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By D. P. Harding

Quick, inexpensive and accurate mineral-phase identification is of utmost importance to applied mineralogists. The precise relationship between the intensity of measured backscattered electrons in a scanning electron microscope and the average atomic number of the specimen is still argued. Nevertheless, much can be gained by using backscattered electron images to identify mineral phases in a specimen. An application was developed to facilitate this method and makes it a practical, inexpensive and valuable option in many mineralogical investigations. Keywords: Mineral identification, Scanning electron microscope, Backscattered electron detectors

Jan 1, 2003

By Orris C. Herfindahl

Every few years we are treated to a battle over trade policy when the Reciprocal Trade Agreements Act comes up for consideration. In 1962 it is especially appropriate to consider the problem of mineral import -policy and the closely related problem of general import policy, for this year's struggle is different from those of the past in two ways. First, proposals have been made which are a substantial departure from past trade agreements legislation, and second, the formation and growth of the Europe Economic is Community may have an important bearing on the kind of legislation that is adopted. But this anticipates what is to come later. My task is to examine the problem of mineral import policy, although we shall find soon enough that general trade policy must be considered in order to get an indication of what is in store for minerals.

Jan 1, 1962

By A. M. Gaudin

In the first place, let me thank you for inviting me to appear before you today to speak to you on "Mineral Industry Problems - Present and Future". It is a distinguished honor for me to have this opportunity, and I am highly appreciative of this distinction. The beautiful surroundings of Gatlinburg and the pleasantness of a summer occasion are a wonderful tonic for all of us, yet they should not blind us to the seriousness of our Industry's problems No doubt, because of my past appearances before members of the Society of Mining Engineers, at which I discussed wholly scientific topics, or research in the Applied Sciences, you may be expecting me to revert to these subjects. But I intend to venture in a field that is new to me, yet old to all of us, the field of Economics.

Jan 1, 1962

By Alfred Jr. Petrick, William A. Vogely

INTRODUCTION The scope of mineral finance extends beyond the economic aspects of property evaluation to all of those activities involving acquisition and utilization of funds with an objective to optimize the value of the firm. It must, therefore, en- compass consideration of the overall financial goals of the firm, decisions involving external versus internal growth and domestic versus foreign investments, management of working cap- ital, efforts to minimize the cost of capital, and decisions with regards to the instruments of long- term debt and equity financing. The scope of this section is limited to considerations of special interest to the mineral or petroleum engineer, which include the following aspects of mineral finance: (1) The technical aspects of mineral or coal property or oil and gas reservoir evaluation which provide the basis for estimation and forecasting of revenues and costs. (2) Estimation and forecasting of costs and prices in a inflationary economic environment. (3) Calculation of cash flows which model .. , the investment in minerals, coal or oil, and gas. Such models require assumptions as to the timing of cash flows, escalation of capital and operating costs, base prices, and escalation, the tax regime, royalties, division of profits and the economic aspects of loans. (4) The role of discount rate in the economic analysis of an investment which requires consideration of the opportunity costs of the firm, cost of capital, risk premiums. (5) Risk analysis including application of the concepts of conditional net present value, expected value, and risk preference as well as the application of the techniques of sensitivity and simulation. (6) Selection of application criteria for in- vestment decision making. (7) Capital structure with particular reference to the effect of debt financing. (8) Consideration of sources of funds utilized by the minerals industries. (9) Long-range planning including portfolio analysis. This section is limited to principles, methodologies, and trends in mineral investment, finance, and long-range planning in the United States with a perspective from the year 1984. Consideration of the key concepts is supplemented by case examples of investment risk analysis and financial structure. Important factors affecting mineral investment evaluation during the 1980s include volatile metals prices, cost inflation, and the introduction of techniques requiring the computer and its capacity for improved technical and economic analysis into the hands of those who know most about the industry. The personal computer is replacing the calculator on the desk of the individual analyst and is rapidly becoming a required tool for the study of engineering and economics. Examples of change brought about by the micro-computer include greatly improved techniques of cost estimation, wider application of the computer for project analysis, computer graphics, reserve estimation, geostatistical analysis, mine design and other techniques that capitalize on the ability of the computer to handle

