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The Peko copper orebody is associated with a body of magnetite rock which it has partly replaced. The primary ore averages about 9 per cent. copper and 4 dwt. gold per ton and locally IS much richer. It consists essentially of chalcopyrite and unreplaced magnetite, with lesser amounts of pyrite, marcasite, pyrrhotite, cobaltite, bismuthinite, native bismuth and native gold. The earliest formed mineral is wolfram, and the latest formed is goethite, so that the temperature of deposition ranged from about 5000 C. to 1650 C. or lower.Oxidation extends to 270 ft., which is 100 ft. below the present water level. The oxidized ore consists of cuprite and native copper, and has replaced more or less massive chalcocite of a former zone of secondary sulphide enrichment. The present zone of secondary sulphide enrichment extends from about 270 ft. to 310 ft. depth.INTRODUCTIONThe Peko mine is about 6 miles south-west of Tennant Creek township in the Northern Territory, adjacent to a small outcrop of hematite rock that projects above an otherwise featureless "bull-dust" fiat.The copper-gold orebody being developed in this mine did not outcrop. It was first detected in 1950 by a surface diamond-drill hole (DDH.1), which intersected primary copper ore at a depth of 400 to 425 ft. This ore contained from 4 to 11 per cent. copper and 1 to 25 dwt. gold per ton. Since then a shaft has been sunk, and crosscuts and development drives have been opened on the 210..ft., 300-ft. and 400-ft. levels, which are also connected by winzes. Two diamond drill holes sunk from the 400-ft. level have intersected theorebody at about 450 to 460 ft., and a winze from the 400-ft. level intersected the lode from 445 to 500 ft. At this point it is 54 ft. wide, and averages 9 per cent. copper. More recently an inclined surface drill hole (Peko No. 1) has cut the lode at 856 ft. to 921 ft., equivalent to a vertical depth...

Jan 1, 1955

The objectives of this paper are two-fold. First, it will show what problems can arise when single estimated values are substituted for a distribution of values when evaluating an open pit mine project in the face of uncertainty. Secondly, it will show how the ability to deal with uncertainty and risk in mine project evaluation can have a significant impact on the ownersÆ and stakeholdersÆ investment decision-making. Here a new mine evaluation framework, the integrated valuation/ optimisation framework (named IVOF), is introduced as an alternative tool for mine project evaluation where uncertainty and risk are incorporated in the evaluation process.

Jan 1, 2009

The Greymouth Coalfield contains New Zealand's greatest known resource of bituminous rank coal. The coals are of very high quality, with low ash and sulphur contents and a range of other properties that makes them desirable for a wide range of uses. In fact only a few producers around the world today can offer coals with such exceptional properties. This suggests that Greymouth coal has potential as a premium export trading commodity. These assertions have been largely confirmed by a comprehensive exploration drilling programme funded by Mines Division û Ministry of Energy between 1979 and 1984. The program, forming part of the NZ Coal Resources Survey, was carried out under contract by Lime and Marble Ltd. The drilling of 49 deep, predominantly cored, holes at 1000 m intervals over the coalfield has generated a vast amount of data. It has shown the existence of three major potentially minable coal deposits containing 233 x 106, 33 x 106 and 15 x 106 tonnes of coal in ground. Investigations have at this stage only identified targets and these estimates represent 'in ground' resources, not recoverable reserves. Recent geological studies as well as past and present mining have clearly highlighted the problems posed by the complexity of the coalfield geology. The coalfield lies within a mobile zone in the earth's crust known as the Paporoa Tectonic Zone, which has been active from at least mid-Cretaceous to the present time. Currently this factor poses the greatest obstacle to the determination of mining possibility of the, defined deposit and ultimately will strongly influence any future mining development. The Greymouth Coalfield has, however, had a long and eventful mining history spanning the last 120 years, where 32.5 x 106 tonnes of coal has been won from over 100 mines. In spite of the problems facing development, the large quantities and exceptional quality of the remaining coal will act as a strong inducement to persevere with this difficult but potentially valuable resource.

