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MR JOHN S Foxall wrote: Mr Clayton in his paper on the above subject (Proceedings, N.S. No. 34) made an assertion which should not be allowed to remain unchallenged. On the top of page 10 appears the following statement;- "By viewing the box at adepression angle of 45°, all the dimensions are disclosed and the box may be projected on isometric co-ordinates" and lower down on the same page:- "An isometric plan, being virtually a projection on a plane inclined at 45°, the nearer the dip approaches this figure so is the outline of the stoping more truly shown." Those statements embody an inaccuracy which would be misleading were an isometric plan to be constructed to suit a special case, ie the case of a mine whose lode dipped at 45°, or approximately 45° and it would be found that in such a plan the outline of the stoping would not be truly shown. The reason for this is that the depression angle at which an object is viewed in order to...

Jan 1, 1920

The report by Baker (1958, p. 27) of krennerite in contact with gold in a specimen from the 2500 ft level, Phantom South lode, Great Boulder mine, Kalgoorlie, led the writer to look into this further, since Cabri (1965) reported that the assemblage krennerite-gold was unstable between 238° and 356° C, and possibly down to room temperature.Dr. G. Baker very generously provided the writer with two chips from the same rock specimen (No. 14 as labelled from the mine) in which the krennerite gold assemblage was reported to occur. These were examined by polished section and x-ray diffraction techniques and returned to the classified collection of the Mineragraphic Investigations Section of CSIRO.One specimen, showing visible gold, was examined optically with a binocular microscope and telluride material was twice removed from contact with the gold for x-ray diffraction. This material proved to be petzite and so amends a statement by Baker (1958, p. 39) that no petzite was found in the Phantom lodes.The second chip was polished, and microscopic...

Jan 1, 1967

Case Study: Dragline Swing to Dump Automation By Peter Corke, CSIRO Manufacturing Technology/CRC for Mining Technology and Equipment (CMTE) Peter Corke presented a case study of a project to automate the dragline swing to dump operation. The project is funded by ACARP, BHP Coal, Pacific Coal and the CMTE and is being carried out on a dragline at Pacific Coal's Meandu mine near Brisbane. Corke began by highlighting that the minerals industry makes extensive use of large, mechanised machines. However, unlike other industries, mining has not adopted automation and most machines are controlled by human operators on board the machine itself. Choosing an automation target The dragline automation was chosen because: ò draglines are one of the biggest capital assets in a mine; ò performance between operators vary significantly, so improved capital utilisation is possible; ò the dragline is often the bottleneck in production; ò a large part of the operation cycle is spent swinging from dig to dump; and ò it is technically feasible. There has been a history of drag line automation projects, none with great success.

Jan 1, 1997

By Gabriella Mendez

Worthy of note in Miss Bailey's paper are her comments on the attitudes of mining companies and their managers where women were employed, she says, "..another possible pitfall is reverse discrimination where in an effort to avoid being branded as having shown a person favouritism, supervisors end up treating the person in a manner much less than they deserve. This is manifested in denying an employee such things as challenging work, educational opportunities, promotions, or in the case of staff, fair merit increases." and further she says, "It has been observed that the treatment of women in non-traditional roles such as mining is different than for men in the same environment. There are people who treat women worse and some who treat them better simply because they are of the other sex." These statements may sound unjustified to today's audience, and whilst we need to credit pioneering women with having tolerated, understood and worked towards improving the mining culture, the move towards total inclusion of women in the workplace is still growing.

Jan 1, 1995

Dynamic hydrothermal modeling is a tool that can aid in studying problems associated with hydrothermal ore deposits and can help increase our understanding of the spatial distribution of ore within hydrothermal systems. Models are constructed by a sequence of steps involving development of a conceptual model, followed by its mathematical description in terms of governing equation with accompanying initial and boundary conditions. This equation is then solved either analytically or numerically. The four model types ò that fully describe a hydrothermal 'system are those for fluid flow, heat and ore solute transport, and deformation. At Renison, models have been used to help understand two major exploration problems. These are the controls on ore localisation in dolomite horizons and feeder faults respectively. The types of models used ò have simulated the distribution of all mineral zones, pyrrhotite, and temperature in the dolomites. This has allowed evaluation of the effects on ore localisation by physical and chemical heterogeneities within the dolomite host rocks, and allowed estimation of potential controls in different physical and chemical environments.