Jan 1, 1985

By I. J. Wu

China’s land area, comparable in size to United States or Canada, contains diverse geological environments and mineral resource potential. The diversity in geological environments is such that the potential for developing many world-class mineral deposits in China is good. However, China’s mining sector was not open to foreign investment until the1990s. The long-term prospect for Chinese resource development is attractive because of China’s enormous population and cumulative demand for minerals. Approximately 33 foreign mineral companies, including 11 major internationals, are to various degrees active in China. Chinese mining laws and regulations pertaining to joint ventures with foreign companies are, from the international investment prospective, evolving slowly, but positively. This positive trend is continuing under the current government reform process, which is moving China towards a freer market economy. Although improving the enforcement of relevant laws and regulations is an ongoing process, the environment for mineral investment and joint ventures is increasingly more accommodating to foreign companies.

Jan 1, 2000

By Ralph Loyd

One of the principal responsibilities of the California State Geologist is to provide local governments with maps and information regarding mineral resource occurrences within their jurisdiction. The primary objective of this effort is to furnish basic data that is essential in planning for and accommodating wise development of mineral deposits that are important to the economic well-being of the region, state, and nation. Local government agencies are required by law to incorporate the information provided by the State Geologist into their general plans and formulate mineral resource management policies that emphasize conservation and development of mineral deposits. The Mineral Land Classification program was initiated by the State Geologist in 1977 under authority of the California Surface Mining and Reclamation Act (SMARA). To date, about 33,000 square miles of land have been classified for mineral resource potential. Most of the mineral land mapping has been conducted in three principal areas: (1) metropolitan areas of the state where urban encroachment has greatly diminished available supplies of construction aggregate; (2) Sierra Nevada foothills, a region that is undergoing dramatic population increases; and (3) the Mojave Desert and Great Basin regions, where large Federal land withdrawals are pending that could preclude mining. Mineral land classification studies address the overall mineral potential of a region through the identification of local and regional geologic factors that control or influence the formation of mineral deposits. These studies are field-intensive surveys that enable project geologists to gain first-hand knowledge about the nature and distribution of mineral deposits in a given area and portray that information accurately in map form. This paper summarizes the progress made in the Mineral Land Classification program in the metropolitan, Sierra Nevada foothills, and the Mojave Desert/Great Basin regions of California. Selected projects from each area are discussed in detail.

Jan 1, 1995

By P. G. Tzeferis

Factory beet molasses media were used as cheap sources of sucrose for microbial leaching of Greek nickeliferrous laterites using strains of Penicillium and Aspergillus sp. Nickel recoveries of up to 62% and cobalt recoveries of up to 50% were obtained by leaching in a two-phase system in which bioacids were produced by fungal metabolism in molasses ferrocyanide pretreated media. The addition of potassium ferrocyanide to the molasses substrates prior to leaching was found to have a beneficial effect by increasing the level of citric acid bioproduction, thus improving the leaching efficiency of the fermentation liquid. The metals known to interfere with citric acid production (i.e., Fe, Cu, Ca and Mn) were those most efficiently precipitated. Considering the much lower commercial price of molasses in the industrial market compared to sucrose and glucose carbohydrate media, molasses could prove to be a promising alternative, despite the cost of the required pretreatment.

Jan 1, 1995

By G. Barbery

In Mineral Processing, the objective of most processes is the separation of mixtures of minerals, which are originally associated in composite particles. Feed preparation processes grinding for instance, which take place before beneficiation or separation processes do not usually break particles at the boundary between mineral phases. They produce composite ("middlings") as well as liberated particle. It is therefore necessary, in a particulate system, to determine the proportion of particles which are liberated as well as, ideally, the size distribution of minerals which remain associated in composite particles. Up to now, there has been a lack of experimental techniques to characterize completely composite particulate systems. Heavy liquid separation which is commonly used to obtain information of this type can only be applied to simple binary cases for which one mineral has a low density (lower than e.g 2.8 ). The technique which is proposed in this paper involves the measurement of parameters on polished sections of particles mounted in a matrix, and the use of mathematical transformations to reconstruct in three-dimensions the information obtained from these measurements .

