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By I. H. Keith

INTRODUCTION The following papers describe the extraction of nickel in the form of ferronickel from the Dominican laterites. The Falconbridge process was developed initially in the Falconbridge Metallurgical Laboratories and subsequently in several successive stages of pilot plant operation in the Dominican Republic. In the course of this work we came to believe that there is advantage in piloting on site. Mining, metallurgical and geo-political considerations all have major impact and that belief has been borne out by commercial plant experience. Lateritic nickel ores differ substantially, even within the same orebody, in their amenability to extraction methods. The Falconbridge process takes account of the heterogeneous nature of the deposit. Three years of geological field exploration led to ten years of process development after it was realised that the then known metallurgical processes would not give economical extraction from the Dominican ores. In addition to establishing the viability of a novel pyrometallurgical approach, it was necessary to verify design parameters for a very considerable scale-up to prototype commercial operation. The plant was eventually constructed within the original estimates of time and cost. Unique features contributing to the technical and commercial success of the project are described. Additionally, some bold extrapolation based on pilot plant work, eventually proved to be quite conservative. The mine is not a conventional open pit operation, but is perhaps better characterised as an earth moving job. Novel application of mobile equipment led to great flexibility in the mine, where operation of several mining fronts is essential to maintaining uniformity of ore feed to the plant. The practical aspects of almost total acceptance of the oversize run-of-mine material through a high-capacity unit,

Jan 1, 1979

By R. B. Sosman

INTRODUCTION IT is well known that ferric. oxide, Fe.-,03, is paramagnetic, while magnetite, Fe304, is classed among the highly ferromagnetic substances. But magnetic data on oxides intermediate in composition between Fe-03 and Fe304 have been almost completely lacking. Fe203 and Fe304 form a solid-solution series, according to present evidence.' In this series the properties change continuously from Fe203 toward Fe304, as the percentage of FeO increases from zero toward 31.03, which is the percentage in magnetite. It is possible that there is a break in the series near Fe304, but it has not yet been possible to establish the existence-of such a break experimentally. The occurrence of solid solution ill this series is shown by the dissociation pressure, or oxygen pressure in equilibrium with the oxides, which falls continuously over the range from Fe203 to Fe304. The oxygen-pressure curves at 1,100° and 1,200° are shown in Fig. 1. The existence of solid solution is also demonstrated by the continuous change in optical properties from Fe203 over to a composition containing about 18 per cent. FeO, at which point the opacity of the oxide becomes so great that it is im-possible to obtain measurements at higher percentages of ferrous iron. Natural oxides of iron intermediate in composition between Fe2O3 and Fe304 are much more common than is generally supposed. If a mineral oxide is not strongly attracted by a small hand magnet and if it gives a red streak, it is usually labeled "hematite." If it is strongly attracted by the hand magnet it is usually labeled "magnetite" without further tests. As we shall show later, oxides containing from 1 up to 31 per cent. FeO can be thus erroneously lumped together as "magnetite." It is a fact, nevertheless, that the great hulk of natural oxides of iron lie fairly near either Fe203 Or Fe304 in composition. The reason will be

