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By Robert Halupka

The industrial minerals sector represents a broad range of products involving a variety of technologies serving a diversity of markets and end uses. Unit values of products vary widely, reflecting the peculiarities of each product/market sector. Generalizations are therefore understandably difficult to make and borrowers may need to take extra time to "educate" lenders on the key aspects of their business and industry sub-sector. This paper will examine the factors and the thinking that lenders apply when considering financing proposals to companies in the industrial minerals sector. If you understand the lender's perspective and their concerns, then you can make better use of your own time and resources when arranging financing for your company or project.

Jan 1, 2001

By Nicola Robjohns, Kenneth A. Grace, Jane Spooner

"The important volume end use sectors for the rare earth elements and yttrium continue to be in steelmaking, petroleum cracking catalysts and glass polishing. The market sectors which may provide future high volume demand, to replace the older sectors where demand has declined over the past decade, include magnets, automobile catalysts, ceramics and superconductors. Increases in production capacity in all major rare earth producing countries are expected to restrain large price increases for high purity rare earth oxides over the short term. A sharp increase in demand for yttrium in advanced ceramics and superconductors would lead to a shortage in separation capacity, however, and to a corresponding rise in prices for separated rare earths.IntroductionWhile visiting the Geology Department of the University of Toronto in 1981, Professor Lu from the Institute of Geochemistry of Academia Sinica at Gweiyang in China introduced one of his seminars with the observation that in China, rare earths are not rare at all.Indeed, while being rare in terms of abundance as measured by, say, the Clarke scale, the rare earth elements, like many other low abundance elements, are subject to geological, geochemical and mineralogical concentration.The rare earth elements comprise the fifteen inner transition elements of Group IIIB, Period 6, of the periodic table, from lanthanum to lutetium (the lanthanides), as set out in Table 1. The rare earths constitute a distinct group as they have extremely similar chemical characteristics due to the uniformity of their outer electron shells. The element yttrium is usually, by convention, included in the rare earth group as it occurs with the rare earths in nature and has properties very similar to them.The rare earths are divided into two subgroups, the ""light"" rare earths, made up of the first seven elements of the series, lanthanum to europium, and the ""heavy"" rare earths, comprising the remaining eight elements, gadolinium to lutetium, plus yttrium. These two subgroups are also referred to as the cerium subgroup and the yttrium subgroup, respectively. The subdivision is based on differences in the atomic radii resulting in somewhat different properties for the two subgroups."

Jan 1, 1991

By C. T. Dzgoev, S. S. Gudkov, IRGIREDMET JSC, S. G. Schtoick, A. V. Yepiforov, S. V. Balikov, I. I. Yevtuschevich

The pressure oxidation (POX) and pyrometallurgical process comprises POX of gold containing sulfide and polymetallic lead-zinc concentrates prior to reduction smelting of POX products to generate a lead-silver-gold alloy. Refined lead and gold-silver alloys are then obtained using conventional processes. Zinc and other base metals are recovered from the POX solution. In the course of POX, zinc dissolves in the solution and lead concentrates in a solid residue in the form of sulfate compounds. Sulfur forms the major iron sulfates and jarosites. In order to dissolve sulfur and arsenic from solid residues to the solution, the slurry hot curing was carried out at the temperature of 95°C within 2 hours. After filtration of the slurry, zinc was recovered from the solution. The resulting cake was washed with water and subjected to hot alkaline treatment. After alkaline treatment, the cakes were blended with fluxes and subjected to reduction smelting to generate lead concentrate containing precious metals. This concentrate was refined to obtain refined lead and gold-silver alloy. After iron and arsenic were removed from POX solutions using sodium carbonate, zinc was precipitated as carbonate. After thickening and filtration, zinc precipitate was roasted to generate saleable zinc oxide. Using this process, the recoveries of values to saleable products were 97% Au and 95% Ag to the alloy, respectively, 91% Pb to refined lead and 5% Pb to lead and antimony alloy and 94% Zn to zinc concentrate. The features of the technology is that it has high recovery indices of precious and base metals to saleable products and can be used to process various polymetallic ore and technogenic raw materials.

