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By R. C. J. Goode

"In my Presidential address last year `The Institute in Retrospect and Prospect', I briefly reviewed the past activities of our Institute, I commented on the dynamic growth of the mineral activity of this country and of the great contribution towards this growth made by members of this Institute. I maintained that there was still further growth to come, pointing out that our future would be very much dependent on the availability and skills of our mining and metallurgical men. This Institute had, therefore, a most important task ahead to ensure that this country would have the necessary skilled engineers to develop our mineral industry so that we would be able to compete successfully in the wide world. In my address I highlighted many of the major achievements of our members and of our Institute. In today's review, I have no wish to repeat myself and I would, therefore, ask members and visitors to regard this review as complementary to my presidential address. I must also refer you to the very full resume of our affairs written for a special brochure in March, 1944, by E. H. Johnson, a founder member, on the occasion of our 50th Anniversary. There is no need to repeat what was given there, rather I will attempt to bring that history up to date. Our Institute was founded under the name of Chemical and Metallurgical Society of South Africa on 24th March, 1894, by a group of chemists and metallurgists The name was changed to Chemical, Metallurgical and Mining Society of South Africa early in 1903, and in July, 1956 became The South African Institute of Mining and Metallurgy. We were not the first technical organisation in South Africa, the S.A. Association of Engineers and Architects having been formed in 1892. In that year also the British Institution of Mining and Metallurgy started in London. A chronological table of some of the more important societies is as follows: British Societies: Society of Apothecaries 1617 Royal Society 1660 Geological Society 1807 Institution of Civil Engineers 1818 Institution of Mechanical Engineers 1847 Institution of Chemistry 1877 Institution of Mining Engineers 1889 Institution of Mining and Metallurgy 1892 Other Societies: Mining Society of Nova Scotia 1887 S.A. Association of Engineers and Architects-later the S.A. Association of Engineers which amalgamated with the Transvaal Institute of Mechanical Engineers 1892 Australasian Institute of Mining and Metallurgy 1893 Geological Society of South Africa 1895 South African Society of Electrical Engineers-disbanded 1904 1897 Mechanical Engineers' Association of the Witwatersrand-later, the

By H. Möller, L. Mashigo, C. Gassmann

Wire-arc additive manufacturing (WAAM) is a directed-energy deposition technology that uses arc welding procedures to produce computer-aided designed parts, such as three-dimensional printed metal components. A challenge of additive manufacturing is the anisotropy. Interstitial elements play a significant role in the mechanical properties of Ti6Al4V of different grades. In this research, the mechanical properties of Grade 5 and Grade 23 Ti6Al4V were compared for this application. Samples were extracted from WAAM-produced Ti6Al4V walls in different directions (horizontal and vertical) and at different positions (top and bottom). The samples were subjected to optical microscopy and tensile and hardness tests. Grade 5 Ti6Al4V samples were found to have greater strength, greater hardness, and lower ductility, owing to the higher content of interstitial elements compared with Grade 23. The bottom samples had higher strength than the top samples, which is attributed to thermal cycling during manufacturing, resulting in different microstructures.

Jul 1, 2021

By A. Tekin

In almost all branches of industry, machinery and equipment in operation cause vibration. Some sources of vibration affect only the operator’s hands, fingers, and arms, while others have adverse effects on the entire -body. Various types and numbers of machines are utilized in the mining sector, and operators with them are exposed to mechanical vibrations caused by the mining machinery they use. A field study was conducted to evaluate the vibration risks to the operators using mining machines in open pit mines. Vibration levels and whole-body vibration (WBV) measurements using various types brands, and models of construction equipment were evaluated in three different mines in the west of Turkey and compared to the the criteria specified in the EU 2002/44/EC directive and ISO 2631-1 (1997) standards. The results showed that operators using mining machinery for 8 hours were exposed to WBV levels below the EU limit (1.15 m/s2), while 44% of these operators were exposed to levels above the EU action limit (0.5 m/s2). Measurement data collected from the working environment and the recommended improvements that need to be made to reduce WBV exposures are presented.