Jan 1, 1977

By R. P. King

INTRODUCTION It is now 21 years since Wiegel and Li published their paper on a random version of Gaudin's model for the mineral liberation phenomenon (Wiegel and Li, 1967). This paper was to revitalise interest in North America in one of the most fascinating, difficult and important problems in the field of theoretical mineral processing. Gaudin had many years previously (Gaudin, 1939) already presented a penetrating analysis of the problem and Wiegel and Li based their analysis very closely on the Gaudin model but they realised that the indeterminate geometrical structure of mineralogical materials demanded that only probabilistic models could provide the necessary quantitative information when working with real materials. They proposed and solved a randomised version of the Gaudin model but retained the essential geometrical simplicity of cubic mineral grains and a cubic fracture pattern. Although their model met with some limited success it was to be superseded in due course. During the 1940's and 1950's the classical field of geometrical probability spawned the mathematical discipline of integral geometry and as early as 1965, Bodziony (1965, a,b) showed that the techniques of integral geometry could accommodate the problems associated with the indeterminate nature of the geometrical mineralogical structure, provided that these were couched in probabilistic terms. In particular he showed that the quantitative description of the comminution process and that of liberation could be decoupled with the resulting economy of effort. This idea has profoundly influenced the course of research in liberation theory and has greatly facilitated its application and the measurement of liberation in a practical way. Bodziony demonstrated also that any theory that required the specification of the mineral "grain

Jan 1, 1989

By Timothy J. Napier-Munn, David M. Weedon

A model of mineral liberation was developed using back calculation techniques to determine breakage/liberation parameters in a similar manner to the way breakage parameters are determined in the Population Balance Model (PBM). Comminution and liberation data was collected from grinding mills operating at Pasminco lead/zinc mine Broken Hill, and Mt. Isa Mines copper concentrator, Mt Isa, Australia. Laboratory scale single particle breakage tests on ore samples from these sites were undertaken using a twin pendulum breakage device. Break- age/liberation parameters were then determined for several mills using back calculation techniques. The liberation/breakage parameters were then used to simulate mill liberation performance under varying conditions.

Jan 1, 1996

By Jack E. Thompson

Thank you Tom and JM for that nice introduction. The remarks I am about to make rely on a large way on comments made by Barrick's Chief Counsel, Patrick Garver, to an internal meeting of Barrick's senior staff. I plagiarized so much from his notes that I thought that I should provide attribution. I did get his consent to borrow so freely. What I have done is take his general comments and used my conversations with CEO's and other participants in the industry to enhance the message with concrete examples that underscore the points I wish to make. What you are about to hear is my personal view – I am not speaking as a representative of any company. With that introduction, now would be a good time to give you the main theme of my talk: The SEC should change its rule making to a more public cooperative approach. If that were to happen the SEC would avoid some of the harm it has been doing to the companies in this sector and the very shareholders it seeks to protect.

