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In his letter of resignation as General Superintendent of the Broken Hill Associated Smelters (BHAS) prior to taking up aconsulting position at imperial Smelting, G.K. Williams wrote that he considered his major contributions at BHAS were:the development of large scale sintering machines;the double tuyere-row blast furnace; continuous lead refining.Despite his well deserved reputation as a scientist, based on his advancement of the metallurgical chemistry underlying lead refining processes, Williams reveals that he considered commercial implementation as the ultimate measure of technological success. Furthermore, he clearly did not differentiate between the scientific and the empirical as a means of achieving that end.

Jan 1, 1985

By De Broglio R

The Mae Moh coal deposit was discovered some 60 years ago by villagers who noticed spontaneous combustion of coal outcrops. The first production began in the 1950's to fuel a fertilizer plant and a 12.5MW power station. During the period 1976 to 1979, three 75MW power station units were constructed on site. These have a total daily coal consumption of some 5000 tonnes and are served by a stockyard of approximately 60 000 tonnes total capacity. Stacked coal is reclaimed by means of a front end loader onto reclaim conveyors. During the years 1983 to 1986 four 150MW power station units were constructed east of the eastern seam subcrop, sons 2 km from the original power station complex. These have a daily coal consumption of nearly 12000 tonnes and are served by a stockyard of total capacity 270000 tonnes, equipped with two stackers and two bucket-wheel reclaimers for a totally mechanised system.

Jan 1, 1986

The correct assessment and understanding of geotechnical conditions is fundamental to mine design and, hence, successful (safe and efficient) mine planning, design and operations. However, this assessment and understanding is simply not possible unless there is a sound appreciation of the geology of the project. This paper addresses geological uncertainty in mine engineering and its communication, and shows that a mining project that does not take geology properly into account in the engineering phase is fraught. Uncertainty levels become excessive, which leads to hazards and consequential risks in design and operations in terms of both safety and efficiency. Several examples, both positive and negative, are provided to make the point. The paper concludes that mining geologists must become more overtly cognisant of the influence of geology on mine engineering. Equally importantly, mining (and geotechnical) engineers must communicate better with their geological colleagues to ensure that they (the engineers) have a clear understating of the geological issues affecting their operations. The engineers must know how to ask the right questions of the geologists. Engineers who do not understand and take account of geology in their designs and operations are failing the expectations of stakeholders.

Jan 1, 2006

By Warrillow C

Petroleum and mineral exploration share a common objective; to find and exploit commercial reserves of the desired commodity. Some exploration techniques are similar, others widely different.In peripheral matters such as permits, regulation procedures, land and compensation, there are many similarities. Despite this, the percep-tions and expectations of landowners and other interested parties reflect to a large extent the methodological differences between mineral and petrol-eum exploration. This can cause compensation demands and regimes to be vastly different in the two sectors.

Jan 1, 1994

By Torckler L, Brathwaite R. L

At Neavesville gold-silver (electrum) mineralization occurs in steeply-dipping zones of intense fracturing, brecciation and quartz veining within rhyolitic pyroclastics, carbohaceous shales and andesites. Hydro- thermal alteration extends over an area of greater than 3 by 1.5 km. In rhyolitic tuffs, highly silicified zones containing quartz- adularia-illite assemblages are flanked by less silicified assemblages composed of albite, illite-montmorillonite and chlorite. The mineralogy ana sequence of alteration are comparable with the alteration zones which envelop the steam-producing fissures of the active Wairakei and Broadlands geothermal fields. Primary fluid inclusions in quartz from five fissure veins in the Neavesville field show maximum homogenisation temperatures ranging from 220 - 260¦C and salinities of 0.0 - 1.1 wt. % NaCl equivalent, which cover a similar range to actual measured temperatures and salinities in geothermal fluids at Wairakei aria riroaolan¦s. The age of the rhyolitic pyroclastics and related alteration and mineralization is probably Pliocene and Neavesville therefore represents a fossil geothermal system.

Jan 1, 1980

By M D. Rosengren, G Gregor, M F. Young

Over the last 15 years the silver/lead/zinc ore treated at Mount Isa became increasingly complex and lower grade. Metal recoveries dropped dramatically, causing a serious decline in profitability. The ætraditionalÆ response of increasing tonnage to reduce unit cost was unsuccessful, since the additional tonnage was even lower quality ore. A major technical and capital program in the 1990s restored metallurgical performance, but business return was still too low and ore quality continued to decline. In 1996 a new, holistic approach integrated the steps of geology, mining, concentrating, smelting, and refining. Previous assumptions about æfixedÆ and æmarginalÆ costs in mining and processing were shown to be wrong. Detailed analysis showed that some ore sources were reducing profit. This led to a fundamental redesign and downsizing of both Mount Isa and Hilton mines. The result was dramatic increases in head grades, metallurgical performance and plant stability without any capital expenditure. The business is now smaller, but more profitable.