May 2, 2022

By M. Z. Emad, A. Hassan, M. A. Raza, M. U. Khan, S. A. Saki

Digital modelling of a surface is crucial for Earth science and mining applications for many reasons. These days, high-tech digital representations are used to produce a high-fidelity topographic surface in the form of a digital terrain model (DTM). DTMs are created from 2D data-points collected by a variety of techniques such as traditional ground surveying, image processing, LiDAR, radar, and global positioning systems. At the points for which data is not available, the heights need to be interpolated or extrapolated from the points with measured elevations. There are several interpolation/extrapolation techniques available, which may be categorized based on criteria such as area size, accuracy or exactness of the surface, smoothness, continuity, and preciseness. In this paper we examine these DTM production methods and highlight their distinctive characteristics. Real data from a mine site is used, as a case study, to create DTMs using various interpolation techniques in Surfer® software. The significant variation in the resulting DTMs demonstrates that developing a DTM is not straightforward and it is important to choose the method carefully because the outcomes depend on the interpolation techniques used. In mining instances, where volume estimations are based on the produced DTM, this can have a significant impact. For our data-set, the natural neighbour interpolation method made the best predictions (R2 = 0.969, β = 0.98, P < 0.0001).

Feb 6, 2023

To the members of The South African Institute of Mining and Metallurgy I have audited the annual financial statements of The South African Institute of Mining and Metallurgy set out on pages 641 to 644 for the year ended 30 June 2006. These annual financial statements are the responsibility of the Institute?s Council members. My responsibility is to express an opinion on these annual financial statements based on my audit. Scope I conducted my audit in accordance with International Standards on Auditing. Those standards require that I plan and perform the audit to obtain reasonable assurance about whether the annual financial statements are free of material misstatement. An audit includes: ?examining, on a test basis, evidence supporting the amounts and disclosures in the annual financial statements, ?assessing the accounting policies used and significant estimates made by management, and ?evaluating the overall financial statement presentation. I believe that my audit provides a reasonable basis for my opinion. Audit opinion In my opinion, the annual financial statements present fairly, in all material respects, the financial position of the Institute at 30 June 2006 and the results of its operations and cash flows for the year then ended in accordance with generally accepted accounting practice appropriate to the Institute. Supplementary information The supplementary schedule does not form part of the annual financial statements and is presented as additional information. I have not audited this schedule and accordingly do not express an opinion on it.

Jan 1, 2006

By J. Sehata, J. Tshilongo, I. Govender, S. Pikinini, T. L. Moodley, M. Raedani

In the face of dwindling Merensky ore reserves in the early 1990s, Mintek developed the MF2 flotation circuit to economically recover platinum group metals from the shallow upper group-2 chromitite reef. By aligning the primary and secondary grind to the platinum group metal liberation kinetics, excessive fine chromite generation was avoided, and thus one could consistently produce high-grade concentrates (>200 g/t platinum group metals) with low chrome content (<3% Cr2O₃), well within smelter tolerances. This, coupled with upper group- 2's low-cost open-pit mining, made it particularly attractive to investors and mining houses alike. As a result, deeper lying reefs like middle group and lower group with lower platinum group metals grades and complex mineralogy, were primarily mined only for chromite using density-based separation processes (like spirals), of which the waste tailings are best classified as secondary platinum group metals resources. Today, with global platinum group metal demand rising and high grade upper ground-2 reserves rapidly diminishing, the industry must revisit these middle group and lower group tailings. Mineralogical analysis reveals several challenges: Middle group tailings feature platinum group metals locked within silicate matrices, while lower group tailings contain fine chromitite fragments, and are hosted within non-floating laurite grains, each presenting liberation and gangue issues. Smelter constraints still demand concentrates below 3% Cr₂O₃, requiring solutions that consider both platinum group metals recovery and chrome entrainment. To develop a solution, two lower group chrome spiral tailings samples were obtained from a large chrome mine: Sample A (+425 μm – 106 μm) and Sample B (−106 μm). Initial assays showed Sample B contained higher platinum group metal grades but also higher Cr₂O₃. As such, different blends of flotation feeds were evaluated using ratios of 90:10 (C1) and 80:20 (C2) of Sample A to Sample B, targeting the coarse fraction's lower chrome content while recovering valuable platinum group metals from the fines. This work proposes a practical route for mining houses to unlock additional platinum group metal value from lower group ore spiral tailings. By optimising blending ratios and reagent suites, it is possible to meet smelter chrome and platinum group metal grade thresholds, whilst still obtaining economically viable PGM recoveries.