Jan 1, 2016

By J. E. Tupper

"This paper will discuss strategies for the introduction of computer technology in the mine environment. More specifically, it will focus on issues such as: (a) make or buy; (b) programmer less mines; and (c) support from corporate groups.The paper relates these strategies to systems for mine operations. These will be illustrated by considering the implementation of some phases of these systems at Teck Corporation.IntroductionThis presentation addresses some of the major considerations in a strategy for mine computerization and then relates these considerations to the computerization cycle and Teck Corporation.Strategy is defined as a conceptual framework or plan to accomplish a goal. For purposes of this paper, the goals can be more simply defined for operational purposes as either increasing revenue or decreasing costs.The strategy will allow us the framework for measuring tactical decisions such as computer and software acquisitions.The Mine Life CycleTo start with, let us look at the mine life cycle from a computer systems point of view:-Exploration-Property Development-Feasibility-Construction-OperationFrom a systems point of view, the exploration cycle is oriented to geophysical and geochemical computing. Property development starts with drilling and building the geological data base. The feasibility cycle includes all stages of evaluating the decision to proceed with mine development: ore reserve calculations; mine planning; and financial projections. Construction includes project management and project accounting systems. Systems required for operation are those needed by personnel at the mine site."

Jan 1, 1982

By A. Ansari

Standard depressants used in the selective separation of copper and molybdenum sulfides by flotation pose environmental and health hazards. In this investigation, the floatability of chalcopyrite and molybdenite in the presence of six well-characterized lignosulfonates was studied through Hallimond tube flotation and adsorption tests. The results define the physicochemical conditions (lignosulfonate type and dosage, pH, presence of ions) for possible selective separation of molybdenite from chalcopyrite. Dissolved polyvalent cations, especially calcium, appear to serve as "activators" for lignosulfonate adsorption on both minerals. From this point of view, the use of lime as a pH modifier is not always appropriate for optimum selectivity since high dosages of lime to produce high pH tend to indiscriminately depress both sulfides.

Jan 1, 2006

By S. Jayasekera, A. M. T. S. Bandara, J. Kyle, E. Koenigsberger, L. Koenigsberger

The extraction of rare earth oxides from fluoroapatite rich phosphate concentrates often involves a weak acid leach of fluoroapatite and a sulphuric acid bake of the leach residue followed by water leach and precipitation to obtain an intermediate product. The main aim of this study was to determine and rationalize the solubility of rare earth metal ions in synthetic solutions representing various process liquors at the temperatures 40, 60 and 80oC. The liquors contained different acid and metal ion concentrations with respect to sulphuric acid, phosphoric acid and sulphate salts of sodium, magnesium, aluminium, potassium, calcium and iron(III). A solid of mixed rare earth carbonates was used as the source of rare earth metal ions. The solubility tests and characterization of solids using XRD were conducted at Murdoch University laboratories as part of the process development for the Arafura Resources Nolans rare earth project. The composition of initial carbonate solids and the solids and solutions formed after saturation were analysed for rare earth and other elements at TSW Analytical Laboratories in Perth using ICP-MS and ICP-OES. The precipitated solid in sodium-rich acidic sulphate solutions is the double salt NaRE(SO4)2 based on the solid assays. However, in acidic solutions free of sodium or of low concentrations of sodium the precipitated solid appears to be RE2(SO4)3.

Jan 1, 2014

By Neillm Alastair S.