Jan 1, 1985

THE following notes, compiled in the first instance for the makers of rock-drIlls, were read by Mr. Hanton at a meeting of the Broken Hill Branch on 12th Septelnber, 1922. It was decided that all Broken Hill mines be asked to give their individual views on the subject, so that a comprehensive Broken Hill view could be published. Replies have been received from four (4), mines to date, and their'ideas fairly well coincide with those set out by Mr. Hapton. His notes were as follow:- "The Zinc Corporation Limited.NOTES ON ROCK-DRILL DEVELOPMENTSAs far as our present experience goes, the rock-drill developments on this mine will probably be something resembling the following. The programme is subject to modification or alteratian, according to circumstances. The results of further trials and improvements in present drills, and the design of new types, will, of course, affect any general scheme such as that outlined. It appears reasonably certain that the 3i-in. reciprocating drills which have done practically all the stoping up to date, will be gradually replaced by hammer drills of the internal water-feed type, and that the existing types of hammer drill on the mine will be converted into internal water-feed machines instead of being used as dry machine with outside jet.The ultimate types of machines will be four... Type 1 would be a machine equivalent to the Ingersoll Leyner: 248, Waugh Turbro, SullivaIi DX61, or Holman CH2. This would be used for driving, cross-cutting, and similar excavating work, and possiblyfor stoping also, and should be capable of efficiently working any class of ground. Features, apart from the general requirements set out later, would be the weight of the machine and mounting height of the machine above the seating (as this affects the convenience of boring back or bottom holes); absence of projections on the mounting which the air hose will foul as the machine is fed...

Jan 1, 1923

By Gartrell H. W

During investigations of the treatment methods for ore from the Bird-in-Hand gold mine carried out at Kalgoorlie and at these laboratories, it was found that excess alkali caused a lowering of extraction by cyanide, the cause of this being attrIbuted to the presence of a small amount of oxidised lead compounds in the ore. The subject has been discussed by various writers,3 but no satisfactory explanation of existing facts has been put forward. The experiments described in this report have been carried out with the object of obtaining some insight into the chemical reactions underlying the effect of lead salts and alkalis in cyanidation.The formation of cyanide-insoluble coatings on gold during roasting with lead compounds is well known, but the adverse effect of alkalis in cyanidation of ore is *This paper represents work done under a co-operative agreement between the Commonwealth Council for Scientific and Industrial Research and the South Australian School of Mines and Industries.Published by permission of the Mining Advisory Committee, Commonwealth Council for Scientific and Industrial Research.

Jan 1, 1935

By A Rozendaal

Namakwa Sands, a heavy minerals beneficiation business situated along the west coast of South Africa, is a major producer of titanium slag, pig iron, ceramics quality zircon and rutile concentrate to the international export market. The bulk of the economic mineralisation, which includes zircon, rutile, ilmenite and leucoxene is hosted by a late Cainozoic aeolian succession overlying remnant palaeo-strandline sediments. Relatively younger duricrust layers that cement a significant part of the generally unconsolidated ore compounds the challenging processing character of the primary mineralogy. The complex nature and hardness of the duricrust ore influence their mineability negatively, and can potentially destabilise downstream ore preparation processes. Effectively, up to ten per cent of the entire mineral resource is sterilised as the present infrastructure is not geared to treat the hard-mineralised ore. The metallurgical performance of the primary processing stage, which entails wet density separation, is strongly a function of the quality of the heavy mineral assemblage, liberation state of the economic minerals and slimes content. Elevated concentrations of garnet, a gangue contaminant exhibiting similar physical characteristics as the economic minerals, subtract substantially from the recovery performance of the secondary concentration process, which comprises mainly wet magnetic separation. By contrast, the intrinsic mineral purity of the economic fraction governs its successful recovery to saleable products as stringent product quality specifications apply. Improved mine planning through geometallurgical enhancement of the existing mineral resource model is envisaged to benefit the entire Namakwa SandsÆ mineral beneficiation chain, ultimately aiming to optimise mineral resource utilisation.