Mar 6, 2026

1. New books Extractionmetallurgy&apos;81. London, Institution of Mining and Metallurgy, 1981. 441 pp. $40. Structures and properties of engineering alloys, by W. F. Smith. London, McGraw-Hill, 1981. 512 pp. R89,65. Rock and mineral analysis, by W. M. Johnson and J. A. Maxwell (editors). 2nd ed. New York, Wiley, 1981. 424 pp. $40. Mining methods and equipment, by Mining Information Services. London, McGraw-Hill, 1981. 218 pp. International directory of acronyms in library, information and computer sciences, by P. M. Vaillancourt. New York, Bowker Publishing Co., 1980.516 pp. 2. New journals Trends in analytical chemistry (TRAC), Amsterdam, Elsevier, 12 issues per year. Subs. for Volume I (16 issues) D.H 95.50. Engineering management international, Amsterdam, Elsevier, 4 issues per year. V.S. $32.50, D.H. 70.00. 3. Mineral policy sector publications Mineral Bulletin MR 188. Vanadium: an imported mineral commodity. $3.60. Mineral Bulletin MR 190. Canadian mines: 1980 perspective. $3.00. Canadian mineral survey 1980, by the staff of Mineral Policy and Energy Sectors. $1.00. 4. NIM reports Report 2090 Observations made during the dig-out of a 48 MV A ferrochromium furnace. Report 2110 The investigation of a fracture on one side of a skip bridle in a mine shaft. Report 2111 Pilot-plant tests for the recovery of chromite and the noble metals from the UG-2 Reef at Maandagshoek. Report 2112 The behaviour of UG-2 chromite concentrates during smeUing. Report 2113 M uUivariable control of a milling circuit at East Driefontein Gold Mine. Report 2115 Estimation of material variation in powdered materials Report 2116 Optimum operation of a direct-reading spectrometer with excitation by a 5 kW inductively coupled plasma torch. Report 2121 Five robust indicators of central value. Report 2124 The direct determination, by differential pulse anodicstripping voUammetry at the thin mercury-film electrode,of cadmium, lead, and copper. Report 2127 The preparation of a reference material of South African zirconium concentrate from Richards Bay. Report 2128 The determination, by differential pulse anodic-stripping voltammetry at the thin mercury-film electrode, of cadmium and thallium in six NIMROC reference materials Report 2130 The organizing of conferences. Research grant The Board of Directors of International Precious Metals Institute in conjunction with Gemini Industries, Inc., a California-based refiner of precious metals, recently announced a Gemini Research Grant of $3000 will be awarded annually to a graduate student who is pursuing studies in metallurgy, chemical processes as it pertains to precious metals, or materials sciences, and who is performing or planning research studies in the precious metals. Accidents and diseases The Third International Colloquium for the Prevention of Occupational Accidents and Diseases in the Iron and Metal Industry is to be held on 15th and 16th June, 1982, in Palma de Mallorca, Spain.

Jan 1, 1981

By M. Splaine, W. Davison, D. C. Atkinson

"Since 1964, Nchanga Consolidated Copper Mines, Ltd., has been developing and using production scheduling methods for optimizing its metallurgical operations in the short term (up to one year). Medium-range metallurgical planning has been possible only by successive evaluations of a single-year L.P. A modified version of Rosenbrock&apos;s direct search technique has now been developed to allow multi-year optimization of both mining and metallurgy for medium-range planning. The modifications to the search technique have produced a marked increase in computational efffciency for this heavily constrained problem in many variables and the system is a usable planning tool, given a reasonably powerful computer. The plans are &apos;optimum&apos; in the sense that they yield the maximum present value of the operations.Each of the resulting five-yearly mine plans forms the basis for further detailed metallurgical evaluation by the established production scheduling system."

