefits, then measures the probable success in terms of some economic, technical or financial standard. Feasibility studies can be quite modest in scope yet provide useful insights as to the viability of an idea. A study might be initiated only to examine the completeness or validity of the metallurgical data base. Another study could be a search for a workable idea or solution to an already-identified possibly troublesome problem. In this latter case, the question, "Will it work?" may be far more important than, "How much will it cost?" Feasibility studies are sometimes global in scope, involving several dozens of specialists and examining an entire "grass roots" mining complex. Other studies may be less ambitious but equally important in examining an expansion proposal or developing new operating techniques. Studies may be commissioned to remove plant bottle-necks, solve maintenance problems and so on. The terms study and feasibility study are used interchangeably in this chapter. They denote a systematic method to examine a proposed concept or idea. DATA BASE Typically, studies are initiated with a minimum amount of specific information and a maximum number of assumptions. As the work proceeds and the data base expands, assumptions are replaced

Jan 1, 1982

When the writer first began his search for the early history of coal he was amazed at the paucity of information in literature about it, and while after six years many of the reasons for such a scarcity are understood, there are still many cases, even within the last two centuries, when one who can appreciate the tremendous part coal has played in the development of modern times, finds it hard to realize how little attention was paid to this material in those early clays. Occasionally a traveller or observer is found who foresaw how valuable coal was to be when industries were developed, but these were few and to most of those recording its occurrence it was just another mineral. George Washington was farsighted in his view of the development of this country and the need for means of transportation across the mountain barrier, but it was at least sixteen years after he must first have known of coal before he made any reference to it in his journals. He did, however, knowingly or not, select some valuable coal properties in the lands lie obtained in the West. This was then almost entirely an agricultural country, and what industries there were found a great abundance of wood fuel within easy access, there were no steam plants, and all iron was made with charcoal; in fact, the "captive mines" of the iron industry then were large timber "plantations," and when these were exhausted the furnace usually was abandoned and another one built elsewhere, as transportation of charcoal was quite expensive. Along the seaboard the cities and industries began to import coal from England and Nova Scotia early in the eighteenth century, but until the war of the Revolution began the total quantity of coal used yearly in this continent did not exceed nine thousand tons. In 1800 only two places, Pittsburgh and Richmond, Virginia, were using coal to any extent for domestic purposes and it was much later. than this that the amount of coal used in Philadelphia, New fork, and Boston exceeded that of wood. Practically all of the early travellers and writers mentioning coal are noted in the following pages. Several Englishmen who were evidently familiar with its use and value at home, mention its presence as being of great future promise to the young nation, but to nearly all it was more or less of a curiosity and the smoke caused by its use an abomination, and it

Jan 1, 1942

By Fred M. Phillips

Jan 1, 1985

Carlisle: This is April 19, 1961. My good friend Dave Irwin is sitting on the other side of the tape recorder. We are at Rose Dhu Island, Savannah, Ga. Now, let's begin with your first job, where and what was that? Irwin: I started out to Arizona, looking for a job and wound up in Morenci. The next morning I applied at the mine office and was put on as a sampler. I worked as a sampler and as an assistant to Frank Pelton, the geologist, for a year, after which I went back to New Haven to take my last year of postgraduate work. After getting my degree, I went back to the Southwest with W. Rowland Cox and Staff, supposedly as a geologist. Q: But that was not when he was with Spurr? Irwin: That was after he had left Spurr. Henry Smith was with the Spurr end of the outfit and I happened to drop into the W. Rowland Cox end. My first job with him was to do some work on a prospect above Metcalf, Ariz., and from there I would go out on short reconnaissance trips in Arizona, New Mexico and old Mexico.

Jan 6, 1964

By AIME

A NATIVE son of Salt Lake City. David Douglas Moffat has contributed greatly to both the mineral industries and civic progress in the State of Utah. He was born in 1880 and his whole life bas been intimately associated with mining and milling. His father, one of Utah's pioneer mining men, was superintendent of a mill at Park City. When Moffat was only 18 years of age he went to Philipsburg Mont., where he spent several years as a machinist, and later as master mechanic for the Granite Bi-Metallic Mining Co. He returned to Park City in 1903 as master mechanic and night mill foreman for the Ontario Silver Mining Co. After a few years of varied experience he became, in 1910. general foreman of the Boston Consolidated Will at Garfield, Utah.