Jan 1, 2008

To the industrial geologist, as wen as to the general or historic geologist, the possession of a reliable key to the true order or sequence of the stratigraphy or position of the various upper rocky envelopes of the earth's crust, is, equally, a desideratum of the utmost importance. Of similar value to the two groups of students is the possession of facts which throw light upon the relationships which subsist between the puccessive rock formation of different countries, especially between countries lying close to each other, or within the same great geographical division.But there is necessarily a fundamental distinction which marks the respective limits of the field of observations of the industrial geologist, and the purely historic interest of the general geologist. The former has a more definite though less extensive scope. The scope of the latter is wide and indeterminate. In short, the observations of the industrial geologist are, 'from a commercial or economic point of view, of a more practical character, and are, therefore, intentionally restricted to the study of all geological questions which throw light upon the rocks which yield products of economic value and only include the study of the character and history of other rocks, in so far, as they afford aid to the more perfect comprehension of the best manner in which materials of economic value are likely to be sought, and the best means whereby these products may be secured for the material advantage of the community. The motive of the general geologist-in most cases-is a love of the study of some particular branch or province of the geological field, and the fascination of opening a new volume in nature's library, and the hope of extending the realm of knowledge, however slight, are often sufficient, as a motive, to enlist the energy and life's devotion of the true brethren of the hammer, irrespective of considerations regarding the commercial utility of the pursuit.

By G Anderson, M Mativenga, C Stanton, M Larson

Arrium’s magnetite concentrator has recently completed a modification program to improve the process that has been in operation in Whyalla, South Australia for the previous seven years. The magnetite concentrate is pumped via pipeline to the coast and serves as pellet plant feed, eventually being turned into steel in the Whyalla blast furnace. With the addition of a new 3MW IsaMill at the concentrator, the plant has seen increased production from a reduced feed grade, enabling Arrium to treat ores previously stockpiled as waste. This paper will focus on the design work and commissioning of the fine grinding circuit along with the year of optimisation that followed, taking the IsaMill up to 350+ tph of throughput.CITATION:Larson, M, Anderson, G, Mativenga, M and Stanton, C, 2015. The Arrium IsaMill from design through commissioning and optimisation, in Proceedings MetPlant 2015, pp 110–119 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 7, 2015

By J J. Boshoff

This iron ore mine site, located in the Pilbara region of Western Australia, commenced operations in 1998, with ore derived by mining of open-cut pits in Channel Iron Deposits (CIDs). A portion of the ore extracted at the mine is processed at wet processing plants that produce both ore saleable product and waste fines (i.e. tailings) slurry. The waste fines produced at the wet plants are presently stored within Waste Fines Cells (WFCs).Waste fines cells A (WFCA) and B (WFCB) are located within an Autonomous Haul System (AHS) area and consist of embankments that span the width of the pit in east-west alignments. Technical studies and design analyses were carried out to support embankment raises and ongoing development of the WFCs. During operation and development of the WFCs, a multitude of simultaneous activities took place to the immediate north and south of WFCA respectively. These activities included the construction of the embankment raises using the AHS fleet, mining of the CID to not only mine the ore but to also create future deposition space for WFCB, blasting next to the WFC embankments as part of the mining activities, seepage collection and dewatering of the pit in the vicinity of the WFC.This paper discusses the material characteristics, design approach, construction staging and equipment requirements, blasting near embankments, water management, facility consequence category and closure concept.CITATION:Boshoff, J J, 2018. A waste fines cell with a multitude of concurrent activities, in Proceedings Mine Waste and Tailings Stewardship Conference 2018, pp 39–49 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 23, 2018

Determination of Flotation Kinetics of Coal Grain Types in a Pilot Scale Jameson Cell using Coal Grain Analysis Method

Sep 13, 2010

THE object of the present paper is to give a brief description of the metallurgical process followed by the Grand Junction Co, and the results obtained therefrom. All figures quoted are from the actual working of the plant over a period of six months from January to June, 1910. The short ton of 2000 lb. is used by the company. Its gold is valued at 84s. per oz. fine, silver at 2s. per oz. fine. The ore consists essentially of a gangue of quartz and calcite, with 8 to 10%sulphide-pyrite, sphalerite, galena, chalcopyrite, and traces of arsenic and antimony. The colmtry-rock is a highlyaltered dacite. Small stringers of highly-mineralized ore penetrate the footwall of some of the lodes, forming a valuable stockwerk up to 3 ft. in thickness. In stoping, this is mined with the well defined lode, thus bringing into the mill at times a considerable quantity of hard country-rock. The gold exists in an exceedingly fine state of division, consequently rendering it necessary to grind very fine to obtain a satisfactory extraction.