Jan 1, 1998

By S Shipard

Filters are used in water treatment and hydrometallurgical process plants for objectives such as generating a dry spadable solid, pumpable high density slurry or high purity filtrate. The priority objective of every polishing filter, sometimes also termed clarifying filters is high purity filtrate and these are found in many diverse industries and even different applications within the same industry.To generate a high purity filtrate, process designers have the choice of many different polishing filter products, but in reality very few polishing filters are based on fundamentally different filtering concepts.This paper reviews the technology merits of well-known and the more recently developed polishing filter products and aims to assist metallurgists and engineers with the selection of an appropriate polishing filtration technology for pregnant liquor filtration and other process applications, plus a guide to best practice.CITATION:Shipard, S, 2013. Polishing filters for mineral processing plants, in Proceedings MetPlant 2013 , pp 118-125 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 15, 2013

By Lauha E. A

The Goldstrike Mine is in Eureka County, Nevada, U.S.A., approximately 23 miles northwest of the town of Carlin. The mine is at the north end of the Tuscarora Spur of the Tuscarora Mountains at elevations of 5,300 feet to 5,950 feet. It is part of the Bluestar/Goldstrike subdistrict of the Carlin Trend, a northwest alignment of sediment hosted, disseminated gold deposits. The Carlin Trend includes over 15 major gold deposits with production, reserves and geological resources of approximately 65 million ounces of gold (Figure 1). In the Bluestar/Goldstrike subdistrict, there are seven major deposits; Betze, Lower Post, Post, Genesis, Bluestar, Purple Vein and Deep Star, plus numerous smaller deposits (Figure 2). Production, reserves and resources for the subdistrict are approximately 40 million ounces. Betze and Purple Vein are located on property controlled by Bamck Goldstrike Mines and Bluestar and Genesis on Newmont Gold property. Post, Lower Post, and Deep Star occur both on Barrick and Newmont Property.

Jan 1, 1991

By M Olsson, I Bergqvist

A Swedish table of blast damage depths has, in one form or other, been in use since the late-1970s. Its history and the underlying theory are described. New experimental and theoretical findings that point out a number of shortcomings in the table and the underlying theory are presented and discussed. A revised version of the blast damage table was recently introduced in conjunction with new but incomplete recommendations for cautious perimeter blasting. The new table leaves the difficult task of taking into account factors like decoupling, water in the borehole, the rock properties, type of initiation, charge length and the actual bit diameter to the user. This paper discusses different ways of doing this, based on the experimental findings and a recent formula for the prediction of the lengths of radial cracks behind the half-casts. The material presented in this paper is meant to supplement and extend the new Swedish recommendations for cautious perimeter blasting of tunnels, shafts, pits and road cuts.

Jan 1, 2001

By Gupta A, Hall ST

The grinding characteristics of quartz which is normally associated with gold bearing ores in Kalgoorlie area was examined in a stainless steel laboratory size ball-mill in the presence of inorganic and organic surface active reagents. The cationic species considered were Fe3+, Cu2+ and Ca2+, and the anions were CO? and S2 as these are normally present during the process of grinding of gold ores in the region. The organic surfactants examined were K-amyl- xanthate, dodecylamine-hydrochloride and the Grinding Aid XFS-4272 manufactured by Dow Chemical The study was primarily based on an examination of the electrokinetic properties of quartz surface in the presence of the grinding reagents. Zeta potential at different reagent additions and pH values in the presence of individual reagents were examined and the corresponding grinding charcteristics determined. A correlation has been indicated between the grinding characteristics, as measured by the -53um size fraction produced, and the surface energy of quartz. It was observed that an

Jan 1, 1978

The Quiruvilca district, located 80 km east of Trujillo in north central Peru (Fig. 1), has produced over eight million tons of Cu-Pb- Zn-Ag ore from approximately 60 veins since 1789. "Quiruvilca means "sacred tooth" in Quechua, the lingua franca of the Incas. The expression refers to a prominent volcanic neck exposed several kilometers northeast of the district. The district covers an area of approx- imately 24 km2. The mines occupy the eastern quarter; workings underlie 6.7 km2 with a developed vertical range of 280 m. All pres- ently operating workings are owned by Corpora- cion Minera Nor Peru S.A., a subsidiary of ASARCO Incorporated. The oldest rocks in the area are Lower Cretaceous clastic sedimentary rocks exposed 7 km to the east. Lithologies include sand- stone, siltstone, shale, coal seams, and carbonates (Cossio, 1964). These rocks were folded and affected by regional low-grade metamorphism during the early Tertiary, 40-65 m.y. (Hollister, 1977).