Jan 1, 1987

By Jefferson CB

Adaptive optimisation is the adjustment of operating conditions to maintain optimum process performance as the feed quality varies. This strategy has the potential to be economic- ally better than the maintenance of a constant optimum performance with a blended feed. Application of the strategy is hindered by practical difficulties and economic risks. A computer simulation of leaching processes has been used to identify ore-process systems which have the greatest potential benefits from adaptive optimisation. They are systems with low value feed materials and a broad distribution of reactivities, in pro- cesses which are sensitive to the operating variable that is being manipulated (e.g. residence time). Improvements of up to 13% in throughput and 5% in the economic operating margin can be achieved. The results are sen- sitive to the precise model which is used for the process kinetics. It seems that the kinetics of the last few per cent to react are particularly relevant. A realistic situation has been identified where a synergistic inter- action occurs in blended feeds which makes adaptive optimisation disadvantageous.

Jan 1, 1984

The ore body being worked is about one hundred feet in length by seventy feet in width. A face of about fifteen feet is stoped over the whole level at one operation, this height standing without any timber.Double lines of logs, twenty feet in length and from ten inches to one foot in thickness at the small end, are then laid longitudinally, butt to butt, and breaking joint from end to end of the ore body they are at ten feet centres from wall to wall. The starting logs are single for the first ten feet and their ends are hitched into the solid rock. These are called "miners" and are the logs which are picked up as the level underneath is worked up. The double layer gives a better chance of picking up. Logs are now laid from the centre of the ore body at right angles to the miners, the ends being hitched into the walls. A space, seven feet wide, is left open right through the centre of the ore body...

Jan 1, 1904

By Stubbs B

In conjunction with Charles Copeman, we have arranged the presentation of a paper by Charles with a support paper by myself presenting alternatives to currentaccepted legal concepts involving the ownership of minerals by the Crown and the absence of ownership in any minerals or entitlement to benefit therefrom by the owner of the land on or under which the minerals occur.2. The current situation has its historical route in the concept of gold and silver being royal metals and belonging wherever situated in the Kingdom to the King and it is submitted it can be'seen as being archaic in nature perhaps even feudal and perhaps worthy in this day and age of reconsideration.Our purpose in these papers is to present an alternative view supported by argument challenging the present system and hopefully, creating room for comment and interchange amongst those involved in the industry. My solutions are not Charles Copeman's solutions and vice-versa. However, we do share a common belief that the present system may not be the best system.

Jan 1, 1990

The constraints in university courses are lack of hours, high cost of scientific equipment, and poor availability of suitably experienced staff. These have forced the balance away from practical work and towards more theory. Labelling of individuals as either practical, or academic, does not help the inter- change of staff between industry and univer- sities that is necessary to balance idealism and realism. Practical men who do return to universities may lose seniority and find that industry is reluctant to have them back. Academics who specialise too long may concentrate on their research to the exclusion of basic material. It is difficult to operate pilot scale plants in universities because of lack of time, and obsolescent equipment. Small grants from industry might enable tests to be run in research laboratories such as at C.S.I.R.O.. Within universities there may be a need for greater interchange of students among depart- ments, aided by the absence of weighted student unit measurements, as suggested by Aus.I.M.M. and A.M.I.C.

Jan 1, 1984

By Davison GR

The cost of drilling consumables is always a large component of any mine budget. It is important that this cost be carefully examined with a view to reducing the overall cost per inetre or at least minimising its escalation.At Renison it is considered that the only way to ensure drilling costs do not rise unduly is through a total system of control from purchase to disposal.In 1979 extension of an existing drill supply service contract was carefully examined and abandoned in favour of a hybrid system. This system is providing a great deal of control over the use of drilling consumables and has maintained a relatively constant cost per drilled metre over the last five years.Current consignment stock contracts for drilling consumables are strictly specified by the Technical Services section of the Mine Department and consumables purchased under these contracts are distributed and refurbished/sharpened by a contractor.The total result of this package is individual drilling items that achieve the best cost per metre and careful distribution and maintenance to ensure maximum life.