Jan 1, 1947

By J. E. Johnson

THE production of metal-working tools has been revolutionized within the last 18 years, since the invention by Taylor and White of a process of heat-treating steel tools, which resulted in increasing their cutting capacity several fold over what it had been before. This was an exceedingly important invention, although it consisted principally, in establishing this fact overheating when it accidentally, occurred in the ordinary:-process of forging, spoiled the steel, but if carried very much farther or to-a point that would have been considered absolutely ruinous to the steel under the old ideas, it resulted in imparting a cutting power several times as: high as had ever been obtainable before. The quality that gives the steel this power eventually received the name of "red hardness." This name originated in the fact that tools possessing this property retain their resistance to deformation even when subjected to, such severe cutting stresses that the metal just back of the point is heated, under certain conditions, to a visible red. It is interesting in this connection to note that the edge of the tool itself does not become red because it is continually cooled by the fresh metal into which it is forced. The result of Taylor and White's invention was an intensive study, of tool steels all over the world and, although there was-great diversity of analysis in the high-speed steels of the early days, these steels today generally have an approximately similar composition, the principal constituents being froth 15 to 20 per cent. of tungsten, from 4 to 6 percent. of chromium, from 1 to 2 per cent. of vanadium, and from 0.50 to 1 per cent. of carbon. It is probably safe to say that standard brands of such high-speed steels will do from five to ten times as much work in a given time as the carbon steels, and even the Musket steels, which were the sole dependence up to the beginning of this century, when the Taylor-White process was discovered. With the increasing cost of labor, it is not surprising that these steels have driven froth the market, for all but limited purposes, the older types of steel.

Jan 2, 1919

J. A. Mathews,* Syracuse, N. Y. (written discussion?).-It is interesting to note how frequently we hear of some process that is going to revolutionize the tool-steel business. I don't know why it is, but every one seems to have it in for us poor tool-steel men. About 15 years ago, a good-sized plant was built in Syracuse for the manufacture of cast tools of malleable iron. The promoter of the scheme claimed to have a secret, process that had been given to him by a tramp to whom he gave a lift along a dusty road. The widows and orphans invested liberally in the securities of the company without consulting the men established in the machine-tool business in Syracuse. About two years later, when the sheriff's sale occurred, the secret, which was carried on the books of the company as an asset valued at $2,000,000, brought $15 at auction. A little later another concern started on the theory of replacing scrap high-speed steel with new high-speed steel tools made therefrom. All the tool-steel companies have made a practice of purchasing high-speed

Jan 5, 1919

By James L. Poole

INTRODUCTION Companies in the mining industry are subjected at times to currency exchange rate risks and interest rate risks. The former occurs any time a firm deals in more than one currency. The latter occurs anytime a firm is financing itself with borrowings that have a floating interest rate (although a fixed rate can be a problem at times). FOREIGN EXCHANGE RISKS There are two general reasons why exchange rate risks (FX risk) can occur: First, a firm may be building a mine or plant in another country where financing for the plan is denominated in funds other than the country hosting the plant. For example, if a Canadian firm is building a smelter in another country which is being financed with Canadian dollars, the C$100 million for labor, which must be paid in the local currency, has subjected the firm to a C$100 million FX exposure risk. If after the cost estimates were made the local currency appreciates 30% against the Canadian dollar, the cost of labor has increased to C$130 million. (Of course, the local currency could also devalue during this period making the labor cost component less than estimated.) The other reason exchange rate risk arises is due to the fact that the costs of production in one country producing minerals may be incurred in one currency while the production is sold in another currency, such as coal being exported from Canada to Japan under contracts denominated in Yen. In this example, the Canadian firm is exporting coal to Japan and being paid in yen in 30 days at a contract price of 100 Y per ton. Furthermore, assume that the mining firm anticipates a depreciation of the yen against the Canadian dollar of 5% in the next 30 days. Therefore, the mining firm stands to lose 5% of the value of its shipment in a month's time not including carrying costs. In both cases, the mining company risks an adverse change in the exchange rate, that is, the currency the company holds may decrease in value relative to the other currency. There are a number of ways to mitigate the exposure to foreign exchange which can be utilized by the mining company. Optimally, a company should try to match all their inflows and all their outflows in the same currency. For example, if a Canadian firm has mining costs and debt service costs both denominated in Canadian dollars then 100% of their receipts would need to be in Canadian dollars. If a Canadian firm has 70% of its cash outflows in Canadian dollars and 30% of its cash outflow in American dollars in the form of a loan amortization then their receipts would need to be 70% in Canadian dollars and 30% in U.S. dollars. This general principle of matching cash receipts and cash costs in the same currency works fine in a perfect world but what of the real world when these cannot be matched? In actual practice, however, the financial markets have developed a number of ways in which foreign exchange risks can he managed or reduced. FORWARD MARKETS One method is to use the forward markets which are made on a world-wide basis by the commerical banks for foreign exchange. If a firm wanted to lock in the current exchange rate for the receipt of a foreign currency at some point in the future, they could do so by contracting on the forward market with a bank selling that foreign currency at the current rate at the future date. For example, assume that a Canadian firm is exporting coal to Japan which would pay yen in 90 days. If a firm wanted to lock in today's exchange rate they could contract with a bank to sell on the forward market yen in 90 days. When the yen was received the contract would be executed by selling the yen to the bank and receiving the previously agreed upon number of Canadian dollars. Generally speaking, the forward market can be used to sell forward about 12 months. The costs of selling (or buying) forward