Jan 6, 1917

"Every year during the Transportation Research Board (TRB) Annual Meeting in Washington D.C., the Federal Highway Administration (FHWA) National Geotechnical Team (NGT) takes time to talk about what we are doing in research, training development and policy support. At times, I have jokingly referred to it as the State of the Program Address, but we do see it as an important opportunity to update our transportation partners on priorities and needs for the program.This update is really a snapshot of the program during the previous year, with a look at projects that are currently active. Activities undertaken by the NGT are funded from multiyear roadmaps maintained by the FHWA program and research offices, and reflect trends and opportunities affecting and influencing transportation geotechnics now and in the future. The roadmaps identify activities in research, development, guidance, technology transfer and training that will be accomplished by the NGT through and beyond FY 2020 in eight broadly-defined focus areas: • Extreme events, geohazards and sustainable geotechnics• Performance management• Reliability-based design and construction• Advanced geotechnical modeling• Alternative delivery methods• Design and construction optimization• Site characterization• Quality assuranceThe process to identify focus areas and to develop activities that will be addressed by the NGT is guided and informed through input from the FHWA NGT members, and considers feedback and input from State Departments of Transportation (DOTs), FHWA Division offices, industry and academia. This process is revisited annually to review not only the activities that are currently funded, or will be funded, but also to review the relevance of the focus areas with respect to the future needs of the FHWA, State DOTs and the transportation community.In 2016, the NGT was successful in delivering several products that will advance the state of the practice and that better support policy. Products developed included research reports, design and construction guidance, and training courses. In 2017, the research and program offices will continue to work on projects that fit within our prioritized plan and that positively impact the geotechnical community as a whole. A listing of recently completed and currently active projects is provided below."

Jan 1, 2017

By Rob Farnfield, Charlie Adhock

The measurement of near-field shock has always been an attractive proposition for those working in the field of explosive and blast performance. The most commonly employed technique involves the use of piezoelectric accelerometers. Although highly effective, these complicated devices are relatively expensive and are often destroyed in the blast event. This paper describes the development and field-testing of a shock sensor of sufficiently low cost to enable it to be routinely used in product blasting. This new device is based on piezoelectric wafer technology and does not require any external signal conditioning. The device is housed in a small cylindrical package with approximate dimensions of 30mm (1.2”) length and 5mm (0.2”) diameter. It has been determined that the most effective way of fixing the device to rock is in a small diameter hole with epoxy glue. Alternatively the sensor can be simply placed in holes filled with either water or bulk emulsion explosive.

Jan 1, 2005

By Cameron A

In recent years there have been significant developments in the tech- nology available for blast monitoring, analysis and simulation. Progress in these areas has been achieved through research conducted by explo- sives manufacturers and independent research groups from universities and mining companies. Miners are increasingly keen to exploit this tech- nology to help them design blasts which make optimum use of explo- sives to produce easily excavated muckpiles for the minimum possible cost. The art of blast design in the future will increasingly depend on an adequate understanding of the nature of the rock mass, the perfor- mance of explosives and the characteristics required of the muckpile to suit the chosen excavation machinery. Despite recent advances in blast simulation and the prediction of blasting performance, the best way to determine how a particular explosive will function relative to other explosives is to conduct properly designed and monitored field trials. This paper discusses recent work at Mount Thorley Colliery which demonstrates that field blasting trials can be monitored and analysed to provide quantitative data on the relative performance of bulk explosives. Techniques used in the trials included the sampling and analysis of explo- sives, insitu measurement of VOD, monitoring of near and far field vibra- tions, high speed and still photography and survey measurement of muckpiles. These techniques provided data for the analysis of throw, swell, fragmentation and burden movement together with data on the consistency and robustness of different explosive products. The blasting trials allowed both the shock and heave energy of various explosives to be observed in the field and led to the derivation of design rules for the use of differ- ent explosives at the mine.

Jan 1, 1988

By Peter Joralemon

I want to limit my remarks to epigenetic ore deposits, but do not necessarily subscribe to the classic theories of hydrothermal ore deposition. I will consider an epigenetic deposit as a primary deposit in which the economic minerals have been introduced subsequent to the formation of the enclosing rock, regardless of the source. Past ore discoveries have been made to a great extent by prospecting techniques that have remained relatively constant over the last many decades. In many cases the discoveries have been enlarged or enhanced with the use of technical tools such as geophysics, but theoretical geology, which should serve as a foundation for exploration, has shown little progress of practical importance since the turn of the century.

