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THIS paper is the outcome of experiments carried on and experience gained. at the Waihi-Paeroa Gold Extraction Company's tailings plant at Waihi, New Zealand. The plant was erected to treat accumulated tailings which had been discharged into the Chinemuri River by the Waihi batteries.The Chinemuri River is a common sludge channel for all mining debris, tailings, and ashes from the power plants, the last being the cause of occasional high residues, which gave so much trouble to the management. The tailings were dredged from the bed of the river into barges by means of a Pohle air lift, the power being supplied: by a 13 b.h.p. Tangye oil engine driving an air compressor and a centrifugal pump. The sands were elevated from the barges by bucket-belt elevators over screens, to eliminate large particles and rubbish, into storage hoppers, and from there fed direct into four C. Judd Ltd. tube mills.The method of treatment was fine grinding in a weak cyanide solution, agitation in B. and M. tanks, filtration with turn-over vacuum filters, and precipitation with zinc shavings. The comparatively high values of the residues in gold gave a great deal of trouble, 'and it was not until repeated experiments were carried out that the cause of the trouble was located. While the value of silver residues remained stationary, the gold values...

Jan 1, 1912

Analyses of scheelite from all the known scheelite fields in the South Island of New Zealand have shown that the scheelites are essentially molybdenum-free. The scheelites are almost stoichiometric CaWO4, except for some strontium replacing the calcium, with a maximum of 0·92 per cent SrO. Variation in strontium content appears to be' related to the metamorphic grade of the enclosing rocks.

Jan 1, 1970

By Healy T. W, Dixon D. R

The present study 'of pure ZnS and NiS and ZnS (marmatite) by detailed electrokinetic methods has shown that by careful control of experimental parameters much new' information on sulphide-water interfaces can be obtained. Time-dependent processes of alteration of sulphide surfaces are foHowed by electrokinetic methods and indicate that the isoelectric point of the surface depends on elemental sulphur coverage, oxidation product coverage, and the conditions which promote or minimize such reaotions in the presence and absence of activator.

Jan 1, 1977

By P Allen, E Gleeson, D Boakye, R Chesher, S Konopa

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. Not only do epithermal gold deposits provide many challenges in estimating mineral resources, the complexities of these deposits also provide technical challenges in assessing appropriate mining and processing strategies, as well as social and environmental planning and management. The characteristics of epithermal gold deposits include being highly variable with respect to geometry and gold grade distribution, the presence of other economic contributors, mineralogy, texture, rock strength, weathering and alteration overprint. These characteristics influence the economic value of mining projects in an interlinked manner. Consequently, successful exploitation of epithermal deposits requires a holistic approach, coupled with the effective integration of geological data to meet all aspects of mine development decision-making. This paper presents examples of the key technical challenges encountered in estimating and mining epithermal deposits. It also highlights why these issues need to be addressed from the viewpoint of geology, sampling, resource estimation, mine planning, mineral processing and social and environmental planning for the true value of the mining project to be realised.CITATION:Konopa, S, Chesher, R, Gleeson, E, Allen, P and Boakye, D, 2015. Challenges in maximising the value from epithermal gold deposits, in Proceedings PACRIM 2015 Congress, pp 127–132 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

CrusherMapperTM - A New Tool for Crusher Condition Monitoring The efficiency of mineral processing plants is entirely dependent on the availability of the plant equipment critical path. This typically concerns comminution circuits consisting of primary crushers and primary grinding mills. Crusher and mill availability are determined by the frequency and duration of maintenance shutdowns, which are primarily driven by the need for replacement of sacrificial liners. The change of crusher and mill liner shape over respective life cycles also strongly affects plant efficiency. It is therefore highly desirable to accurately monitor the condition of mills and crushers in order to optimise plant efficiency through maximised availability and targeted liner shape. Traditional comminution liner and other production parameter condition monitoring has been attempted through ineffective methods which prevent satisfactory management of crusher and mill maintenance and reduce operational control. This situation has recently dramatically improved for grinding mills through the development and commercial deployment of MillMapperÖ, a technology based on three-dimensional laser scanning data and dedicated software (Franke, Lichti and Stewart, 2006; Franke and Lichti, 2007; 2008; Franke, 2008; Franke, Redman, Johnson and Michalek, 2009). At the time of writing in late 2009, MillMapperÖ is in successful use at a rate of approximately 170 surveys and associated reports per annum at processing plants in Australasia, South America, North America and Africa. This paper presents the introduction of CrusherMapperÖ, the MillMapperÖ equivalent for crushers. CrusherMapperÖ also utilises high density, high accuracy laser scanning data, and features dedicated algorithms for three-dimensional monitoring of wear on crusher concaves and mantles. This facilitates the detection of wear hot spots or zones or localised liner failures, and accurate forecasting of reline tonnages and dates. It also for the first time provides the means to establish optimised concave and mantle shapes in order to achieve production targets. In contrast to any other currently utilised condition monitoring method, CrusherMapperÖ data collection can occur remotely and does not require any shutdown or crusher isolation. This method therefore does not interrupt crusher production while at the same time eliminating any confined space risk normally associated with taking measurements inside the crusher cavity.