Jan 1, 1987

In 1969, Queensland Mines Limited obtained two large Prospecting Authorities in Arnhem Land, Northern Territory, Australia. The Nabarlek uranium deposit containing some 12 000 t of U308 was discovered on one of these in June 1970. Mining and stockpiling of this deposit were completed in 1979 and processing to yellowcake, which commenced in June 1980, is expected to occupy an 8-10 year period. The continuation of exploration, essential for the company to become a longer- term producer, was inhibited in 1972 by a Federal Government "freeze" on exploration in Aboriginal Reserves in the Northern Territory. Subsequently, the procedure for explorers to gain access to exploration areas in Aboriginal land was radically changed by the proclamation of the Aboriginal Land Rights (Northern Territory) Act 1976. As a result of this Act and the associated administrative policies adopted by Governments, Queensland Mines Limited has not yet regained access to the exploration areas it formally held in the early 1970's.

Jan 1, 1986

By C Czerny, T Elkington, L Lorenzen

The Dutwa Nickel Project is a nickel laterite atmospheric leach project located in Tanzania that has been under development by African Eagle Resources plc (2012). A bankable feasibility study (BFS) has been progressed to evaluate mining of the resource (107 Mt at 0.92 per cent Ni) followed by hydrometallurgical processing on-site to make a mixed nickel-cobalt intermediate product. The unique relatively high silica contents in the Dutwa deposits, as opposed to limonite, which is more commonly occurring in nickel laterites, presented the possibility for beneficiation of the ores to enhance the leach feed nickel grades and provide economic benefits in terms of operating and capital cost efficiencies.Geometallurgical relationships, based on the results of an extensive variability metallurgical test work program for beneficiation and leaching, were developed for the BFS, which resulted in an improved understanding of ore classifications within the deposit and their responses. The geometallurgical information obtained has been instrumental in making key preliminary techno-economic decisions, such as forecasting whether or not mined material should be beneficiated and was ultimately used to drive the mine plan towards the prioritisation of areas within the deposits that delivered the best cost efficiencies and overall project economic outcomes.CITATION:Elkington, T, Lorenzen, L and Czerny, C, 2013. The use of geometallurgical relationships in process route selection and mine plan optimisation for the Dutwa Nickel Project, in Proceedings The Second AusIMM International Geometallurgy Conference (GeoMet) 2013 , pp 207-216 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 29, 2013

By Greaves J. N

The U.S. Department of Interior, Bureau of Mines, is investigating the treatment of refractory gold ores. Chlorination in the treatment of refractory gold ores is applicable in many low-grade gold operations. When usable, this treatment provides an economic means of consuming sulfides and deactivating disseminated organic carbon. Chlorination, however, is a pretreatment technique that requires the neutralization of the chlorine prior to leaching the ore with cyanide. Research by the Bureau has extended the present chlorination technology to allow for the recovery of gold without the use of cyanide and allow treatment of some ores presently deemed untreatable by gold operators using cyanidation or chlorination/cyanidation techniques. Chlorination without carbon of two carbonaceous ores extracted between 1 and 20 pct of the gold; however, carbon-in-chlorine (CICL) treatments resulted in about 90-pct recovery with a reduction in carbon loading. A statistical design campaign for stripping metallic gold from the carbon loaded in a chlorine environment demonstrated elutions exceeding 90 pct.

Jan 1, 1991

The Honeymoon Well nickel sulphide deposits are located in the Agnew-Wiluna greenstone belt, about 45 km south of Wiluna. Both disseminated and massive sulphide nickel deposits are hosted by komatiitic rocks within the deformed and metamorphosed Honeymoon Well ultramafic complex. Fresh ultramafic bedrock is covered by up to 50 m of highly conductive transported material which greatly hampers both exploration and understanding of the bedrock geology. In the early-1970s, mineralisation was discovered by diamond drilling geochemical anomalies defined by wide-spaced percussion drilling over ultramafics that had been outlined by ground magnetics. Subsequent drilling has defined a resource of 158 Mt at 0.71 per cent nickel (based on 0.4 per cent nickel cut-off, 300 m below surface, December 1995) in four deposits. Over the life of the project a wide range of geophysical techniques have been used including airborne and ground magnetics, time domain clectromagnetics (EM), induced polarisation (IP)/resistivity, gravity and downhole techniques including EM, IP and physical property Measurements.