"This paper looks at what has happened in the past decade in the rare earth industry, particularly for those companies outside China trying to develop alternative projects to the Chinese dominated supply chain. The rare earth industry has gone through a metamorphosis over the past decade. The industry was basically unknown outside China until overnight it became the next hot topic on the financial streets of Canada and Australia. Suddenly various junior miners shifted from uranium and other out-of-favor commodities to rare earths as funds were easy to access from an investment community that did not understand the complexities of the space. The initial funding was done on traditional junior mining metrics of grade and deposit size. This has morphed over time to:1) Lights versus heavies2) Making a concentrate3) The importance of separation4) Off-take agreementsAt the peak of the market frenzy certain flagship operations were built using the “Not Made in China” moniker. Unfortunately certain errors were made during implementation, which are finally coming to the surface and making the rest of the pack wondering what will happen next. A review and update of some of the mistakes made and lessons learned will be discussed.BACKGROUNDAbout ten years ago awareness started to form around the rare earth industry and various groups recognized that because of the closure of Molycorp, Mountain Pass, and the dominance of China, there was a risk of uncertainty of reliable supply. This was not news for those active in the industry like Rhodia (now Solvay), the Japanese, South Koreans and other key consumers but to others it was like a light went on and rare earths became the new “.com” trend for investment banks, investors and some mining companies looking for the next hot topic.In the late 1990’s Molycorp accounted for around 20-25% of the world’s supply of rare earths, mostly lights (La, Ce, Pr and Nd), with small amounts of heavies from other sources. Then environmental issues forced the closure of the operation at Mountain Pass. Within six months China had increased production to plug the gap in supply. Around that time China was developing a strategy to leverage their position in rare earths and implemented a series of regulations to increase the value added component of rare earths inside China."

Jan 1, 2016

By Rodnei Graça, Jorge Silva Bettencourt, Lena Virgínia Soares Monteiro, Baruch Spiro, Tolentino Flávio De Oliveira

Abstract - The Vazante Mine is located in the Vazante District, the largest zinc district in Brazil. The Vazante deposit consists dominantly of an unusual willemitic ore. Small sulfide bodies are tectonically imbricated with the willemitic ore, within the Vazante shear zone. Structural styles of deformation and petrographic and isotopic evidence indicate that willemitic mineralization and deformation occurred synchronously during the Neo-Proterozoic. Various generations of hydrothermal veins and hydraulic breccias may pre-date, accompany and overprint the mineralization. Ore-formation temperatures are deduced from stable isotope geothermometry and mineral chemistry of both sulfide bodies and willemitic ore. Temperatures during the main stage of mineralization range from 206°C to 294°C (willemitic ore) and 317°C (sulfides), and reflect the prevailing metamorphic conditions within the shear zone. The fluid from which the gangue minerals of the sulfide bodies precipitated (at 250°C) had an oxygen isotopic average value of ?18O = +19.4‰. This value appears to reflect the interaction of metamorphic fluid with the carbonate rocks of the Vazante formation. At 250°C, the fluid in equilibrium with the vein mineral phases and willemitic ore assemblage exhibits a uniform oxygen isotopic composition, with an average value of ?18O = +11.5‰. The positive linear covariance of ?18O and ?13C ratios of the carbonates is most likely due to the mixing of metamorphic and meteoric fluids. The ?34S values of sulfides indicate a direct crustal origin for the sulfur. It is suggested that the sulfur is largely derived from pre-existing sulfide bodies and has been transported by metamorphic fluids. The willemitic ore may have originated from the precipitation of metal in sulfur- poor fluids under oxidized conditions, within the Vazante shear zone.

Jan 1, 1999

By AN. Kumar

Two fabrication stages in the manufacture of pipelines are identified as causing significant deterioration of the steel plates, namely cold bending and welding. The objectives of this work include quantitative assessment of the degradation of the quality of the steel plate by the loss of fracture toughness, and an estimation of the safe working pressure. The study was conducted on three API grade steels: X42, X46 and X60. After cold bending by the UO technique, various welding technique were employed for joining of the bend plates along the pipe length. A crack-tip opening displacement parameter (CTOD) was used at the onset of initiation and at the first load maxima as the criterion for assessing the toughness degradation under various fabrication stages and regime (such as WZ, HAZ and parent body). In addition, strength, hardness and impact energy values were determined to check the degree of degradation. Microstructural and microfractographic investigation of the fractured samples were also carried out in the scanning electron microscope (SEM). X60 grade steel plate suffers from CTOD toughness loss by around 38 and 55% after welding and cold bending, respectively, for the conditions studied. A combined effect of the two stages results in a loss in toughness by around 70% for the same steel. In X42 grade, the loss in impact energy ranges from 78 to 35 J due to electrical-resistance welding study (ERW). Crack resistance curves are also obtained for the steels to study the crack growth resistance behaviour and to supplement the information on crack initiation behaviour. The orientation of the pearlite banding, as observed on the fracture plane with respect to notch front and applied loading direction appears to have a strong influence on the microvoid-coalescence mechanism of fracture as well as the toughness values. An integrated analysis of the performance of pipelines, considering all these key factors, is discussed.