Sep 13, 2010

The extent of regional stratigraphic and structural geological mapping so far carried out in Australia is likely to be greatly overestimated by uncritical inspection of the latest authoritative geological map of the continent-that so ably compiled by the late Sir'T. W. Edgeworth David. Vast areas geologically coloured on this map are in fact known only from the most meagre field data, some of Which even include observations of distant views from which the so-called "geology" has been indicated in' reconnaissance reports.This applies to large areas in Cape York Peninsula; the plateau of Arnhem Land, and its margins except on the west where the Pine Creek mineral belt is better known; to the Desert Basin of Western Australia, practically the whole of the western half of the Northern Territory, much of east-central Western Australia, and northwestern New South Wales. Other vast areas are, more happily perhaps, left blank. It is true that prospecting parties have, at various times and with varying degrees of thoroughness, traversedparts of these little-known regions, often, however, in the search for gold or the.more obvious types of metalliferous mineral deposits and, furthermore, too often without leaving any written account of their examination, or with very sketchy details supplied. Unpublished geological surveys also cover some parts of these regions, but, on the whole, the picture we can draw of the regional deployment of rock masses in Australia is far less full than even David's map, with its obvious blanks, presents to us.Lest the practical mineral seeker among us should be inclined to place too much reliance on the prospecting to which I have referred.as giving him a straight hint of what country to keep out of, we may point to the recent discovery of a major sedimentary basin in the east KimberllilYs on which Dr. Teichert will have more to say. And that there are new metalliferous mineral deposits to be foundin parts of these little-known areas no one can doubt, for, after all, new discoveries are made from time to time in areas so well-known as the Victorian gold-fields. I take it then that regional geological mapping is a necessary concomitant of the further development of Australia's mineral resources-but I am not of the school that places it first on the list of priorities, and furthermore I believe that there can be a royal road to regional mapping-an inspired approach based on knowledge already gained and led to fruition by field surveys in key areas, by which there may be obtained a result giving a significantly close approach to actuality with only a fraction of the work that would be required for detailed field surveys on a systematic basis. I believe that a policy of rapid reconnaissance of such a type should be adhered to, especially in view of present deficiencies in numbers of geologists available for all purposes in Australia. The details that must eventually be sought can, I believe, be filled in later as the whole country becomes more developed and amenable to detailed surveys.

Jan 1, 1950

Samples weighing O· 2 g are digested with 2 ml of 72 per cent perchloric acid for 2 hr at 180°C, and then diluted to 10 ml. with water. After settling, an aliquot of clear solution is reduced with ascorbic-citric acid, and then a zinc dithiol solution is added to form a coloured molybdenum complex which is extracted with petroleum spirit for comparison with standards.Concentrations down to 2 p.p.m. may be analysed at rates up to 150 determinations per day.

Jan 1, 1970

By G B. Arehart, J L. Mauk

Quartz veins from the Martha Hill epithermal gold-silver deposit, Waihi, commonly exhibit crustiform banded textures. Visual differences observed between bands are primarily the result of a 1 to 1500 ¦m variation in quartz grain size. Quartz band textures are dominated by anhedral interlocking quartz mosaics, commonly associated with minor adularia and sulphide phases; these textures are interpreted to be products of amorphous silica crystallisation. The occurrence of rhombic adularia suggests that prolonged boiling influenced parent fluids. In contrast, the presence of coarsely crystalline bands, made up of subhedral to euhedral quartz grains, infers primary crystal growth from solution; evidenced by the occurrence of growth-zoned quartz within these bands. There is a narrow range of 3.3ë in d18Oquartz between maximum and minimum isotopic values for the deposit. Significant overlap in d18Oquartz values are observed between the Martha and Welcome lodes. However, statistically significant and commonly systematic differences do occur between individual bands analysed in most samples. Temperature fluctuations may be the dominant factor responsible for observed inter-band variation.