Jan 1, 1967

The fifth convention of the National Foreign Trade Council was held in Cincinnati, Apr. 18, 19 and 20. More than one thousand accepted delegates were registered, the American Institute of Mining Engineers being represented by W. L. Saunders and W. N. Thayer. The convention was called to order Thursday morning, Apr. 18, in the convention hall of the Hotel Gibson; by the Chairman, Mr. James .A. Farrel, president of the U. S. Steel Corporation, and was in continuous session for two clays, several group sessions being held simultaneously. The convention adjourned Saturday morning after receiving the report of the central committee. The dominant themes of the convention were: First, "Win the War" and second, "Establish Foreign Trade on a. Firmer Basis." The discussions included textiles, lumber, chemicals, automobiles, finance, and agriculture, and also those things in which mining engineers are particularly interested, metals, oil, and coal. The report of the central committee, which was adopted, recommended the stimulation' of production of all materials required for war purposes; the subordination of all trade that will not impose new and heavy penalties on our adversaries; the maintenance of such foreign trade as will support national credit and supply materials required for military and naval purposes; the continued interchange so far as possible of merchandise and products between the United States and. Latin-America, Asia and Oceania; the immediate increase of tonnage in the north Atlantic; the cheerful and whole-hearted cooperation of importers

Jan 6, 1918

By Bodnaras G. E, Sceresini P. A

The Filblast Cyanidation Process incorporates the advantages of intense high shear mixing, high dissolved oxygen concentration and high pressure to achieve extremely rapid gold dissolution rates. This is made possible by the unique design of the Filblast gas shear reactor. The reactor is a rugged and compact in-line device. The outer casing is protected by a polyurethane coating and the internal parts are of wear resistant polymer. The largest unit built to-date has overall dimensions of 1200 mm length by 300 mm diameter and has a capacity of 150 dry tonnes per hour at 40 - 45 per cent solids. Service life at this throughput is at least three months. The process may further be applied to high temperature leaching of refractory gold ores or other metals. Wear resistant metal or ceramic materials would be employed for this duty. Four mines are currently employing the Filblast Process for treating a variety of ore types ranging from highly reactive, almost impossible to treat, pyrrhotite/arsenopyrite to deeply weathered clay ore which forms a highly viscous pulp. The effect of shear thinning has resulted in improved adsorption kinetics resulting in higher carbon loading and reduced soluble gold loss. Total tonnage treated is approximately four million. Operating costs which include leasing and maintenance charges for the Filblast and pump power costs are about 16 cents per tonne. This is equivalent to about ten per cent of savings. Laboratory scale units having capacities up to 30 litres/min are available for test work but laboratory testing techniques so far developed do not accurately reflect the oxygen and cyanide savings which have been achieved in the plant.

