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By P A. Collier

The general view of the author is that all the good intentions of manufacturers can fail completely if the variations in circumstances in underground mining are not considered at all times. With a belief that it is the customer that has the experience and know ledge of problems which occur on long installations. Reilloc talk with customers in coal mines around the world, and have done so from their inception. With considerable experience in their home market, their technical approach was received with enthusiasm by coal companies in both Australia and South Africa, and whilst experience was obtained in other countries, it is the particularly close working relationship in these two areas that is covered in this paper. The refinement of manufacturing techniques and the fine tuning of the specification to which the chain is made was developed in conjunction with factual underground experience obtained by customers as they sought to improve their productivity and a reduction in working costs. With a reliable product the mines are able to concentrate on improved operational techniques to extend the useful working life and plan for multi-panel usage of the chain.

Jan 5, 1996

By Z. Sawlowicz

Finely dispersed, primary sulphide mineralisation in the Cu-Fe sulphide zones of copper-bearing shale of the Polish part of the Permian Kupferschiefer is mainly present in the form of framboids and spherules. This type of mineralisation is especially well preserved in organic-rich shale, where it often dominates over a later diagenetic mineralisation that consists of large grains and veins. In microscopic observations special attention was paid to composite grains of copper and iron sulphides. The results suggest that the Cu-Fe and Cu sulphides precipitated in the Kupferschiefer sediment before pyritisation of the framboids had ceased and that they replaced metastable precursors of pyrite. The precipitation of copper sulphides could have been delayed owing to the formation of Cu-organic complexes.

Jan 4, 1992

By A. A. R. Gomes, X. Leca

Strong disagreement is registered by A.A. Rocha Gomes with Leca's account of the discovery published in Trans. IMM B, vol.99, 1990, p.B139-B152, which he contends minimises the role of the Portuguese state organisation Servico de Fomento Mineriro (SFM); the author, in response, once again thanks all SFM staff but reiterates his conclusion that Neves-Corvo was discovered through an amalgamation of exploration results and interpretations from different sub-disciplines and geoscientists

Jun 13, 1905

For the convenience of those who are unfamilar with thermodynamics, the following brief description and explanation is given of the thermodynamical terms and methods used in this book. It must, however, be strongly emphasized that the account given below is not an introduction to chemical thermodynamics; its sole purpose is to give the reader a rough understanding of the methods used in the earlier chapters. For further information, reference must be made to the standard textbooks on chemical thermodynamics by Glasstone.

Jan 1, 1953

"Prior to the publication of the General Report of the Miners' Phthisis Prevention Committee of South Africa in 1916 little attention was paid to the dust hazard and the necessity for its suppression in the underground workings of the Broken Hill mines. Such precautions as were observed for the elimination of dust were related rather to the prevention of lead poisoning, which, in the early days of Broken Hill when large tonnages of lead carbonate ore were being won, was rather prevalent. Ventilation and hygiene followed the general practice in this and most foreign countries.This paper covers incidence and action since 1918, considering medical aspects and operating aspects. "

Jan 1, 1947

By S. K. Chaulya, R. S. Singh, B. B. Dhar

Two prominent local species, Dendrocalmus strictus (bamboo) and Saccharum spontaneum (kashi), and two exotic species, Cymbopogon citratus (lemon grass) and Vetiveria zizanoides (vetiver), were selected for growth trials on dumps at Mandaman, Chora, Mudidih, South Balanda and Ghugus. The climate at these sites is dry tropical and the surface soil layer a slightly acid to neutral sandy to clayey loam 10-11 cm thick, impoverished in major plant nutrients. After two years bamboo had grown the most, up to 325 cm in height, and contributed the greatest biomass, 638 g/m2 of plant. The local kashi species had a very good regenerative capacity, which was lacking in the lemon grass and vetiver. The grasses had very good soil-binding capacity and could also provide income if used as cash crops

Jun 21, 1905

By Evans E. C.