Jan 1, 1995

By J Morton

The Resource Management Act 1991 represented an innovative and unique piece of planning and environmental legislation when it was introduced. Since the Act was passed into law in 1991 it has been subject to nine amendments, many of which were of the ætinkerÆ variety. These amendments recognise that the Act has not been as successful in providing the æone-stop shopÆ for resource users that the Act was hoped to be. The latest and most significant attempt at changing the Act was the Resource Management Amendment Act 2003. The amendments made by the Amendment Act have proved to be largely unsuccessful in achieving any significant changes to the way resources are managed in New Zealand, and have failed to address many of the concerns which drove the original Resource Management Amendment Bill in 1999. The recent decision to discontinue further investment in Project Aqua has once again placed the Act in the spotlight as a significant hand-brake on major projects. This particular event has led to yet another review to be undertaken this year. The review will focus on five key areas:   1.   achieving the right balance of national and local interests; 2.   improving the design and process for local policy formulation; 3.   improving the consent decision making process; 4.   allocation of natural resources (water, air and geothermal); and 5.   supporting measures for building capacity and promoting best practice and implementation at the local authority level.  It is important for the business community and the mining industry in particular to seize the opportunity that this review provides to make sure that any amendments undertaken as a result of the review achieve the aims listed above. The review needs to be considered in light of the current regime for the management of natural resources in New Zealand. In addition to the Resource Management Act 1991, the Crown Minerals Act 1991 and the Building Act 1991, which form the core resource statutes in New Zealand, there have been other developments affecting the regime. Special legislation over and above the Resource Management Act 1991 has been enacted to protect the Hauraki Gulf and special legislation is currently being considered to protect the Waitakere Ranges in Auckland. In the Hauraki District mining is prohibited in some areas and a plan change mechanism is specified as the appropriate tool to use in the event a mineral resource is to be developed in those areas. The current review is a further opportunity to remedy the inadequacies of the Act.

Jan 1, 2004

Two of the problems long associated with the complete extraction of level pillars in the wide ore bodies of Broken Hill have been: (1) The high cost of maintaining level gangways through areas of slow subsidence to provide adequate trucking roads for the transport of sand filling; and (2) The difficulty and high cost of completely filling depleted areas. This paper deals with the experiments conducted to devise an apparatus for transporting, with the aid of compressed air, sandfill from the underground sand passes to the stopes and describes the sand blower which has been developed. This apparatus has to a large degree overcome the difficulties and removed much of the hazard associated with the rapid extraction of level pillars.Special attention is drawn to the sizing analysis of the sand and to the fact that it is not dry material. It was early found that these factors were determinants in the design and development of the apparatus described.Acknowledgment is made to the General Manager of Broken Hill South Limited for permission to present this paper, to the engineering department for assisting in the design of the apparatus, and to the underground staff for their co-operation in training the operators and in bringing to success this method of stope filling.PREVIOUS FILLING METHODSThe South Mine, with a monthly production of approximately 32,000 tons of lead-sHver-zinc sulphide ore by cut-and-fill mining methods, requires about 11,000 cubic yards of filling per month. With the exception of a small and variable quantity of developmental mullock, all this filling is...

Jan 1, 1941

By R Byrnes, P Hensley

The outstanding environmental management initiatives undertaken by Novacoal at its Western Main Site near Lithgow in New South Wales over the past five years are detailed in this paper. These initiatives have been based on a combination of proven and innovative investigation and implementation techniques, close consultation with regulatory authorities and full support by colliery management. The results of these initiatives have enabled the colliery to exceed its pollution control obligations from a base well below industry standards. The initial poor condition of the mine was the result of over 50 years of traditional mining which paid little regard to environmental management. The transformation of the colliery within such a short period, with limited capital, is considered a model for the N.S.W. coal industry.

Jan 1, 1995

By D A. McCallum

With depth, many gold ores become sulfidic with minerals such as pyrite, pyrrhotite and arsenopyrite becoming prevalent. In addition, many underground gold mines use tailings backfill to bind and store the waste. In these cases, acid mine drainage (AMD) can become an issue. One approach to the control of AMD is desulfurisation whereby the sulfide minerals are removed prior to disposal. Four sulfide tailings samples, representing different ore types and gold and base metal operations, were selected for assessment and testing using simple physical beneficiation techniques. The aim was to determine the extent to which mineral processing methods were suitable for separating sulfides from non-sulfides and for extracting potentially marketable by-products from the tailings. In order to streamline the testing procedure a simple diagnostic separation technique was developed to enable quick screening of bulk sulfide tailings for suitability for reprocessing. The testing procedure involved detailed characterisation and a sequential set of testing regimes based on simple unit processes including water washing, classification, gravity concentration, magnetic separation and bulk flotation. The preliminary test results indicate each unit process can play an important part in producing effective sulfide/non-sulfide separations and in generating useful by-products from the tailings. Potential valuable products identified include coarse, benign silica sands, bulk iron sulfide products rich in pyrite and/or pyrrhotite, high-grade iron products (magnetite) low in silica, low-volume bulk sulfide concentrates and low-grade molybdenite and talc products. The work presented shows how sulfide tailings can be viewed as a resource rather than a waste stream, and identifies a pathway for developing a more sustainable approach to the environmental management of sulfide tailings for the future.