Jan 1, 1994

By B. J. S. Sceresini

The Filblast Cyanidation Process incorporates the advantages of intense high shear mixing, high dissolved oxygen concentra­tion and high pressure to achieve extremely rapid gold dissolu­tion rates. This is made possible without suffering from high energy or wear rates by the unique design of the Filblast gas shear reactor. The reactor is a rugged and compact in-line device which can be constructed from a variety of wear and chemical resistant materials. High temperature tolerance is also possible so that the device can be incorporated into a pressure leach circuit with significant capital cost savings because of the high capacity to volume ratio that is an inherent feature of the device. For cyanidation applications the outer casing is protected by a polyurethane coating and the internal parts are of wear resistant polymer. The largest unit built to date has overall dimensions of 1200 mm length by 300 mm diameter and has a capacity of about 150 dry tonnes per hour at 40-45 % solids. Service life at this throughput is at least three months. Six mines are currently employing the Filblast Process and another six are conducting plant trials. The ore types range from highly reactive, almost impossible to treat, pyrrhotite/ arsenopy­rite to deeply weathered clay ore which forms a highly viscous pulp. It has been found that the effect of shear thinning has resulted in improved leaching and adsorption kinetics resulting in higher carbon loading and reduced soluble gold loss. Total tonnage treated is approximately eight million tonnes per annum. This paper presents the operating benefits and cost savings which have been achieved in four plants, two treating oxide/ sulphide ore blends and two treating highly reactive sulphide ore and concentrate. Filblast leasing and maintenance charges and pump operating costs are about ten percent of the benefits. A conceptual cyanidation circuit based on the Filblast Cyanidation Process is also discussed. The Filblast System is an in-line pressure leach aerator/ reactor which generates very high shear and greatly enhances mass transfer rate by generating extremely small gas particles where oxygen gas is required for oxidation reactions and/or utilising the high shear characteristics to minimise the diffusion boundary layer. Both of these rate limiting factors effect the rate mechanism for gold cyanidation. Initially two multi-stage Filblast aerator cartridges formed a leach train but now the trend is to install a single submersible cartridge of equivalent perfor­mance. This design simplifies installation and minimises change-out times. However the in-line concept can be employed where high pressure leaching or pressure oxidation is required. The reactor is submerged in the leach tank so that the mass of gas micro-bubbles contained in the discharging slurry is entrained in the agitator vortex and is thoroughly dispersed throughout the tank. A diagrammatic representation of a leaching circuit incorpo­rating the Filblast Reactor is shown in Figure 1. The recirculation pump takes new feed directly from the cyclone overflow trash screen either under gravity or pump fed and recirculates the balance to maintain 250 - 270 m3/h total slurry flow. All of the leach feed slurry gets at least one pass through the Filblast thereby eliminating short-circuiting. Typically a 6/4 EAH Warman pump drawing 60-70 kW is required to circulate 250 m3/h through the system. The back pressure generated by the Filblast is in the range of 400-500 kPa depending upon pumping rate, pulp density and slurry rheology. The high shearing rate effectively negates the viscous effect of slurries and the addition of a gas further reduces the pulp density by virtue of the intensely aerated, homogeneous medium. The gold leaching Filblast cartridge elements are made of polyurethane but stainless steel, ni-hard, rubber or ceramics can be used depending on the operating temperature and design duty. The efficiency of the Filblast Leach Reactor in gold cyani­dation is due to the extremely efficient mixing, oxygen dissolu­tion and surface polishing action of the Filblast design. Either air or oxygen may be used but Atomaer recommend the use of oxygen because of the rate benefits gained from cyaniding at [02] significantly > 20 ppm D O in the reactor. Very high DO concentrations have been measured; in excess of 50 ppm. There is some debate as to whether the value is a true measure of the DO or the oxygen meter sensor is measuring the effect of a mass of very fine bubbles of free oxygen. Regardless of the fact the reactor has registered some amazing gold dissolution rates commonly in excess of 80 % during transit of the pulp through the reactor. The elapsed time is less than half a second!

Jan 1, 1995

The Filblast Cyanidation Process incorporating intense high shear mixing, high gas mass transfer efficiency and high oxygen concentrations under conditions of elevated pressure has now been been successfully applied in gold cyanidation mills since May 1993. The first commercial unit had a slurry capacity of 110 cubic metres per hour. Since then 230 and 450 cubic metre per hour units have been installed and a 1000 cubic metre per hour unit has been designed. Laboratory and pilot plant Filblasts have also been built.The reactor is a robust, compact in-line or end-of-line device and may be constructed out of a wide range of materials including wear and corrosion resistant alloys and ceramics. The Filblast Process may be applied to high temperature leaching of refractory gold ores and base metal concentrates.