Jan 1, 2003

By Frank R. Field, Joel Clark, Walter C. Labys, William A. Vogely

Mineral models provide a systematic and comprehensive approach for analyzing and fore- casting the behavior of mineral markets and industries.' They also permit the analysis of a wide range of policy decisions. Obviously such models cannot capture all of the intricate relationships that shape the behavior of a mineral market. However, such models have become extremely useful and in many cases support the decision making approach of judgmental analysts. They tend to narrow the range of likely outcomes and thus reduce the risks and uncertainties of investing, trading, and speculating in minerals. Mineral models provide not only answers to "what-if" questions, they also inform analysts of the benefits and costs associated with mineral investment decisions. More recently they have been applied to specific mineral issues of the possible impact of buffer stock stabilization schemes and of import supply restrictions. Mineral Models Defined Because mineral models are so diverse, we must begin with a fairly broad definition. A mineral model is a formal representation of a mineral market, industry or system where the behavioral relationships included reflect the underlying economic and engineering factors as well as the political and social institutions. Of ten, but not always, a mineral model will consist of some combination of the following components: demand, supply, inventories and prices. Modeling of demand behavior normally begins with an interpretation of basic demand responses to prices and income (i.e., the associated price and income elasticities). Price elasticities vary among different minerals and among their diverse uses. They tend to be lower for minerals without close substitutes than for those where such substitutes exist. In addition, these elasticities vary with time as well as with the actual excess demand or excess supply. Variations like these, coupled with the relative instability of prices for a number of minerals, make explanations of demand behavior difficult. The degree to which demand responds to changes in income depends on the income elasticity of the end products to which the minerals serve as inputs. Those products with a relatively low income elasticity tend to experience proportionally smaller swings in sales than those with higher elasticities. The transmission of demand cycles to minerals producers comes through a series of stage-of-process effects. Demand measurement also is influenced considerably by mineral substitution patterns. The cross-price elasticity of a competitive or complementary commodity also varies with minerals, markets, and time. Where minerals easily substitute for one another, as in the case of cop- per and aluminum in electrical conductor applications, cross-price elasticities are relatively high. Modeling of mineral supply behavior normally involves consideration of resource development, economic conditions, geologic

Jan 1, 1985

By J. Groff

The Getchell and Twin Creeks mines are located along a north-northeast trending structural zone in Humboldt county, Nevada approximately 40 miles northeast of the town of Winnemucca. Gold mineralization at the Getchell mine is represented principally by sulfide-rich ores, which contain significant amounts of realgar and\ orpiment, with the gold being recovered through processes which involve pressure oxidation. In contrast, oxide ores are currently being mined and processed at the Twin Creeks mine although large reserves of sulfide ores, some of which contain orpiment-realgar-stibnite, have been defined (Bloomstein et al., 1990). The Getchell and Twin Creeks mines represent major gold orebodies but very little has been published pertaining to mineral paragenesis and the characteristics of ore-forming fluids for these deposits.

Jan 1, 1994

By Kenneth R. Hancock

The importance of "Mineral Pigments" can best be shown by noting that the world production is estimated to be in excess of 47 billion kilograms (52 million st). This quantity if pack- aged in the common 22.6 Kg (50 Lb.) bag and placed end to end would circle the world over 500 times. This world production figure is based on a broad concept that pigments, extenders, and fillers have essentially similar functions. In this paper mineral pigments are products produced synthetically or from selected minerals and through pulverization have characteristics of pigments.

Jan 1, 1985

By K. Nielsen, V. Bauer

"The paper presents a brief overview of the long mining history and the more recent political development in the Slovak and Czech Republics as well as in Norway and Sweden. Mining used to be very important sources of economic wealth in the four countries, but in today’s economy does exploitation of non-energy minerals usually account for less than one per cent of the GNP. The paper will discuss and compare the mining legislation, land use planning and mineral policies framework in the four countries and how this may influence sustainable management of mineral resources including planning for mineral supply, landbanks and sterilisation of resources. The paper will then identify some positive and negative elements in each country’s political and administrative framework."

Jan 1, 2005

By Anthony Leddin, Gillian Dooley

This paper is concerned with mineral policy in Ireland and how it might be improved to encourage more exploration and investment in mining in the country. The approach is to first outline the main desirable characteristics of a comprehensive national mineral policy document. This aspirational document is then used to assess the current regulatory, legislative and fiscal frameworks for mining in Ireland. The analysis also contains a brief account of the history, structure and characteristics of the mining industry in Ireland. The main focus of the paper is to identify those aspects of the existing framework that erode Ireland’s attractiveness to mineral investment and to suggest policy improvements.