Discussion of the paper presented at the Manchester Geological and Mining Society' general meeting held in Manchester, March 14th , 1916, with Leonard R. Fletcher, President, in the Chair included contributions by Fletcher L.R., Paton J.D., Orchard A.J.A., Ross A., Gerrard J. and Stephenson H., with the author's responses

Dec 1, 1916

By G. G. Lambert

The paper traces the pattern of spontaneous combustion in the workings of what was originally Hemsworth Colliery, but since July 1967 is now part of South Kirby Colliery. Examination is made of the Barnsley Seam sections and the part played by the top section of the seam as it comes in close proximity to the main seam. In this area of the colliery nine mechanised faces were set away between the years 1953 and 1968, every one "fired" at the pillar edge and six "fired" at the face line when production had ceased. The paper deals with the different preventative measures used, from sandbag walls, cement injections, spraying with polyurethane, until finally using Mandoseal as a sealant. Since the latter method was first used, the last three faces worked in this particular area were all salvaged completely, without any sign of a heating developing.

May 23, 1905

By NA NA

Background information on Exchem Mining and Construction and its products.

Jan 7, 1997

Discussion of papers with authors' written replies and closing remarks.

Jan 1, 1947

By M. J. Russell, W. E. Stephens, D. B. Mohamad, A. B. MacKenzie

Redox front processes in rocks are important in the context of both radioactive waste disposal and the development of orebodies. Results are presented from a study of the distribution of uranium and thorium and the natural decay series equilibrium about redox fronts in a granite at the Criffel pluton and Craignair quarry, Dalbeattie in southwest Scotland. The results are considered in the context of large scale uranium aqueous transport in the region and compared with those from a previous study of highly developed redox fronts at Pocos de Caldas, Brazil. Results show that the Criffel pluton has experienced a recent and rapid removal of uranium from the uppermost section of the granite whereas thorium has remained relatively immobile. The radium and uranium distributions indicate that diffusion processes probably control the distribution of radionuclides about the front. These processes are similar to those observed at Pocos de Caldas. The trends of concentration and activity ratio about the Dalbeattie redox front are less pronounced than those at Pocos de Caldas owing to the shorter time available for the process and the lower intensity of weathering at Dalbeattie.

Jan 12, 1992

By M. Rahman, P. C. Kapur

The fixed-time locked-cycle grinding test is employed to simulate the industrial closed grinding circuit on the laboratory scale. A mathematical algorithm for 'cyclewise' computer simulation of the locked-cycle test has been derived and used to study an idealised laboratory-scale model of a closed ball-mill circuit. The agreement between simulated and experimental results is reasonably good, except when the grinding times are relatively long

Dec 1, 1971

By A. C. Dunham, Y. D. Drakapoulos, P. W. Scott

The Pt and Pd occur alloyed with copper in small, irregularly-shaped grains, 0.25-5.0 micrometers in maximum dimensions. Grains of unalloyed native copper are also present. The grains are completely surrounded by or marginal to magnetite with inclusions of Ni-Fe-Co sulphides and native Ni-Fe, which is apparently a product of the serpentinisation process. Crystallisation of the Pt-Pd-enriched copper probably occurred at the same time, at low temperature, but the previous form of the Pt and Pd is unknown as no earlier PGE phases have been found. While Pt and Pd minerals are usually important in early-magmatic base-metal sulphides, Pt alloyed with Cu is extremely rare and apparently occurs only very late in the paragenetic sequence. A Cu alloy with Pd dominant over Pt and only minor amounts of other elements appears not to have been reported

Jun 14, 1905

By P. K. Kaiser, R. K. Brummer

Paper presented at the conference Risk assessment in the extractive industries, held in Exeter, 23-24 March 1994. A risk-based decision-making procedure has been developed for selecting rockburst-resistant tunnel support in burst-prone mines. The method is based on a risk-cost-benefit analysis and uses support cost data, costs associated with the risk of support failure or excavation loss, costs associated with accidents, injuries and deaths, and the benefits achieved by installing rockburst-resistant support. It takes into account the risk of damage to the support systems due to rockbursts, potential loss of production and the need to rehabilitate in the event of a damaging rockburst. A practical example is provided to illustrate the principles involved in the decision process

Jun 17, 1905

By I. Garba

The Bin Yauri deposit in the Zuru schist belt of northwestern Nigeria is a vein-type quartz-sulphide-carbonate gold mineralisation hosted by a brittle fault zone. The occurrence of the mineralisation in a contact zone of a Pan-African granitoid was believed to be sufficient evidence of deposition from magmatic fluids. However, studies may now indicate a metamorphic source for the mineralising fluids. A study of rare earth element geochemsitry was used to investigate the nature of the fluid-rock processes involved and identify the sources of the auriferous mineralising fluids.