Jan 1, 1997

By Bruno Sceresini

The Filblast Cyanidation Process incorporating intense high shear mixing, high gas mass transfer efficiency and high oxygen concentrations under conditions of elevated pressure has now been been successfully applied in gold cyanidation mills since May 1993. The first commercial unit had a slurry capacity of 110 cubic metres per hour. Since then 230 and 450 cubic metre per hour units have been installed and a 1,000 cubic metre per hour unit has been designed. Laboratory and pilot plant Filblasts have also been built. The reactor is a robust, compact in-line or end-of-line device and may be constructed out of a wide range of materials including wear and corrosion resistant alloys and ceramics. The Filblast Process may be applied to high temperature leaching of refractory gold ores and base metal concentrates. The development and application of the Filblast Gas Shear Reactor as a cyanidation tool has removed the constraints of plant size in cyanidation applications in mobile or readily transportable gold plants. A 250,000 tonne per annum fully modularised gold ore treatment plant with the Filblast and AARL Pump Cell as core technologies is nearing completion. This plant includes several novel features which are predicted to achieve widespread adaptation in modem cyanidation plants. This paper presents a briefreview of the development of the technology and the principles incorporated in the Filblast system. A number of case studies are presented which show significant financial benefits due to more efficient reagent utilisation, higher recovery and increased through-put.

Jan 1, 1997

By Bruno Sceresini

Prospectors and small scale mmmg companies have long expressed the wish for a highly mobile mineral processing plant. This is especially so in the case of gold mining as relatively small deposits can be highly profitable due to the relative ease of producing a marketable product when compared with the refming and marketing costs incurred with base metals. This paper will concentrate on gold ore treatment in fitting with the theme of the 1996 Randol Gold Forum but the principles may also be applied to base metal ores. The development and application of the Atomaer Filblast Gas Shear Reactor as a cyanidation tool has removed the con­straints of plant size in pulp cyanidation applications. KC Dodd and Associates, Consulting Engineers and Australian Mining Advisers, Pty Ltd, have designed a 1,000,000 and a 250,000 tpa fully modularised ore treatment plant. Various module configu­rations can be arranged to treat a wide variety of ores ranging from simple gold ores to gold-copper and base metal ores. This paper will limit the discussion to comparing the capital and operating costs of a conventional and a modularised 1 million tpa gold treatment employing a number ofnovel concepts which complement the compact, high capacity Filblast Cyanidation Process and the AARL pump Cell Adsorbers. The design described in the paper not only reduces equip­ment sizes and allows for rapid deployment of a sizeable capac­ity plant but also offers significant capital and operating cost benefits.

Jan 1, 1996

By Daniel P. Stare, Lucian P. Spiteri, Christopher M. Hallahan, James C. Myers

Buckeye Lake Dam was substantially remediated between 2015 and 2018 as a result of unacceptable dam safety performance. A permanent seepage cutoff, consisting primarily of a soil mixed cutoff wall (SMCW) with occasional sections of steel sheet piling, was constructed along the dam alignment. Closures were required at the terminus of the soil mix elements with existing structures or coffer cells, and at locations where new sheet piling was constructed parallel to the new soil mixed cutoff wall, creating a short circuit seepage path. The original proposed design to construct these closures included permeation grouting methods with chemical grouts. However, a combination of multiple chemical grout types, multiple grout pipes, and an extensive post-grouting verification program was required to ensure the design intent was achieved. After award of the project, the specialty grouting contractor elected to evaluate jet grouting as an alternative closure construction method. The advantages of the jet grouting option offered potential schedule and cost savings to the project as well as a superior product for seepage reduction, given the mixed soil conditions at the site. This paper presents an examination of the site conditions and project goals for the construction of the proposed closure elements for the rehabilitation of Buckeye Lake Dam. Descriptions of the original and alternative treatment methods are provided, with expected performance results. A description of the relative strengths and deficiencies of each method, as well as the feasibility and constructability of each method is provided. The implementation of the jet grouting program is presented, including a discussion of the design elements, quality control test methods, movement monitoring, and verification test methods. This paper also examines the risks associated with jet grouting and how those risks were mitigated during the grouting operations. HISTORY Buckeye Lake is situated approximately 28 miles east of Columbus, Ohio and is managed and operated by the Ohio Department of Natural Resources (ODNR) as part of the Ohio State Parks system. The lake is impounded by natural features that exist along the south and east banks of the reservoir, and by the embankment structure constructed along the north and west banks of the reservoir (see Fig. 1). The reservoir site was originally a natural swamp and the original purpose of the constructed dam and reservoir was to provide water to the Ohio and Erie Canal System. Several dam alignments and configurations were constructed during its early history; however, the original embankment is comprised of homogeneous earthen fill. The embankment is 15 ft (4.6 m) high and extends 4.1 miles (6.6 km) from the North Shore abutment along the east, continuing to the abutment at Lieb’s Island to the West. Several spillway and outlet structures exist along the embankment alignment. Most noteworthy are Seller’s Spillway and Amil Spillway. Fig. 2 is a Plan View of the embankment alignment and appurtenant structures at Buckeye Lake.

