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By H. M. Friede

A short survey is given of the Iron Age smelting sites and smelting furnaces that have been found in South Africa. An attempt is made to classify South African smelting furnaces by the inclusion of functional characteristics such as the numbers and positions of tuyeres. An affinity is suggested between the Venda (eastern Transvaal) type of furnace and an East African type. The principles of the smelting process in South African Iron Age furnaces and the characteristics of the smelting products are discussed. Results of metallographic and chemical analyses of 19 iron specimens found at South African sites are given and compared with those from sites in Zimbabwe-Rhodesia, Mocambique, and Nigeria. The carburization and steeling of iron during primitive smelting and forging are discussed.

Jan 1, 1979

By A. Moerman, M. Verreault, V. Falmagne

Noranda has been involved in the development of technologies for automated mining vehicles since 1988, and has contributed in transferring the technological foundation for the suite of SIAM products now being commercialized by STAS. Some of these technologies are now mature and available for commercial implementation in operations where a strong business case can be made for the use of automation. Noranda has successfully implemented or is commissioning the Tele-remote, Auto-loading and truck Guidance technologies at two of its operations, based on operating needs and economic justifications. Operator acceptance, training and maintenance issues have been addressed in order to ensure the reliability and availability of the automation components. These represent the most significant challenges encountered and addressed during the implementation period.

Sep 1, 2001

By J. P. G. Pretorius

The size effect in tests of the compressive strength of coal specimens differs from predictions based on the Weakest Link theory. Predictions of the size effect in tensile tests on lengths of cotton yarn and glass fibre, the behaviour of which is analogous to the weak link process, also differ from observations. This discrepancy is shown to be caused by the correlation between the strengths of the unit lengths in a composite specimen. The Weakest Link theory is reformulated as the Weakness Correlation theory to account for such correlation. It is shown that weakness correlation is found in rock and it is concluded that at least part of the discrepancy between the predicted and observed size effect in rock strength tests could be attributed to this correlation.

By K. R. Vost

"In situ" measurements of the surface heat transfer coefficient in underground airways by K. R. VeST,* B.Se. (Glas.), M.Se. (N.S.W.) (Visitor) Few "in situ" measurements have been made of the surface heat transfer coefficient in mine airways despite the importance of this coefficient in determining the heat flow into the ventilating air. In this paper, the values obtained at various air velocities and the comparisons of these values with theoretical values are given. Examples are also given ofthe errors which would result if rock surface temperatures were obtained by extrapolation from temperatures further into the rock without taking into account the time delay which occurs before a given change in air temperature reaches the points from which extrapolation is carried out.

The Department of Mineral Resources of Thailand is organising, on behalf of the Government of Thailand and the International Tin Council, the Second Technical Conference on Tin. The Conference will be held at Sala Santitham, Bangkok from 18th to 22nd November, 1969. Papers will be grouped under three main headings: (i) Geology and prospecting; (ii) Mining and ore dressing; (iii) Miscellaneous, e.g. stimulating production, metallurgy, estimation of reserves etc. Pre-prints of papers will be circulated. A field trip to Southern Thailand has been arranged for 25th November to 2nd December, 1969. Details of the Conference and the field trip can be obtained from Mr. W. Fox, International Tin Council, Haymarket House, 28 Haymarket, London, S.W.l, England.

By H. White

The applicability of ground penetrating radar (GPR) in numerous qualitative applications has been demonstrated over the past five years in the South African mining industry. These applications include the delineation of faults and dykes, fracture mapping, delineation of shear zones, mapping of depth of weathering, and the delineation of contact between different rock types. The qualitative nature of the data collected using existing commercial GPR systems, often relying on expert interpretation, has however mitigated against the full scale routine application of GPR in the mining industry. The recent development of the RockRadar system by ISS International has, to a large extent, overcome these problems. The result is that quantitative rock-mass studies can now be performed with the RockRadar system.

Jan 1, 1996

By S. Visage

By 1984 Iscor's first direct-reduction plant will be operating at the Vanderbijlpark Works, and for the fin;t time the Corporation will have an alternative method to the blast furnace for producing iron from ore. The performance of Iscor's four-kiln plant, which will be the largest coal-based plant in the world producing sponge iron, will undoubtedly be watched with great interest by steelmakers throughout the world. Beneficiation of tin The Southeast Asia Tin Research and Development (SEATRAD) Centre is a regional oganization, formed by the Governments of Indonesia, Malaysia, and Thailand with assistance from the United Nations, to conduct, coordinate, and promote research and training in the various fields of tin production, including geology, prospecting, mining, mineral processing, and smelting.

Jan 1, 1982

By K. C. Sole

The International Solvent Extraction Conference takes place every three years, under the auspices of the international Solvent Extraction Committee. ISEC '96 held in Melbourne, Australia, in March 1996, was attended by delegates from 34 countries. South Africa was well represented, with delegates from Amplats, De Beers, Mintek, Western Platinum Refinery, and independent consultant Phillip Lloyd (who represents South Africa on the International Committee). The theme of this year's conference was 'Value Adding through Solvent Extraction'. Five plenary lectures were presented. Dr E. Blass of Germany gave the opening presentation entitled 'Solvent extraction-a historical review', which traced evidence for the use of solvent extraction (SX) from the time of the ancient Egyptians, through the Middle Ages and Renaissance, to the Industrial Revolution.