Jan 1, 1912

By Yindong Yang

Despite the importance and usefulness of basicity in metallurgical slags, the optimum quantitative expression of it has remained elusive, partly due to the fact that the precise concept of basicity has not been properly clarified. The two basic approaches to the concept of basicity are the Lux-Flood, which perceives basicity in terms of the activity of the free oxide ion, a O2- , and the Lewis, which perceives basicity in terms of the ability to donate negative charge. The former has been almost universally adopted in the area of metallurgical slags, while the latter has been increasingly accepted in the field of glass chemistry. In this paper, some difficulties of the Lux-Flood approach are pointed out, including the need for indirect measures of a O2- , which have proliferated in recent years. Accordingly, it is suggested that the Lewis approach has a good deal to commend it, and that the quantification of it in terms of optical basicity is the best measure of basicity available, which should therefore be more widely applied in metallurgical slags than it currently is. The fact that there are intrinsic problems in evaluating the optical basicities for the transition metal oxides is acknowledged, and a new scale is recommended. The patterns of iso-optical basicity lines in ternary systems are shown to agree well with the pattern of iso-activity and iso-capacity lines under appropriate conditions. * Originally published in the Proceedings of MINPREX 2000, published by The AusIMM.

Jan 1, 2001

By A Giblett, R Dunne, D Appelhans

There are a number of hurdles that must be negotiated in order to design an effective gold ore treatment facility such that the expectations forming the basis of project economics are valid and can be achieved in practice. Selecting samples based on geometallurgical context, performing and interpreting testwork relevant to the selected process flowsheet are essential considerations towards achieving this aim. This paper discusses recent experiences in process development for free milling gold ores giving consideration to frequently encountered challenges of this nature.CITATION:Giblett, A, Appelhans, D and Dunne, R, 2013. Considerations for effective gold process development, in Proceedings MetPlant 2013 , pp 445-454 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 15, 2013

By P Vasconcelos, X D. Deng

Numerous supergene manganese oxide deposits are developed inSouth China as a result of weathering of a thick sequence of Paleozoic marine Mn-bearing sedimentary rocks, consisting mainly of limestones, cherts and black shales that were intensely folded and faulted due to multiple episodes of tectonism since the late Triassic. The ore minerals are dominantly pyrolusite, cryptomelane, nsutite, lithiophorite and braunite. The supergene manganese ores contain Mn ranging from 20 to 44 wt per cent; manganese oxide deposits derived from cherts and black shales also contain recoverable levels of Co, Ni, Cu, Pb and Zn. 40Ar/39Ar dating of potassium-bearing manganese oxides reveals that extensive supergene manganese ore formation started at least in the earliest Miocene and persisted to the Present. Ages of the deposits show a close correlation to tectonic stability, with the oldest in tectonically quiescent areas and the youngest in active areas that have subjected to continuous uplift and thus significant denudation. The prolonged wet and hot climate since Oligocene and the balance between weathering and erosion, which is parameter to the tectonic stability, are the ultimate controls on the formation and distribution of South China supergene manganese oxide deposits. An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

The State of New South Wales is highly favoured in having vast deposits of coal adjacent to and within easy reach of the coastal Ports. Not only is the quality of the fuel generally superior to any found in the other States, but it is greater in extent than in any other part of the Continent. For interesting and reliable details of the history of the discovery of coal, the geology of the coal bearing strata, analysis of the various coals and other valuable data, the readers are referred to the book recently issued by the New South Wales Government, entitled The Mineral Resources of New South Wales, by Edward F. Pittman, A.R.S.M., etc., by the direction of the Hon. T. L. Fegan, Minister for Mines. The mining community is indebted to the Minister for having had published the most valuable condensed record of the mineral resources of the State extant.For the purposes of this paper we will only give such a general description of the coal fields as will make it intelligible in connection with the subject of the coal mining in the State of New South Wales.