Jan 1, 2019

This paper explains why the valuation of mining assets is often a very different exercise from the valuation of the shares in the mining company which owns those assets. The fundamental reason for this is that mining assets, and the shares of the company which owns those assets have different risks. In order to properly value mining securities it is essential to: ò ensure all the different risks and other factors which impact on the value of the mining assets and the value of the shares are taken into account; and determine the extent to which the different risks and other factors are addressed in the value of the mining assets and the value of the shares so as to avoid double counting or not counting at all. If the alternative, but far from consensus, view is accepted that the correct valuation methodology to apply to shares in mining companies should be based on option pricing theory then conventional valuation practice of both mining assets and shares in mining companies will need to be fundamentally reassessed.

Jan 1, 1994

By Peter Kettle

This paper describes the performance of the copper industry over a period of some two decades and examines the theme that improvements in operating efficiency have not been matched by improved returns on capital. The financial performance of the copper industry is analysed using CRU's MICA database. Regression analysis indicates a two percentage point increase in operating margins but no increase in returns on capital. The gain in operating efficiency appears to have been mainly achieved in the mid 1980s. The investment boom of recent years has resulted in a rapid increase in the industry's level of debt and gearing ratio (now some 47%). Data on 44 copper mine projects is used to show the linear relationship between scale and capital costs. Typically new capacity costs some US$5,000 /tpy. The relationship between cash costs and capital intensity of projects is also plotted. The greater attention now being focused on efficient use of capital means that capital intensity rankings will become increasingly important in determining which projects go ahead.

Jan 1, 1999

By Henry Fernald

THE accounting system or bookkeeping methods of any company are principally the concern of that company and of those who are in control of its affairs. Its published financial report is, however, primarily intended for those who are not already fully informed regarding its operations and finances. Whatever may be the advantages of standardization of accounting and bookkeeping methods, it must be admitted that a company has a certain right to handle its accounts and keep its books and records in whatever manner may seem to it best adapted to its affairs, even though such methods may differ materially from those generally adopted by others. In its financial reports it should not, however, either ask or expect that the statements it makes or the terms which it uses will be given in its case a meaning and interpretation different from that which they are ordinarily considered to have inn similar reports and statements of other companies. The particular form and arrangement of such reports is a matter concerning which there may be much difference of opinion. It is of little importance whether current assets come first or last in the Balance Sheet, but it is important that there should not be included under this designation any items which are not properly current assets within the generally accepted meaning of that term. The extent to which stockholders or others interested are to be made acquainted with the full details of a company's business is a question which the proper authorities must in each case decide. It should, however, be recognized that there are certain facts regarding a mining company which must be set forth in a financial statement if it is fully to cover the conditions and affairs of the company. For example, a financial statement which does not include or is not accompanied by a statement of the ore reserves of the company does not fully set forth its financial condition. This is true whether the absence of such a statement of ore reserves is because it is not desired to make public the figures or whether it is because the ore reserves themselves are not definitely known or accurately measured.