Jan 1, 1996

By Ishikawa K, Kikuchi T, Tokairin Y

Roadheader, developed from coal cutting machines, is generally classified as a tunnel excavation machine for soft rocks in respect to excavation mechanism, machine structure, weight, engine output and so on. In recent tunnel works, however, there is an increasing demand for changing from blasting to mechanical excavation by roadheaders to avoid environmental problems such as noise and vibration. But there exist various difficulties in excavation of harder rocks by roadheaders. In order to explore the possibilities of roadheader excavation, we performed field and laboratory experiments. In the field experiment, roadheader model S-125 (Mitui Miike Machinery Co.,Ltd.) was tested for various rocks of wide range of hardness, and excavation capacity and wear of picks were measured. In the laboratory test, cutting performance of the picks was tested by our cutter testing machine. This report describes thr: of these experiments and discussions :n possibility of applying boom-type tunnelling machines to hard rock excavation based on these experimental data.

Jan 1, 1987

By Miyatani J. Asaki Z, Kondo Y

The oxidation of sphalerite particles of 60 to 100 mesh size was studied in a fluidized bed of low 02 concentration at 900¦C. Par- tial pressure of 02 in the fluidizing 02-N2 gas mixture was chosen between 0.0009 and 0.02 atm. In the region of p02 between 0.008 and 0.02 atm, the oxidation rate was lowered with the decrease of p02, and the unreacted-core model was applied. At lower pbelow 0.008 atm, the reaction rate was enhanced as compared with the calcu- lated values from the unreacted-core model. From microscopic examination, it was found that ZnS was evaporated at the particle surface and the dissociated Zn vapor was oxidized in the gas phase. Initial reaction rate and the distance between the surface of inner sphaler- ite core and the oxide shell were studied based on the model of enhanced oxidation.

Jan 1, 1980

In essence, these statements concur, However, management predominantly controls the organisation's communication environment (5), Consequently, the participation by employees in safety is greatly influenced by the quality of upward communication, (See section on authority for discussion on two way communica-ò tionò) Emotional survival contributes to the communications and it is said to occur as follows: -- We. aU tend to move towaAA 6.itw tLon,s which aid the achievement oj5 owc goa o and way {y/wm ones which testh ict achievement." Consequently, although the work force are prepared to contribute, they will not make the effort for long if management does not respond in deed. The Robers report includes the following statement; "Satiety and heat h at wank is a matte o6 e66ic,ient management. But it .L not a management pn.enogative. Wank people muht be encouAagad to pattiaipate úu.Uy in the making and movutoni:ng ob a/vua.ngements ban .6aJety and heath, at their. pace ofj wonk.t'(3) Attitudes dominate within this region. Emotional surviv- al is paramount. Management is the catalyst. They dominate the communication channels. Participation does not exist without two way communications and positive responses by those involved, Fault Doctrine. Eliminate faulty human behaviour. This concept lives with us as the predominant prior- ity of many safety programs. The concept is a drain on limited resources., Remember, malaria. At one stage this disease was believed to be caused by the mat or bad air emanating from persons whose profaneness or impious behaviour incurred such reprisal. Today, such a concept of malaria seems so ridiculous, (9)

Jan 1, 1979

The Tregoora Gold Project is centred around the old Mitchell River Antimony Field located 100 kilometres west-northwest of Cairns, North Queensland. The project is currently the subject of a joint venture between Strategic Minerals Corporation N.L. and Hawk Investments Limited.Historical BackgroundThe Tregoora area was first prospected for antimony and gold around 1890. During the periods 1905 to 1914 and 1937 and 1944 approximately 100 tonnes of antimony and an unknown quantity of gold were won from a number of small mines the principal one being the "Retina". A strong increase in the demand for antimony in the early 1970's resulted in renewed exploration activity in the region and the re-development of the Retina Mine. Despite the intermittent interest in the region for antimony it was not until 1984 that the potential of the area for hosting gold resources was realised with the delineation by Strategic Minerals Corporation N.L. of a significant gold deposit now referred to as the Black Knight.

Jan 1, 1986

By Hedley TP

Success for underground coal mine operators in the 1990's and beyond will be dependent upon better understanding of the dynamics of their operating environment, and extension of emerging technologies to reach new levels of output and productivity. The Collieries Division of B.H.P. Steel International Group clearly identifies with the concept of business/product life cycles - and the need to adopt strategies that can drive the business successfully into the future. Three main thrusts within BHP Collieries Division relate to: 1) Detailed assessment of current mines to determine: a) The real output potential of the current facilities. b) What factors now inhibit the full potential from being realised. c) Opportunities that exist to enhance overall mine performance. 2) Based upon the findings of these studies, putting into place cost effective strategies and systems for the ongoing "tuning" of the mine. 3) of new/improved technology primarily in areas of: a) Coal cutting and underground coal clearance. b) Controlling the overall mine gas Regime.

Jan 1, 1987