Jan 1, 1904

Leading Article from "British Medical Journal," London, 4th, November, 1944.Assuming that silica exerts its injurious effect upon animal tissue through a slow transformation into silicic acid, Denny, Robson, and Irwin thought that if the solubility of siliceous material retained in the lungs could be suffciently reduced the usual fibrotic response could be diminished or prevented. They discovered that aluminum powder rendered siliceous material insoluble in vitro by coating the silica particle with a thin film of gelatinous hydrated alumina, which on drying formed crystalline alpha aluminum monohydrate. The presence of this adsorbed layer on the surface of the quartz was shown by staining it with aurin. That metallic aluminum dust produced no fibrosis in the lungs was demonstrated by dust-inhalation experiments on eight rabbits. Attempts were therefore made to prevent silicosis by mixing quartz with metallic aluminum dust.Animals exposed to quartz dust developed typical silicosis in about five months, but the addition of 1 per cent. aluminum powder prevented this even after exposure had been lengthened up to 22 months, provided the aluminum powder was of a particle size below 5. This year Crombie, Blaisdell and MacPherson have reported the treatment of 34 silicotic miners by the daily inhalation of fine aluminum powder freshly ground from small aluminum pellets in a specially constructed mill. Daily treatment began with five-minute inhalations, which were gradually increased to 30 minutes. Some of the men received 300 treatments, but the majority only 200. Out of the 34 cases thus treated clinical improvement was manifested by lessening or disappearance of shortness of breath, of cough, of pain in the chest, and of fatigue. In 15 cases the condition became stationary and remained so in spite of continuous employment in silica dust throughout the treatment. The progress of the disease was assessed by means of tests for respiratory function repeated at three-monthly intervals. Obviously this treatment cannot be regarded as a cure for silicosis, since it cannot restore lung tissue which has undergone fibrotic change; but Crombie and his colleagues believe that the inhalation of finely particulate aluminum powder offers every prospect of preventing the development of human silicosis.In view of these findings, it is surprising that repeated papers by Goralewski from Germany describe various types of lung disease attributed to aluminum dust, and press for them to be scheduled under the Workmen's Compensation Act in that country. Seven hundred workers were investigated. They were making, probably by a stamping process, aluminium powder containing about four milliards of particles of dust per grain, and are reported as complaining of dry cough with pain on breathing, shortness of breath, poor appetite, and gnawing abdominal pain. Spontaneous pneumothorax developed in four workers. No abnormal physical...

Jan 1, 1945

The Southern 'B' lode orebody at the New Broken Hill Consolidated Limited (NBHC) mine, Broken Hill, is a continuation of the zinc-rich orebody that was first mined in NBHC in the 1940's. Preliminary diamond drilling in the early 1960's resulted in sufficient information to delineate the southern extension of the presently mined 'B' lode orebody, In 1966 the sinking of a 7.3 metre diameter circular shaft (No. 3 Airway) was commenced to improve the ventilation of the southern extremities of existing workings and to provide a base to further explore and develop the orebody extension. Development on four levels was started in the early 1970'.s to link the existing workings with the new shaft. Three possible mining methods - sublevel open stoping, loader cut and fill with ramp access and sublevel caving - were investigated and the decision was made to mine the orebody by transverse sublevel longhole stopes and pillars with trackless equipment and ramp access between the major working levels.

Jan 1, 1977

The Development of a Non-Roasting Technology for Polymetallic Gold and Silver-Bearing Sulfide Concentrates Treatment

Sep 13, 2010

By Morsky P, Kalapudas R, Natunen H, Virtanen M

The development of autogenous grinding modification in Outokumpu, known with the name 'Outogenius Comminution', was 'reversed'. At first the metallurgists studied and tested tens of years autogenous grinding in detail in full scale circuits at the concentrators of the company. After the final solution already had been found, also a pilot plant was built and now finally, research work is under way to develop a special laboratory method for testing the suitability of ores for 'Outogenius Comminution'.

Jan 1, 1993

By Pfeifer H. C, Nicacio P. A D

Sinter has been used as part of the metallic charge in large-scale blast furnaces for many years with the well-known benefits in terms of productivity and fuel consumption. However, because of the high investment in a conventional sinter plant, small blast furnaces and the associated integrated mini steel plants have not taken the advantages of using sinter. Recently KTS Korf Tecnologia Siderurgica, a division of Mannesmann Demag Ltda in Brazil, has developed a mini sinter plant for which the investment is compatible with small blast furnaces. Consequently, it is of great interest to evaluate the economical impact of using sinter in such small-scale integrated steel plants. In order to compare two alternatives, ie 100 per cent ore and 70 per cent sinter in the blast furnace burden, mass and heat balances for the entire operation from sinter plant through the blast furnace and EOF-based melting shop, were performed to evaluate the final production cost of the liquid steel. It was found that, depending on the sinter feed price, substantial savings can be obtained with the use of sinter.

Jan 1, 1999