Jan 1, 1996

By T. R. Marrero, J. W. Wilson

The transportation, by water that flows through a pipeline, of coals in the form of water-impermeable cylinders is discussed, and shown to have distinct advantages over other forms of coal transportation, including significantly reduced costs for larger throughputs. The description of the concept comprises various aspects of the system, such as methods for the manufacture of coal logs, their injection into the pipeline, the manner in which they are conveyed in the water in the pipe, and the methods used for their preparation as feed material to electric power stations at the end of the pipeline. It is pointed out that the technology involved in the transportation of coal in the form of logs via pipelines is applicable also to other minerals and commodities.

Jan 1, 1993

By Jean-Claude Paye

In February 1996 the OECD's Environment Policy Committee will commemorate its 25th anniversary with a fifth meeting at Ministerial level. Environment ministers will be taking stock of the progress made by OECD countries in protecting and managing the environment in that quarter-century, and sharing views on likely challenges and co-operative responses. Ministers can point to many important accomplishments. Scientific understanding and technological tools for establishing and monitoring risks to human health and the environment have improved dramatically since the early 1970s. All OECD countries now have in place comprehensive environmental legislation, supported by specialized institutions for policy design, implementation and enforcement. The results of these efforts are increasingly evident in the form of cleaner air and water, and improved protection of natural areas, notwithstanding the many complex problems that remain.

Jan 1, 1996

Robert Rampton Porter died on 8th September, 1985, in Salt Lake City, Utah, at the age of 75. Bob Porter was born in Salt Lake City in 1910, and he attended the University of Utah, where he obtained an M.Sc. degree in metallurgy. Galvanizing In conjunction with the National Institute for Materials Research of the CS I R, the South African Hot-Dip Galvanizers' Association has organized the First International Conference on Galvanizing in South Africa. This event will take place at the C SIR Conference Centre in Pretoria from 3rd to 7th November, 1986. Environmental effects of mining A one-day meeting entitled 'The environmental effects of mining and restoration' will be held on 23rd September, 1986, at the University of Manchester Institute of Science and Technology, Manchester, England.

Jan 1, 1986

By M. B. Algeo

Discussion of the above paper M. B. ALGEO The management and staff of Buffelsfontein Gold Mining Company Limited are to be congratulated on the excellent performances described in the paper presented by Mr Christos. In this day and age, with the current economic and labour situation, the mining industry is being constantly pressed to increase the productivity of ever-diminishing quanta of resources. Stress in rock The ISRM Symposium, 1976 is to be held in Sydney from 9th to 13th August, 1976. It is being organized by The Australian Geo. mechanics Society as a regional symposium of the International Society for Rock Mechanics. Thermal analysis The First European Symposium on Thermal Analysis will be held at the University of Salford on 20th to 24th September, 1976.

Jan 12, 1975

United Kingdom mineral statistics 1977. Home, D., Squirrell, H. C., and Venkatesan, J. (compilers). London, Her Majesty's Stationery Office, 1978. 156 pp. £10,25. Copper mining and management. Navin, Thomas R. University of Arizona Press, Box 3398, Tucson, Arizona 85722. ISBN 0-8165-0586-1. 426 pp. Illustrated. Price Metal statistics 1967-1977. 65th edition. 1978. Metallgesellschaft AG, Reuterweg 14, D 6000 Frankfurt am Main, Fed. Rep. of Germany. 382 pp. Illustrated. Coal mine ground control. Peng, Syd S. John Wiley & Sons. ISBN 0-471-04121-1. 450 pp. Illustrated. £19.75 clothbound. Associate Professor and Chairman of the Uranium supply and demand: Proceedings International Symposium, London, July 1978. Spriggs, Michael J. and Casteel, Kyran D. (editors). Mining Journal Gemorfologiesewoordelys/Geomorpho logical vocabulary. Van der Merwe, J. S., en De Villiers, A. B. (samestellers).

Jan 1, 1979

By H. M. Friede

Iron Age metal working in the Magaliesberg area by H. M. FRIEDE, Ph.D. (Visitor) Evidence of smelting and metal working in the Magaliesberg comes mainly from three sites: Broederstroom (Pretoria District). Uitkomst Cave (Krugersdorp District), and Olifantspoort/Olifantshoek \Rustenburg District). The analyses of copper ores found at or near these sites are reported. as are the analyses of twenty-six samples of slag from the Magaliesberg area and other sites in the Transvaal. Iron implements and copper ornaments found at the Magaliesberg sites are described. and the analyses of some of these specimens are reported and discussed. A metallographic report on two iron objects from Broederstroom points to similarities in the smelting and forging techniques that were practised in the Transvaal and Nigeria during the Early Iron Age.