Jan 1, 2005

By George P. Demopoulos, Yan Zeng, Zhibao Li

Precipitated silica is marketed with a rising demand as reinforcing filler in the rubber industry and as a potential raw material for the synthesis of lithium-ion battery electrodes. Due to an awareness of the environmental impact of the existing processes for the production of precipitated silica, a green and sustainable process was proposed by using sodium bicarbonate (NaHCO3) as an alternative to sulfuric or hydrochloric acid in the precipitation reaction with sodium silicates. The use of NaHCO3 allows for better control of the supersaturation and pH to form silica with desired quality. Additionally, Na2CO3 solution as the process by-product is recyclable because it could be recovered to produce NaHCO3 by absorbing CO2. The solubility of sodium metasilicate nonahydrate (Na2SiO3·9H2O) in the Na-CO3-HCO3-OH-H2O system was measured using a dynamic method in the temperature range from 288.15 to 308.15 K. It is found that the solubility of Na2SiO3·9H2O decreases with increasing concentration of either Na2CO3 or NaOH over the investigated concentration range. With the aid of the OLI platform, a chemical model for the Na2SiO3-Na-CO3-HCO3-OH system was established with newly obtained interaction parameters of the Bromley-Zemaitis model by regression of experimental solubility data. The new model predicted the solubility of Na2SiO3·9H2O in multi-component systems with good agreement and was used to conduct a preliminary feasibility study of the new process.

Jan 1, 2015

By Arthur Notman

In view of the alarm expressed in many quarters over the increased production of copper to come from Canada and Africa in the future, it is of interest to study the history of the principal producing districts of the world and to attempt to forecast the future part to be played by them. Tables 1 and 2 record the world production and that of the United States, together with their respective rates of increase, both in percentage and actual amounts. The important point in this record is the decline in rates of increase for both the world and the United States, but more particularly in that of the latter, since 1881. The increase for the United States in the last decade is less than that for any decade since 1881, and is only 20 per cent of that for the decade 1911-20. The increase for the world is less than that for the two preceding decades, and is only about 65 per cent of the war decade 1911-20. Referring to Table 1, the decade 1871to1880 showed an increase of 32.l per cent in the world's production, which was the low until the last decade, ending 1930, which shows an increase of only 24.5 per cent. These decades both represent periods of economic stress following wars. In the first case the recovery was very sharp, the percentage increase in 1881-90 reaching a high of 86.4 per cent. It would seem dangerous, however, to assume that a similar high will be reached in the next ten years, because of the severity of the depression brought about by the Great War and the probability of its influence extending well into the next decade.

Jan 1, 1931

By W. E. Coates

The social ecology of surface mining in urban areas is illustrated by a case study of a recent application for the opening of a new gravel pit in the city of Guelph, including the design of a progressive extraction-rehabilitation sequence for the property, investigation of the ecological impact of the proposed operation, history of the application procedure for a zoning change and the relationship of the operating plan to provincial legislation controlling surface mining.

Jan 1, 1972

By W. S. Szolga, M. Moser, M. D. Soderstrom, L. Cohen

"CYANEX® 272 is a phosphinic acid-based solvent extraction reagent used commercially since the early 80’s to recover and purify cobalt from sulfate solutions. Historically, the design of CYANEX 272 circuits has involved the selection of an optimal pH profile during pilot-scale testing using mixbox pH control. The desired pH profile is required to be carefully controlled in the same manner during commercial operation. To assist operators in the design and optimization of their circuits, Solvay developed CYANEX 272-specific solvent extraction modeling software, which has enabled determination of the ideal pH profile and staging configuration. Solvay’s recent advances in modeling capabilities have allowed the simulation of circuits without direct mixbox pH control. Modeling has indicated that circuits operated without direct pH control can achieve the desired metal separation while simplifying the commercial operation significantly. This paper reviews a number of potential circuit configurations for the use of CYANEX 272 and demonstrates the separations achievable under the right design and operational conditions, some of which have historically been considered too difficult.INTRODUCTION CYANEX® 272 is a phosphinic-acid based reagent designed specifically for the separation of cobalt from nickel by solvent extraction from weakly acidic sulfate solutions (Rickelton, Robertson, & Burley, 1982; Rickelton, Flett, & West, 1984; Rickelton & Nucciarone, 1997). Following commercial introduction in the 1980’s, CYANEX 272 has been used in a number of hydrometallurgical flowsheets for cobalt purification and/or recovery. CYANEX 272 metal extraction occurs by means of a cation exchange mechanism. Extraction of a divalent metal ion M2+ is represented by the following equation where RH represents the CYANEX 272 ligand and MR2 represents the ligand-metal complex."