Jan 1, 1985

This paper describes a plant built at The Broken Hill Associated Smelters, Port Pirie to sample lead sinter automatically. As the plant is still in the commissioning stage results on the precision and accuracy of the sampling are not yet available, but some of the difficulties experienced during commissioning are discussed.

Jan 1, 1976

The long term viability of a mining company is dependent on the success of its capital investments. Due to the specialised nature of the design, engineering and construction of large projects the management is often contracted to an outside organisation. This paper is a review of the phases of the relationship between Client and Contractor. A rationale is developed upon which the selection of a Contractor can be made. Subsequently, the key aspects of the Client/Contractor relationship are reviewed with reference to completing the project on time within budget. The aspects discussed include Contractor management systems, qualifications of key personnel, definition of scope of work, industrial relations, project control and Contractor remuneration.

Jan 1, 1983

Gold mining commenced at Telfer in Western Australia in 1977. Ore mining was carried out by owner equipment and personnel with waste stripping by a contractor. Initial ore reserves were in predominantly high grade, geologically simple reef structures. A mining method was developed using dozers to selectively mine the ore bearing horizons with a minimum of dilution. As the mine has developed the simple, high grade ore reserves have been progressively replaced by more geologically complex, lower grade reserves. In turn, mining methods have evolved to extract this ore by the most appropriate methods. On-going attention to ore mining practices will ensure that project profitability and viable mine life are optimised.

Jan 1, 1986

By Kennedy B. J

The 1100 Orebody is the main copper production area of Isa Mine with an output of 390 000 tonnes per four week period and a work force of approximately 260 men per shift. Currently a total of 56 nippers work a three shift, five day week roster to-service crews spread over a strike length of 1000 m and a vertical height of 220 in. A variety of rail and diesel equipment provides shaftto cribroom and cribroomto sublevel work place transport of men and materials. Overall eficiency and safety has been improved with a selected group performing supply, storage, clean-up and "bus runs" throughout the orebody - activities which are further co-ordinated by an FM radio system linking units with a control clerk.

Jan 1, 1977

The use of ammonium nitrate/fuel oil explosives is.now well established in most open cut mining operations. Its use. is extending to underground mining. This has been due in a large measure to improvements in the nature of the ammonium nitrate made available from various sources. The addition of surface active agents and water in controlled amounts to the fuel oil has been found to increase the sensitivity of the ANJFO mixture with consequent better explosive properties. It is considered that the surface active agent increases the bond between the ammonium nitrate and fuel oil giving a more, intimate physical and chemical mixing of the oxidising and reducing agent. This results in increased sensitivity and a faster rate of reaction. The increase in sensitivity has been accomplished without any diminution of safety. Tests which demonstrate the safety of this type of explosive are given in the appenuix.

Jan 1, 1964

By S Totsuka, P Ortiz, E Prokkola

Electrochemical polarisation techniques can be successively applied to maintain clean surfaces in process environments. The applications are the result of extensive knowledge of the electrochemical nature of process environments, an innovative approach to problem solving and shared æcan doÆ attitudes between the supplier and process owner. Initial identification of suitable applications is based on over 20 years of process and electrochemical experience. The technologies discussed in this paper include Electrochemical Anti-Scaling [EAS], Electrochemical Protection Systems with both anodic [EPSA] and cathodic [EPSC] protection and Electrochemical Flocculation [EF]. Examples of industrial applications are reviewed. Good examples of metallurgical processes which can benefit greatly from an advanced electrochemical treatment are the wet processes involving precipitation, crystallisation and evaporation. Eliminating corrosion and scaling which would otherwise cause process disruptions and quality problems can make a big difference in process profitability. Clear advantages in both cost efficiency and environment friendliness are easily demonstrated. Continuous processing with minimum downtime is one clear advantage. In comparison to the use of corrosion inhibitors, anti-scaling agents and flocculants, the electrochemical polarisation does not increase the environmental load from the process as no additives of any kind are used. In most cases the cost benefits from pro-actively keeping surfaces clean with the help of advanced electrochemistry are substantial when compared to traditional re-active methods and other active treatments.