Jan 1, 1928

By Henry Fernald

THE accounting system or bookkeeping methods of any company are principally the concern of that company and of those who are in control of its affairs. Its published financial report is, however, primarily intended for those who are not already fully informed regarding its operations and finances. Whatever may be the advantages of standardization of accounting and bookkeeping methods, it must be admitted that a company has a certain right to handle its accounts and keep its books and records in whatever manner may seem to it best adapted to its affairs, even though such methods may differ materially from those generally adopted by others. In its financial reports it should not, however, either ask or expect that the statements it makes or the terms which it uses will be given in its case a meaning and interpretation different from that which they are ordinarily considered to have in similar reports and statements of other companies. The particular form and arrangement of such reports is a matter concerning which there may be much difference of opinion. It is of little importance whether current assets come first or last in the Balance Sheet, but it is important that there should not be included under this designation any items which are not properly current assets within the generally accepted meaning of that term. The extent to which stockholders or others interested are to be made acquainted with the full details of a company's business is a question which the proper authorities must in each case decide. It should, however, be recognized that there are certain facts regarding a mining com-pany which must be set forth in a financial statement if it is fully to cover the conditions and affairs of the company. For example, a financial, statement which does not include or is not accompanied by a statement, of the ore reserves of the company does not fully set forth its financial condition. This is true whether the absence of such a statement of ore reserves is because it is not desired to make public the figures or whether it is because the ore reserves themselves are not definitely known, or accurately measured.

Jan 1, 1928

Some basic terms used in cost management and accounting include: - Cost. A sacrifice made to acquire goods or services, measured by the price paid. Technically, the sacrifice is called a cost until the benefits from the goods or services have expired, at which time the sacrifice is called an expense. In this text, the terms "cost" and "expense" are used interchangeably. - Revenue. An increase in the value of the firm resulting from the sales of goods and services. - Income. The excess of revenues over costs for a specified period. The term is often used with modifiers to indicate specific quantities on an income statement (e.g., pretax income; net income). - Activity. A measure of production work. Traditionally, physical production volume (tons of ore or units of product) has been used as the measure of activity. Other measures include direct labor hours, equipment operating hours, and quantity of materials or supplies consumed. - Responsibility center. A segment of an organization that is responsible for a specified set of activities. In mining, individual operating divisions can be treated as responsibility centers, known as profit or cost centers. Departments within a division are generally treated as cost centers. - Cost center. A portion of an organization having responsibility for achieving specified levels of cost. - Profit center. A portion of an organization having responsibility for achieving specified levels of profit (revenues and costs).

Jan 1, 1999

By William J. Potter

The current financial environment differs markedly from past commodity price expansions, which have benefited the mining industry. Deregulation, financial innovation, and the globalization of capital markets in the 1980s have altered financing and investing patterns. Investment bankers and smart money within the industry have recognized the alterations and trends that facilitate fee revenue and profitable growth. This paper profiles transactions exemplifying change and documents financing techniques or instruments that have developed during the past half decade, emphasizing equity in the global marketplace.

Jan 1, 1990

The Nagambie heap leach gold mine commenced production of gold in September, 1989. The mine,120km north of Melbourne in Victoria, Australia, was developed by Perseverance Mining Cor- poration Ltd, a junior Australian mining company, with no other operating mines. Gold production to December 31, 1990 was 47,621 oz. The mine is now producing at the rate of about 45,000 oz per year. As of February 28, 1991, resources at the mine are 5.1 million tonnes measured, at 0.65g/t Au while reserves were 1.65 million tonnes at 0.86g/t Au of proven, heap leach ore, plus 0.37 million tonnes at 0.40g/t Au, of dump leach ore. Metallurgical recoveries expected are 80 per cent for the heap ore and 60 per cent for the dump ore. Perseverance Mining Corporation was listed on the Australian Stock Exchange on April 2, 1987, after a capital raising in March that year. At this time the company's issued capital was 4 million ordinary 25ó shares, 3 million of which were issued to the public to raise $0.75 million.

Jan 1, 1991