Jan 1, 2014

By L. Cong, C. Liu, N. Zhang, W. Cao, C. Zhou, X. Fan

"The modes of occurrence of arsenic and the effects of low-intensity leaching-flotation on arsenic removal from coal slime from the Tanggongta Plant, Inner Mongolia, China were investigated. The coal slime was examined using hydride generation inductively coupled plasma optical emission spectrometry and X-ray diffraction to obtain the content of elements and the major minerals. The modes of occurrence of arsenic in minerals were determined using selective leaching, float-and-sink analysis, and polarized light microscopy. The results indicate that pyrite is the dominant carrier of arsenic in the coal slime, which predominantly exists in association with clay. Significant proportion of the arsenic is removed by a low-intensity leaching-flotation process, consistent with the data from selective leaching and flotation of gangue. The results show that low intensity leaching-alkali washing-flotation is more efficient than direct flotation and low-intensity leaching-flotation.IntroductionUnderstanding the occurrence of arsenic in coal and its removal is significant in optimizing coal utilization, because arsenic in the environment is viewed as a potentially toxic trace element (Finkelman, Belkin, and Zhang, 1999; Hall, 2002; Smith et al., 1992; Smedley et al., 2003; Zheng et al., 1999). Many studies on the modes of occurrence and concentration trends of arsenic in different coal and washing products have been performed (Diehl, Goldhaber, and Hatch, 2004; Kolker et al., 2000; Quick and Irons, 2002; Wang et al., 2006; Fan et al., 2016). Trace elements are usually preferentially associated with certain minerals and the form that these minerals take will influence the efficiency of removal during cleaning (Quick and Irons, 2002). Arsenic is mainly associated with minerals such as pyrite, carbonate, and silicate (Demir et al., 1998; Diehl, Goldhaber, and Hatch, 2004; Zhou et al., 2014). The existence of organically bound arsenic was also confirmed using X-ray absorption (Kolker et al., 2000). However, inorganic arsenic is the principal source of pollution because of its leachability and high concentration compared with organic arsenic (Fujino et al., 2004; Gao, Lu, and Wang, 2010; Jiang et al., 2008; Kolker et al., 2000)."

Jan 1, 2017

By N. Wagner, P. den Hoed, J. D. Steenkamp, S. Soqinase

In pyrometallurgical processes, metal oxides are reduced from molten slag through carbothermic reduction. It is of interest to evaluate the reactivity of the carbonaceous materials towards substances such as slag. Characterization techniques such as coal petrography can provide insight into the influence of feed coal properties and how they potentially dictate reductant performance. This study aimed to compare the petrographically determined organic composition of coal to reductant reactivity. Two South African medium-rank C bituminous coals and one anthracite sample were investigated together with high-carbon ferromanganese industrial slag. The reductant reactivity tests were conducted at 1500°C in a muffle furnace to assess the potential of carbonaceous reductant in reacting with the main slag components. SEM-EDS was applied to understand the extent of MnO (and to a lesser extent, SiO2) reduction from the slag. Coal 2, consisting of a greater proportion of vitrinite (59.5 vol% on a mineral matter-free basis and 54.7 vol% including mineral matter) was the most reactive reductant. The anthracite sample, with the highest inert maceral proportions (71.8 vol% including mineral matter and 76.8 vol% on a mineral matter-free basis), was the least reactive reductant.

Feb 6, 2023

By M. A. Mahboob, T. Celik, B. Genc, I. Atif, S. Ali

"Mapping of hydrothermally altered areas, which are usually associated with mineralization, is essential in mineral exploration. In this research, open source reflectance spectroscopy data from the multispectral moderate-resolution Landsat 8 satellite was used to map altered rocks in the Gauteng and Mpumalanga provinces of South Africa. The unique spectral reflectance and absorption characteristics of remotely sensed Landsat data in the visible, near-infrared (NIR), shortwave-infrared (SWIR) and thermal infrared (TIR) regions of the electromagnetic spectrum were used in different digital image processing techniques. The band ratios (red/blue, SWIR 2/NIR, SWIR 1/NIR), spectral band combinations (Kaufmann ratio, Sabins ratio) and principal component analysis (Crosta technique) were applied to efficiently and successfully map hydrothermal alteration minerals. The results showed that the combination of spectral bands and the principal component analysis method is effective in delineating mineral alteration through remotely sensed satellite data. The validation of results by using the published mineral maps of the Council for Geoscience South Africa showed a good relationship with the identified zones of mineralization. The methodology developed in this study is cost-effective and time-saving, and can be applied to inaccessible and/or new areas with limited ground-based knowledge to obtain reliable and up-to-date mineral information.IntroductionMany developing nations depend on exploration and exploitation of mineral resources to sustain their economic growth. Usually, the traditional mineral exploration techniques require enormous finances, prolonged time, and tremendous manpower, particularly in areas that are not easily reachable (Maduaka, 2014). Furthermore, mineral exploration required state-of-the-art techniques and expertise along with geological, geochemical, and geophysical datasets, which may not be easily available or may be lacking where access is problematic (Kaiser et al., 2002; Bemis et al., 2014). Modern remote sensing technology has proved to be one of the highly efficient and robust techniques used for mineral exploration. The use of remote sensing satellite images for geological mapping and mineral exploration usually involves studying the physicochemical properties of rocks and weathering soils, such as mineralogy, landforms, geochemical signatures, and the spatiall distribution of lineaments (Bhattacharya et al., 2012)."