Jan 12, 1992

By G. Richards

Following on from the article in Materials World February 2015 (Asset 997) this article is the second half of a special focus on graphite. It looks at graphite's market prospects over the next few years. Natural graphite is used in refractories, which accounts for ca. 20% of global demand and is forecast to grow by 2-4%/a to 2020, while the largest growth in demand (increases of 10-15%/a) is estimated to come from its application in anodes for lithium-ion batteries, especially those in hybrid electric vehicles. High-grade natural graphite deposits that are either coming back on stream or are in the pipeline are discussed including Woxna mine in Sweden, Bissett Creek project in Ontario, Canada, Balama mine in Mozambique and Lac Knife project in Quebec, Canada

Mar 1, 2015

By R. E. T. Hill

"A laboratory study was undertaken to determine the condensed equilibrium phase relations at 600°C in that portion of the quaternary Fe-Ni-Cu-S system which lies in the neighbourhood of the monosulphide solid solution (MSS). The study sought to determine to w hat extent copper affects the temperatures of stability and compositions of iron-nickel sulphides in bulk compositions similar to those of massive Fe-Ni-Cu ores. Experimental data, including stable phase assemblages and phase compositions, are presented.In the quaternary system at 600°C MSS forms stable phase assemblages with pentlandite, chalcopyrite solid solution, pyrite and vaesite. Over the range of bulk compositions displayed by natural ores copper as well as metal/sulphur ratio have a significant effect on the thermal stability of pyrite and pentlandite. Errors therefore accompany the widespread practice of ignoring copper or chalcopyrite when the mineralogical and compositional changes that have accompanied the initial cooling of primary magmatic sulphides or their subsequent homogenization during isochemical metamorphism are being deciphered. These errors are most significant for ores the bulk compositions of which lie tow ard the sulphur-deficient side of the cupriferous MSS. Temperatures as much as 300°C above the copper-absent value are possible for the interpreted upper stability limits of pentlandite in these ores.The experimental data show that up to 2.0 at% copper can occur in pentlandite stable at 600°C in a bulk composition equivalent to natural magmatic ores. This is equivalent to nearly 10 vol% chalcopyrite. Pentlandite contains more copper than coexisting MSS and the copper content of both phases increases with increasing iron."

Jan 1, 1984

By D. J. Allan, W. R. Wilson

For conventional aerospace aluminium alloys of the 2000 (copper) and 7000 (zinc, magnesium) series the recycling of process scrap from both metal suppliers and aircraft manufacturers is a well-established, worldwide industry. The recent introduction of a new family of alloys that incorporates lithium has posed a new challenge to the recycling industry owing to the high cost of lithium, its high reactivity to the atmosphere and to refractories and its absence from the specifications of all other registered alloys. Various process options for recycling have been identified, but vacuum distillation has been selected as the most cost-effective and technically feasible solution. Experimental work established that the separation of Li from AI-Li scrap is feasible and an industrial process has been designed. The economics of Li recovery are very sensitive to the AI-Li content of the feed material. Owing to the design of aerospace vehicle manufacturing plants it is expected that the swarf will be mixed with other alloys. A method of enriching this feed has been developed that is based on the control of swarf morphology by thermal and mechanical treatments as a precursor to eddy-current separation. After eddy-current separation and vacuum distillation small proportions of Li are retained in the AI residue. The effects of this on the properties of conventional AI-Si shape-casting alloys were investigated and safe threshold levels have been established.

Jan 4, 1993

Jan 1, 1984

By NA NA

Reports of discussion at sessions held in Keyworth, UK, on 22-23 April 1992.

Jan 12, 1992