Jan 1, 2004

As I drove in from the airport on Sunday somebody said `On the right you will see Dun- troon, which is the military training school of Australia.' So I asked the driver, where did they get that name? `Oh,' he said, `from some people who built a house there. That was it's name- Duntroon.' It strikes a note with me because, that's the name of a 12th century castle on the west coast of Scotland where I spend what leisure hours I have and, therefore, it establishes the long connection between Australia and my native land. There is also a story I should tell you about the oil industry and its upsurge in Scotland recently which has resulted in great prosperity. And in Edinburgh, the walls of the banks are bulging-because of the incursion of foreign exchange and other resources.

Jan 1, 1978

By Kim M

Mukuk gold mine in South Korea produces a pyrite concentrate containing gold associated with arsenopyrite as a gangue mineral. The effects of Portland cement as a depressant on the flotability of arsenopyrite were studied to improve the separation of arsenopyrite from pyrite concentrate containing gold. A series of the fundamental flotation tests were performed using Portland cement as a function of pH and concentration of the collector. Flotation recovery of pyrite and arsenopyrite in the fundamental tests with amyl xanthate showed that arsenopyrite was depressed by the addition of a moderate amount of Portland cement, but pyrite was not depressed by it. In the flotation tests of the artificial mixture samples with arsenopyrite and pyrite, following pH were adjusted to be 10.5 by Portland cement, different amount of amyl xanthate was added. The results from these studies showed that flotation recovery of pyrite was 100 per cent under the condition of some addition of amyl xanthate, but arsenopyrite was not floating at all. Portland cement shows remarkable depression of galena, but its effect on the flotability of chalcopyrite is not as clear. In the pulp under Portland cement addition, chalcopyrite can be easily activated by the addition of sodium bisulphite, whereas galena is depressed more effectively. From the batch flotation tests with the pyrite concentrate, the galena concentrate and the Cu-Pb bulk concentrate from the mines, it was confirmed that the results of the batch flotation tests agree with the results of the fundamental flotation tests. The effects of depression by Portland cement on pyrrhotite, marmatite and stibnite are also discussed briefly.

Jan 1, 1993

North Broken Hill Limited came into prominence as a producing mine at· the commencement of the present century, when a great many of the disabilities experienced in earlier mining operations th:rough lack of adequate stope filling had been overcome.The northern or narrower ore-body was first mined in the upper levels and, in the early stages, no great difficulty in mining was experienced. In depth, under the influence of its northerly pitch,. the wide southern ore-body entered the North mine between the 400 and 500-ft. levels. Owing to its flat dip and the relatively weak nature of the hanging wall and footwall, the value of close filling was recognized and this policy has been followed throughout the life of the mine. This feature undoubtedly contributed to the freedomfrom "creep" action to which some of the older mines had been subjected.The Broken Hill lead-zinc-silver ore-bodies occur as well defined replacements of favou:rable horizons, in intensely folded Pre-Cambrian sedimentaries. In the North mine two main replacement zones occur, the Gre being found where the beds are involved in a certain set of minor folds. The resulting ore-bodies are roughly elliptical in cross-section, the long axis of one being north-east of, and somewhat offset from the long axis of the other. The ore-bodies pitch eastwards at 40° and dip northwards at 60° in a fairly regularmanner. The southern Ore-body has an average length of 700 feet and an average width of 90 feet with a maximum width of 230 feet, whilst the nonhern ore-body on the lower levels averages 500 feet long and 40 feet wide.

Jan 1, 1940

The Lennard Shelf Operations owned by Western Metals Ltd evolved from the Cadjebut Zinc Lead Mine (BHP) in August 1994. Original production of 0.5 mtpa will rise to 2.0 mtpa at the end of 1998. Employees work a multiple of fly-in/fly-out (FIFO) rosters from the Kimberley region and the WA Capital. The three underground mines, treatment and services departments will employ approximately 300 people by the end of 1998. The expansion of the Lennard Shelf Operations as a remote mining location was based on a fresh look at management systems and employee rosters which were generated from many years of mining experience. This paper will endeavour to summarise these experiences and analyse some of their outcomes. Dealing with several mining methods, engineering difficulties, logistical problems and climate extremes, the Lennard Shelf Operations has managed social/employee issues with excellent results. Much time has been spent to get this correct for the Lennard ShelfÆs own set of circumstances. Employees and associated companies must expect continuing changes and improvement as Western Metals strives to continually improve its management systems and employee rosters.

Jan 1, 1998