Jan 1, 2007

By M A. Mongillo

Most geophysical and geochemical data collected during regional exploration programmes are in vector form (location, value), and have traditionally been presented and interpreted in a profile or contour map format. However, the human vision system can interpret data presented in image format much more easily and new information is often revealed by the judicious application of powerful interactive computer image enhancement techniques. This paper describes a practical demonstration of the application of such tools to gravity and resistivity datasets from the Central Volcanic Region of theNorth Island.   Filtering, contrast enhancement, relief shading, pseudo-colouring and then overlaying of the gridded datasets in image format has helped identify inter-relationships such as the association between many low resistivity anomalies (epithermal deposits or geothermal resources) and the edges of large gravity anomalies (calderas or grabens). Similar revelations should result from the application of these tools to the integration of other mapped datasets from geophysical, geochemical and geological disciplines.

Jan 1, 1992

FOR many years past it has been the practice at the Bairnsdale School of Mines to treat any parcels of auriferous concentrates sent in from the surrounding district by roasting them in a handworked reverberatory, and then chlorinating or cyaniding the product. According to Donald CIark, who has done a large amount of work on these ores, the results obtained were fairly satisfactory extractions of over 90 per cent being claimed. With some modifications, the method has been very generally adopted, not only in Gippsland but throughout Victoria. It is, however, difficult to get exact information as to the extractions actually obtained, and unfortunately no records of working results have been kept at the Bairnsdale School of Mines.Having treated several lots of ore by this method during 1907 and 1908 with unsatisfactory results, the writers thought it desirable to make a detailed investigation on some particular ore, both in the laboratory and on a working scale. The ore selectedwas a parcel of low-grade concentrates from Stirling, a small mining field situated about forty miles to the east of Bairnsdale. This ore was chosen chiefly on account of the heavy and inexplicable volatilization loss which took place even on roasting with the greatest care; the loss amounting to between 10 and 15 per cent. In the experiments here related, three main objects were kept in view:-1. To determine with what mineral 01' minerals the gold and silver were associated...

Jan 1, 1909

By C Haughy, F F. Pitard

Blue Mountain Minerals is a large supplier of calcium carbonate products used by various manufacturers as a major raw material. Very small amounts of free carbon in the rock can have a huge impact in carbon-sensitive applications. The marble in the deposit at Blue Mountain Minerals contains variable amounts of free carbon in the form of trace amounts of the mineral graphite.To make quality improvements, variography was used to measure the impact of non-ideal sampling practices at the Blue Mountain Minerals operations in Columbia, California in the United States. A major investment in correct sampling systems and sampling protocols was implemented over a one-year period. Subsequent variography was used to measure the improvement on the predictability of the graphite content in marble produced by the quarry and as it is processed as an acceptable raw material for extremely carbon-sensitive applications. The improvements of the sampling protocols, control of long-range changes and better knowledge of process cycles are easily noticeable on variograms when they happen to exist. The economic impacts are discussed.CITATION:Haughy, C and Pitard, F F, 2017. Use of variography to measure improvement of sampling practices for the quality control of graphite consistency in marble used for carbon-sensitive applications, in Proceedings Eighth World Conference on Sampling and Blending , pp 255–260 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2017

The Australian metallurgical processing industry has shown great innovation and progressiveness over the past ten years. During the same period, exploration activity, particularly by Australian companies, has increased substantially in Indonesia. Following feasibility studies, the decision was made to establish a metallurgical laboratory and design facility in Indonesia. An Indonesian partner was selected, and legal and corporate matters were determined. The laboratory was established but proved far more difficult than a similar undertaking in Australia. Australian and Indonesian staff were recruited and training programs, including training of Indonesian staff in Australia, were implemented. Difficulties of operating in Indonesia included: ò language difficulties ò _ local pace of life ò culture ò communications. Rewards of the decision to establish the means to present the technology to Indonesia have included: ò a contribution to Australia's export of technology. ò an opportunity to expand Normet's client base. ò the opportunity to learn aspects of a foreign culture. ò the means to establish a sound long term investment. This export of technology from the Australian mining industry to Indonesia is an example of the initiatives and capabilities shown by the Australian mining service industry.