Jan 1, 2017

By Scott A. Trebilcock

Nautilus Minerals Inc the world?s leader in exploration and development of deep ocean mineral resources is today focused on the recovery of high grade copper-gold from in seafloor massive sulphide mineralization. These mineralized belts, analogous to land based volcanogenic massive sulphides (VMS) deposits are located near tectonic plate boundaries of the Western Pacific and around the world. Nautilus; first development project is Solwara 1 located in benign waters in Papua New Guinea. Since 2006 the company has completed detailed environmental and geological studies at Solwara 1, culminating in a number of world firsts, including the first Environmental Permit for a deep ocean mineral project and the first NI 43-101 compliant seafloor massive sulphide resource statement. Nautilus has relied heavily on proven deepwater technologies from the oil and gas industry in the design of the first mineral extraction system. Pipeline trenching units, workclass ROVs, deepwater production risers and drill cutting removal systems will all be adapted at Solwara 1. Key contractors to the project have all been selected for their deepwater experience, creativity and determination to launch this new industry. Innovation is at the forefront of Nautilus? success to date. This paper gives an overview of the Solwara 1 development and describes the exploration and production technologies adapted for seafloor mineral extraction.

May 1, 2010

By F. W. Gray

A GEOLOGICAL study seeking to determine, for economic purposes, the value of the Sydney coalfield as a source of coal supply. Limitations of the coalfield come under two main heads: (a) Areal extent of the undersea coalfield. (b) The distance from shore at which coal can be mined at a cost of production permitting its profitable sale. Conclusions reached are that the areal extent of seams below the Phalen seam is of. small economic importance, and that non-persistence of these seams in full thickness and quality in the undersea extension of the coalfield will put an end to profitable mining before any limitations connected with distance from the shore-line become operative. With respect to the Phalen seam, non-persistence or deterioration of the seam will become effective in the western part of the coalfield, and less certainly in the eastern part of the coalfield, before operation of limitations by distance from shore. In the central portion of the coalfield, the seam probably persists in commercially workable thickness and quality to beyond the limit of mining set by distance from the shore-line. With respect to the seams above the Phalen seam between the Mountain fault on the extreme western boundary of the coalfield and the assumed termination of the deposition area on the eastern extremity of the field near South Head of Morien, there appear to be only such limitations as arise from engineering approach, distance from shore, sufficiency of strata cover between the sea-floor and the upper coal seams, and quality of the coal (with certain reservations as to the continuity of the upper seams under Sydney harbour and in the Sydney Mines-Little Bras d'Or district). Some of these seams have fragmentary land outcroppings from which their persistence seaward is assumed, and there may be other and still higher seams in the strata column which are entirely submarine.