Mar 1, 2019

By F. H. Deist, M. P. Roberts

"The Collieries Research Laboratory of the Chamber of Mines of South Africa is developing a coherent system of programs to aid in the full spectrum of activities arising in the planning of new as well as operating mining enterprises. It is the purpose of this paper to describe the design and application of two subsystems in the complex.One of these subsystems is an initial version of a production simulator. This program draws upon a model of a mining enterprise and simulates the operational and financial aspects of a set of alternative mine production plans.These plans are specified in terms of proposed sequences of operations. Details such as reserves, production rates, resource requirements and so on, are taken from the model.Physically, the model takes the form of a cross-referenced data base, maintained by means of a general file maintenance system which is another subsystem described.The paper concludes with a description and analysis of the first practical application of the two programs."

Jan 1, 2014

1. Book review The geology of some northern Nigerian anorogenic ring complexes, by J.N. Bennet, D.C. Turner, E.C. Ike, and P. Bowden. The British Geological Survey: Overseas Geology and Mineral Resources, no. 61. London, HMSO, 1984. 66 pp. Reviewer: R.H. Ingram 2. Mintek reports Report M226 The separation of tungsten and molybdenum by the formation of sulphide complexes and extraction into a weak-base resin. Report M228 The solvent extraction of zinc, iron, and indium from chloride solutions by neutral organophosphorus compounds. Report M230 Shear flocculation of fines for improved flotation. Report M239 A mineralogical study of residue from the column leaching of a low-grade nickel-copper sulphide ore.3. Recent publication Driger Review, special edition, act. 1985. 48 pp. (Copies obtainable from Roly Nyman, HAMPO PMIE Division, P.O. Box 170, Joham1esburg 2000.) Black Mountain&apos;s achievement The 13 689 t consignment of metal concentrate that was loaded aboard the bulk carrier &apos;George&apos; and shipped out of Saldanha Bay early in December brought the number of tons exported from Black Mountain via the Sishen-Saldanha railway and harbour system to one million.

Jan 1, 1986

By R. P. King

"A model of the flotation process can be used effectively for design and control. For design purposes it can be used to predict the performance of a large plant from laboratory and pilot plant data. It can be used for control purposes to assess the utility of any proposed operating modification to an existing plant, and it can also be used to determine optimal control settings for best operating performance.A model has been developed that will allow for variations in feed properties and for variations in fineness of grind. The model can be used to assess the effects of reagent addition rate, aeration rate and pulp level on plant performance and these are the control variables that are used individually or together in all operating flotation plants. The model provides for a distribution in the values for flotation rate constants, particle size and mineral fraction, and, because of its complexity, requires a large computer when it is to be applied to a typical plant configuration. The computational method that is used to apply this model to such configurations is described in this paper, and particular attention is paid to the problem of allowing for feedback of tailings from cleaners and recleaners."

Jan 1, 2014

Notices TRANSPORTATION AND THE ENVIRO NMENT The 5th Quinquennial Convention of the S.A. Institution of Civil Engineers will take place at the Carlton Centre, Johannesburg, from 20th to 24th August, 1973. ENVIRONMENTAL ENGINEERING A conference on environmental engineering problems in industrialized and developing countries is to be held at the United Engineering Centre, New York, on 19th and 20th September, 1973. RABCEWICZ-COLLOQUY The Austrian Society for Geomechanics is to honour Professor Ladislaus V. Rabcewicz, on the occasion of his 80th birthday, with a meeting in Salzburg Congress Hall on 11th and 12th October, 1973. The themes of the four half-day sessions will be as follows. PYRO MET ALL URG ICAL EVENTS IN 1974 Diisseldorf is to be the venue for the following three events: International Iron and Steel Congress O.F.S. Branch Welkom THE MARCH GENERAL MEETING OF THE BRANCH WAS HELD IN THE ST. HELENA CLUB AT 8.00 P.M. ON TUESDAY, 6TH MARCH, 1973 O.F.S. Branch Welkom MINUTES OF A GENERAL MEETING HELD IN THE ST. HELENA CLUB ON WEDNESDAY, 16TH MAY, 1973, AT 8.00 P.M.