Jan 1, 1989

The past decade has seen revolutionary advances in communications and information-handling techniques which have been stimulated by "cold war" military requirements and by current programmes for probing into outer space. The tools used in exploration for petroleum and minerals have been improved significantly as a result of this new space age technology and even greater improvements are on the way.Two areas of technical activity have been particularly fruitful in enhancing the effectiveness of exploration methods. These are1. the development of new approaches, based on information theory,for extracting signal from noise more efficiently than before, and2. the use of high-speed digital computers for storing and processing all kinds of exploration information, not only geophysical but geological as well.In seismic prospecting, use of information theory has led to new techniques such as time-domain filtering, wave-number filtering and correlation methods which have made it possible to obtain usable reflection data from areas which were previously considered non reflective. Complex playback and other data processing facilities have been developed to apply these approaches.Digitization of geophysical data for handling by high-speed electronic computers facilitates many of these techniques for signal-to-noise improvement. Direct digital recording of seismic data in the field is now being d'one on an experimental basis in the United States, and this should become a standard procedure, at least for problem areas.The increased dynamic range, flexibility of filtering and other data processing, and convenience of information storage and retrieval make digital recording attractive in spite of its high cost compared to conventional analogue methods. Digital computers are being programmed to carry out many operations in data reduction and interpretation with substantial savings in time and cost over conventional procedures.INTROPUCTIONIn the years that have passed since the end of the Second World War, the western world has witnessed a technological revolution which may be as far reaching in its ultimate impqct as the Industrial Revolution of the last century.

Jan 1, 1963

This method determines tellurium at concentrations down to 0·01 p.p.m., with geochemical accuracy. Tellurium is volatilized from the rock at 800°C in the presence of sulphur from decomposing pyrite, condensed, dissolved, and finally determined by atomic absorption in a long tube burner. The distribution of Te is shown near some gold lodes at Kalgoorlie. Lastly, a method of synthesizing Te-free pyrite from sulphur and ferrous sulphate is described.

Jan 1, 1969

This evening I intend to explain the position of the gold mining industry in the light of post war trends and events.I propose initially to comment on gold production throughout the World and then proceed to the state of the industry in Australia, with an account of the efforts made within the industry to maintain levels of production. This will be followed hy a statement on assistance granted to the industry by Federal and State Governments.Annual World gold production is estimated at 51,000,060 fine ounces, made up as followsSouth Africa - 27,300,000 fine ouncesCanada 4,200,000 " "U.S.A. 1,500,000 " "Australia - 1,000,000 " " Others 5,000,000 " "----- 39,000,000 " "Estimated Russianproduction - 12,000,000 " "Total 51,000,000 " "The opening up of new highly payable mines during the post war years has contributed to the preponderence of production in South Africa.In 1962 some 24 new mines produced 73 per cent of South Africa's gold, and contributed almost 90 per cent to the industrial profits.At the same time, 20 old mines were struggling to main...

Jan 1, 1964

By M Eggers, H Baxter

This paper discusses the geotechnical condition of bedding shears and small- and large-scale faults and shears in Archean banded iron formation (BIF) bedrock, based on observations of core and televiewer images. Information that can be collected includes the orientation of defects, infill thickness, strength and material type, defect shape and surface roughness.The spacing and continuity of bedding shears may be critical to slope design where performance is structurally controlled with bedding dipping out of a wall. The intensity of development of the bedding shear is a useful indicator of the amount of shearing a bedding surface has been subjected to. This can allow for engineering judgement to be used in adopting peak or residual shear strengths along defect surfaces when developing the design.The spacing and continuity of bedding shears may also contribute to the blockiness and degradation of a rock mass where the structural orientation is otherwise favourable. Additionally the condition, thickness and strength of infill of major fault structures can affect slope design and performance, depending on orientation.Comparison of the condition of structures observed in core with the corresponding in situ televiewer image has been made to assess what characteristics are most accurately captured by each technique and whether the additional information gathered from using the televiewer technique is justified by the cost. The question of whether the data collected by a televiewer is sufficient to ultimately replace the need for core is considered.CITATION:Baxter, H and Eggers, M, 2013. Fault and shear characterisation in archean banded iron formation bedrock - a comparison between core and televiewer data collection techniques, in Proceedings Iron Ore 2013 , pp 47-56 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 12, 2013