Jan 1, 1985

By AIME AIME

MORTIMER ELWYN COOLEY, dean of the College of Engineering and Architecture of the University of Michigan, has been elected president of the American Engineering Council of the Federated American Engineering Societies. This was announced at a meeting of the Executive Board of the Council held at the Cosmos Club in Washington on Sept. 30. Dean Cooley assumes office at once. The new head of organized engineering is a past president of the American Society of Mechanical Engineers and has a long record of distinguished service in education, under the government and in private capacities. He was born in Canandaigua, N. Y., March 28, 1855, and was graduated from the United States Naval Academy in 1878. With his classmate, Dr. Ira N. Hollis, he was ordered to the U.S.S. "Quinnebaug," then fitting out at the Norfolk Navy Yard preparatory to a cruise in the Mediterranean.

Jan 1, 1921

By Elmer A. Holbrook

You moderns think of your field of work as "Minerals Beneficiation"; to me it always will be "Ore Dressing." While I would like to talk with you on the future of ore dressing rather than the past, I cannot do this because I started to work in the field some 56 years ago, and my future is behind me. It is trite to remind you that then, in 1900, one out of every 30 high school graduates went on to higher education. Today, the figure is one in every three. So that, while you have a lot more men to compete with, the field of opportunity has expanded even more.

Apr 1, 1956

By Anna H. Connard

SUMMARY The discussion focusses on developments in the debt/equity swap market since the Marte project was negotiated in early 1988. It emphasises carrying forward the recent market trends to anticipate the breadth and scope of debt/equity conversions for mine development in the 1990s. Secondary market prices of LDC paper, conversion values and political influences in the host countries and the use of near debt and commodity-based instruments as components of mine financing in debt/equity deals will be placed in the perspective of recent trends and expectations for the future. THE MARTE PROJECT The Marte mine is a gold porphyry deposit in Chile's high Atacama, for which financing was put together at the beginning of 1988. The Marte project was financed by a combination of common equity and loans. It was unusual that the equity infusions were made under different programs. Some of the international equity was infused with fresh funds via DL 600. Other common foreign equity was provided through the conversion of Chilean bank debt under Chapter XIX. On the loan side,. export credits for the import component of machinery and equipment were sought. Local bank financing was negotiated for the remainder of ' the project's anticipated cost. The debt conversion market in Chile was at its apex in terms of interest, activity and government support when the mine financing was arranged. The price of Chilean paper in the secondary market hovered about 62 to 66 cents per U.S. dollar of face value. Meanwhile, the Chilean government was negotiating conversion redemptions significantly closer to full face value. The government differentiated between debt paper exchanged for corporate investors who had sourced that paper in the secondary market, and debt paper held by bank investors who would incur a transaction loss in the conversion. The use of a combined DL 600lChapter XIX equity financing created different yield calculation bases for the various investors. Chapter XIX prevents remittance of profits before year 5 and capital repatriation before year 11. Investors choosing this vehicle have either for a corporate policy in the target project not to declare dividends until repatriation is allowed, or they have to seek uses for the peso liquidity that would be generated through dividend declarations in the early years. However, DL 600 investors face no such waiting period on dividends, nor do they have restrictions imposed on cashing out of the investment before the 11th year. Therefore, any equity structure with components of both investment mechanisms will have inherent differences in cost basis and future income flows for the various participants. This equity imbalance is defensible if the investment motivations of the parties are analyzed: a mining investor using fresh funds looks for a hurdle return on equity calculated at conservative commodity prices, with as much flexibility to reap upside benefits as possible; a mining investor choosing to invest through a debt conversion mechanism will realize a modest short term gain on the conversion, reducing his effective cost basis, but sacrificing some return because of the waiting period on repatriation of dividends. INVESTMENT OBJECTIVES A bank investor exchanging his own paper for an equity participation in a mining project realizes a conversion loss on the transaction. He seeks a risk adjusted acceptable hurdle rate of return to recoup that loss over time. Motivation for the bank investor to take that loss may be derived partly from a strategy to diversify its existing portfolio by internal policy and externally regulated guidelines. The bank will compare yields on its loan portfolio to that country with anticipated dividend flows discounted back at a risk adjusted rate. It will analyze the project with return objectives of yield enhancement over time and with

Jan 1, 1990