Jan 6, 1977

By Northrop. I. N.

Hardmetals possess extremely high hardness and wear resistance, which render them ideal for applications such as metal-cutting tools, rock-drilling tools, and industrial wear-resistant parts like dies, punches, and seals. However, hardmetals are britle, and show poor resistance to impact and shock. They can therefore rarely be used unsupported, and it is common practice to attach hard metal working parts to a more resilient tool holder or support, which is normally made of steel. . . . Owing to the widely differing physical and mechanical properties of steels and hard metals, the Joining of one to the other is problematic, and the method used must be chosen with care. This paper reviews several methods available for the joining of hardmetal to steel, and discusses the advantages and disadvantages of each.

Jan 1, 1987

By L. W. Helle

The investigation, which was conducted at Iscor's Newcastle works (in Natal), was aimed at the development of reliable, consistent, and cost-effective methods of sampling. In the sampling of hot metal, it was found that lollipop and spoon samples had identical sulphur analyses, and negligibly different silicon analyses. Thus, spoon sampling of the hot metal was implemented, with a resultant saving of over RIOO 000 per annum on lollipop samplers. In the sampling of steel, aluminium -killed samples were found to have lower phosphorus analyses than titanium killed samples. Spoon sampling was rejected in this application since the use of titanium wire would be too costly. It was decided that titanium would be used as the deoxidant in lollipop samples of steel, and that the Leco carbon! sulphur analyser would be used as the sole arbiter of sulphur content.

Jan 1, 1983

By D. R. Arnold

Discussion of the above paper by D. R. ARNOLDt This paper is the result of an excellent piece of work performed as a service to hyUrometallurgy in general and to the South African uranium industry in particular, and the authors are to be congratulated, Authors' reply Dr Arnold is correct in saying that the present Senbrix resins, which are based on the experimental heavy resins first developed at the National Institute for Metallurgy (NIM), need not necessarily show the same poor performance with respect to cobalt poisoning as the NIM prototypes. Oceanology International The next 01 World Conference is to be held Brighton, England, from 2nd to 7th March, 1980. The programme will concern technical advances in the offshore oil and gas industries, and is expected to include 140 papers from 20 countries.

Jan 1, 1979

By P. A. Laxen, P. J. van Staden

Alternative procedures for the recovery of gold from old sand dumps are discussed, with emphasis on the use of heap leaching. The modification of material to improve its permeability prior to heap leaching is not currently receiving much attention in South Africa. The channeling of solutions through heaps and the high consumption of reagents sometimes ascribed to heap leaching can, as shown by the results described in this paper, be lessened by desliming of the sand prior to heap leaching and the treatment of the resulting slimes fraction by agitation leaching and carbon-in-pulp. This combined procedure results in a higher overal recovery of gold. Alternatively, the sand can be heap-leached as it is after agglomeration with lime and cement, which improves the mixing and neutralization of the material, as well as lessening the probability of channeling.

Jan 1, 1988

1. Journals Quarterly Journal of tke International Tin Research Institute, edited by Colin J. Evans and published by the Institute, Fraser Road, Greenford, Middlesex UB6, 7AQ, England. Engineering, building and construction law review, edited by P. C. Loots and published every two months by Construction Law Review (pty) Ltd (P.O. Box 78020, Sandton 2146, Transvaal), R63,00 per year. 2. Publications of the Mineral Policy Sector Nepkeline syenite and feldspar by B. W. Boyd Potask by G. S. Barry Selenium and tellurium by D. A. Cranstone Sodium sulphate by G. S. Barry Tungsten byG. G. Law-West 3. Mintek reports Report M114 Analytical methods associated with the recovery of uran~um. Report M117 An assessment of tke merits of various types of balls in tke milling of ores. Report MU1 Tke determinatl:on of trace elements in coal by atomic

Jan 1, 1983

1. New books from The Institute of Metals Physical and elastic characterisation, edited by M. McLean. 1989. 228 pp. £25.00.High nitrogen steels, edited by J. Foct and A. Hendry. 1989. 461 pp. £49.50. Proceedings of the First International Calcium Treatment Symposium. 1988. 116 pp. £15.Design for recyc/ability, by Michael E. Henstock. 1988. 150 pp. £15. Solidification processing. 1988. 549 pp. £45.Proceedings of the First International Calcium Treatment Symposium. 1988. 116 pp. £15.Marine engineering with copper-nickel. 1988. 103 pp. £18.Sir Henry Bessemer: An autobiography. 1989.380 pp. £16.95. 2. Other publishers Occupational safety and accident prevention. Behavioural strategies and methods, by C.G. Hoyos and B.M. Zimolong. Amsterdam, Elsevier, 1988. 218 pp. Dfl. 180.00. Algorithms in real algebraic geometry, edited by Denis S. Arnon and Bruno Buchberger. London, Academic Press, 1988. 274 pp. £15.95.

Jan 1, 1989