By O. Korhonen, T. Leskinen

The use of large OK-16 flotation machines at the concentrators of Outokumpu Oy by o. KORHONEN and T. LESKINEN(Visitors) The development ofthe OK-16 flotation machine is described briefly, and an account is given of its use at various concentration plants in Finland. The benefits arising from the use of larger flotation machines are listed, and the technical specification of the OK-16 machine is detailed in an appendix.

Jan 6, 1976

By A. M. Venter, C. W. Siyasiya, N. K. K. Arthur, M. G. Willemse, D. Marais

Although additive manufacturing is fast gaining traction in the industrial world as a reputable manufacturing technique to complement traditional mechanical machining, it still has problems such as porosity and residual stresses in components that give rise to cracking, distortion, and delamination, which are important issues to resolve in structural load-bearing applications. This research project focused on the characterization of the evolution of residual stresses in Ti-6Al-4V extra-low interstitial (ELI) additive-manufactured test samples. Four square thin-walled tubular samples were deposited on the same baseplate, using the direct energy deposition laser printing process, to different build heights. The residual stresses were analysed in the as-printed condition by the neutron diffraction technique and correlated to qualitative predictions obtained using the ANSYS software suite. Good qualitative agreement between the stress measurements and predictions were observed. Both approaches revealed the existence of large tensile stresses along the laser track direction at the sections that were built last, i.e., centre of the top layers of the samples. This in addition leads to large tensile stresses at the outer edges (corners) which would have the effect of separating the samples from the baseplate should the stresses exceed the yield strength of the material. Such extreme conditions did not occur in this study, but the stresses did lead to significant distortion of the baseplate. In general, the microstructures and spatial elemental mapping revealed a strong correlation between the macro-segregation of elemental V and the distribution of the β-phase in the printed parts.

Feb 6, 2023

By M. G. Atmoret

It seems to me to be particularly appropriate that this topic should be discussed at the first prize-giving function of this kind. As you know, this presentation of awards to young mining engineers and metallurgists is to be an annual event, and never before in the dynamic and rapidly changing climate of the South African metallurgical industry has it been more necessary for young, and perhaps older, practitioners to consider the future of their profession and their role in the industry. I look forward with interest to the time, five to ten years from now, when I shall recall my crystal-gazing of tonight to see how far wrong I have been.

Jan 1, 1977

By R. C. Urquhart, W. P. Channon, D. D. Howat

Discussion: The mode of current transfer between electrode and slag in the submBerged-arc furnace by w. P. CHANNON, R. C. URQUHART, and D. D. HOWAT J. MEINTJES I have read the paper with much interest, and I should like to make a few observations. (I) The experimental work deals with resistance heating by an electrode immersed in a slag... AUTHORS&apos; REPLY We thank Mr Meintjes for his critical analysis and helpful comments arising out of his study of our paper. Possibly we should emphasize at the outset that our experiments all related to the conditions in which the lower portion of the electrode was immersed in molten slag. We believe, however,

Jan 12, 1974

By L. Aspola

The platinum group metals (PGMs), i.e. ruthenium, rhodium, palladium, osmium, iridium, and platinum, are typically found in association with each other, but also importantly, with nickel and copper. Typically Platinum and palladium have the greatest economic significance and other PGMs are typically produced as co-products of these. With recent increases in the value of nickel, cobalt, and the PGMs and an ever increasing focus on the sustainable use of metals, interest in the processing of secondary feed material sources and metal-bearing residues has also substantially increased. As an efficient, proven, and environmentally sound technology Outotec Ausmelt Top Submerged Lance (TSL) Technology has gained commercial acceptance in the nickel industry, including PGM recovery. For the processing of nickel- and PGM-bearing feed materials, five Outotec Ausmelt Furnaces at four sites are in operation. Two of these furnaces are located in Rustenburg, South Africa, which is by far the biggest mine-based producer of platinum. Outotec also has hydrometallurgical processes available for further treatment and extraction of PGMs, which are also briefly discussed.

Jan 1, 2012