Jan 1, 2005

By D. J. Shields

The goal of public policies is to connect desired ends with practical means toward their achievement. How the desired ends are determined, and whose goals and objectives they incorporate, depends upon the culture and political system of the country in question. With few exceptions, policies change over time to reflect changed perspectives and understanding of the world around us. This is true regardless of the policy area in question. Thus, how societies view and manage their mineral resources has evolved in response to public attitudes, societal needs, economic circumstance, cultural perspectives, political orientations, technological advancements, and geological knowledge. In this paper we examine how the scope of concern has changed for mineral policy. We then review the overarching issues that have in recent years been considered essential components of mineral policies. We point out how neoclassical microeconomics has influenced recent policy design. We then use a market flow diagram to illustrate how policies can be focused at specific market issues. We next discuss mineral resources in the context of sustainable development. We identify issues that become relevant when the frame of reference is enlarged beyond ensuring supply and capturing economic rent. We show that policy based solely on neoclassical economics may not be able to effectively incorporate these issues.

Jan 1, 2007

By Camillo Premoli

Namibia is one of Africa's newest nations. A German colony until 1915, it then became a South African protectorate until 1990, when it gained independence after an armed struggle that lasted more than two decades. However, no trace of past bitterness can be found today in the capital, Windhoek, or in the countryside. Namibia is now one of the safest parts of Africa. Namibia's industrial base and infrastructure have been untouched by war. Swapo, the ruling party, has embarked on a successful policy of reconciliation and economic development. The GNP per capita is a surprising $1500 (from the World Bank), one of the highest in Africa. Namibia's population stands at 1.3 million, including about 100,000 whites. Namibia is a very sparsely populated country (1.7 inhabitants per km2). About 70% of the people are farmers. Namibia has a surface area of 824,232 km2 (318,261 sq miles), about the size of France and Germany combined. The semi-arid climate and generally flat morphology make the country well suited to mineral exploration. About 40% of the country presents abundant rock outcrops. The rest is buried under the Kalahari sands. However, this cover in most of the country hardly exceeds 200 m (655 ft), and Australian technology has shown that large mineral deposits (Roxby Downs) can nowadays be found at even greater depths. Mining is Namibia's largest industry. In 1991, it accounted for 22% of the country's GDP, about 70% to 80% of its exports by value and 25% of internally generated government revenues. The Ministry of Mines and Energy (MME) is responsible for formulating and implementing national mineral policies. This agency has recently introduced legislation aimed at encouraging new and long-term investment in the mineral sector. The variety of Namibian mineral resources, both metallic and nonmetallic, is rivaled by few countries worldwide.

Jan 1, 1994

By F. F. Aplan

Mineral process engineering is a small but important part of the nation's raw material industry. Minerals are usually processed in large plants of high capacity, at low cost, using few engineers and operators, and at an ever-increasing level of plant sophistication. The magnitude of the mining industry is huge, with about 4 Gt (4.5 billion st) of ore, coal and industrial minerals mined annually in the United States. Industries such as construction, manufacturing and power generation rely heavily on a strong US resource base to maintain a competitive edge. Though rooted in classical chemistry, geology, physics and mathematics, a mineral process engineer must be trained in the science and engineering required to process raw materials. A modern mineral processing program still stresses the traditional aspects of the profession. But it also emphasizes particle technology, applied surface chemistry, chemical processing of ores, solid-fluid separations, process and equipment modeling and optimization, materials handling, personnel management, maintenance and environmental and health aspects. In such areas as particle technology and some aspects of applied surface chemistry, mineral processing academic programs have taken a leadership position in supplying specialists to a variety of other industries. The objectives of a mineral processing program are: • to furnish personnel to support the basic raw materials industries (undergraduate programs); • to provide a research and development base for industry (graduate programs); and • to provide expertise in particle technology, applied surface chemistry and environmental programs for other industries (undergraduate and graduate programs). In the United States, mineral process engineering programs have historically been associated with mining and metallurgy departments. The recent movement of metallurgy programs away from primary processing towards materials science has created the need for a new accommodation.

Jan 1, 1992

By Gordon E. Ager

A technique for the synthesis of mineral processing flowsheets from laboratory batch test data is described and examples of the application of the procedure are given. The procedure requires the collection of kinetic data, the optimization of the flotation time in each separation stage, then simulation of the material balance for a continuous circuit.

Jan 1, 1989