Jan 1, 1941

By T. P. Weldum, W. Conger

"These studies address the relationship between mill media sizing and its grinding efficiency. Starting with the results from a review of the literature, the issues of initial media sizing for a new ball milling circuit, and then optimal media sizing for an existing milling operation, were studied. The Functional Performance parameters “Mill Grinding Efficiency” and cumulative “Mill Grinding Rates” from both plant and test-scale equipment were used, and provide valuable new insight into this topic. A plant media sizing diagnostic tool is presented, as are newly developed testing equipment and evaluation methods, and recent case studies.REVIEW OF MEDIA SIZING LITERATURE For a plant metallurgist to answer the question “How can I maximize plant profit by manipulating this grinding circuit variable?” she must know what effect the variable has on grinding circuit efficiency. Despite the significant cost of grinding media and its potential effect on production capacity, the ‘best’ media sizing remains ill-defined for any given ball mill circuit in the industry today. The underlying reasons for this will be discussed. But the importance of this issue drove Metcom and its industrial partners to take on the challenge of how to engineer the ball charge for an existing grinding circuit. In the absence of any proven method, the first step was a review of the literature. Sponsored by Cleveland-Cliffs, Inc., a broad review of the literature was undertaken, producing “The Effect of Media Sizing on Ball Milling Efficiency” (McIvor, 1997). Among hundreds of publications that were reviewed that discuss the topics of media sizing or wear, forty-five were studied in detail. These were grouped into: plant experiences; laboratory and pilot plant investigations; media wear studies; population balance modeling studies; and general papers on ball milling which included the topic of media sizing. The reader is encouraged to refer to that review. The findings remain unchanged, although some relevant papers have been written since (e.g. Staples et al, 1997; Banasi et al, 1999; Orford et al, 2006; LaMarsh, 2015). The main findings of the review were as follows:"

Jan 1, 2018

By Fathi Habashi

Poland has a unique copper industry. Copper sulphide concentrates are smelted in six shaft furnaces to produce matte and in a flash furnace directly to blister copper. Anodic slimes from electrorefining are treated by a modern technology to recover the precious metals. INTRODUCTION Poland's copper industry began in 1950 when the old and relatively small mines Lena and Konrad, located in Lower Silesia, were drained and recommenced production. In 1957 the industry entered a period of rapid development with the discovery of a rich ore body in the vicinity of Lubin and Polkowice which was the basis for the establishment, in 1961, of the Copper Mining and Smelting Combine (KGHM). In 1991 the Combine was restructured into a state-owned, joint-stock company under the new name of KGHM ?Polska Miedz? (KGHM ?Polish Copper?). It consists of three mines, three smelting and refining plants, and one rolling mill, and produces about 4% of the world?s copper and about 7% of the world?s silver.

May 1, 2001

The influence of joint orientation and joint persistence, on the mechanical behaviour of jointed rock masses under uniaxial compression, has been studied systematically. The joint inclination angle ß was varied from 0° to 90° with an increment of 15°. The joint continuity factor k was taken as 0.2, 0.4, 0.6 and 0.8. The peak strength, Young’s modulus, the complete axial stress-axial strain curves, the cracking process and the characteristic of the fragments, were investigated. It was found that the anisotropic response of the jointed specimens was governed by the micro-mechanism, such as crack initiation, propagation and coalescence, crack opening or closing, and frictional slip of cracks or joints. With the increase of joint continuity factor, the axial stress-axial strain curves change from single-peak to multipeak, the peak strength and Young’s modulus decrease. The specimens with medium joint inclination angle (30°,45° and 60°) has lower energy dissipation and strength due to stepped or shear failure, while specimens with small and large joint inclination angle (0°, 15°, 75° and 90°) has higher energy dissipation and strength due to axial cleavage or crushing failure.

Jan 1, 2015

By Jarrett. K. M.

Nobody has, as yet, made a perfect machine. Therefore, when a machine is operating and functioning as it is designed to do, there is always some vibration present. This is easily and simply measurable with present-day equipment and any increase in the amount of vibration will indicate a potential failure. When an increase is noted, vibration analysis can pinpoint the cause of the potential failure and remedial action can be taken before an unscheduled shutdown is necessary or a breakdown occurs.

Jan 1, 1972

By D. Van Tonder

ABSTRACT The comparative economics of ion exchange and direct precipitation have been analyzed by developing indicative CAPEX/OPEX models for typical alkaline leach uranium circuits. An agitated tank ore leach application is considered, comparing resin-in-pulp and direct precipitation as recovery options. Capital and operating cost estimates are derived from rates and factors used in recent studies and projects. The analysis showed the main economic drivers to be the ore grade and resin loading. The resin loading is impacted by the prevalence of competing ions, especially chloride. At resin-in-pulp solution chloride concentrations below 3 g/L and uranium grade below 640 g/t U3O8, resin-in-pulp is more economical, whereas at chloride concentrations above 3 g/L, direct precipitation is more economical.

Jan 1, 2012