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This paper endeavours to lay as concisely as possible, before the members the salient features of local gold milling practice, and to point out in what respects this practice differs from that of other large mining camps. This is essentially a free milling ore the gangue being quartz and the gold occurring in a coarse form. At times the ore crushed contains a good deal of slate, the latter imparting to the tailings a somewhat leaden hue.Small amounts of sulphides, chiefly iron pyrites, and at times smaller quantities of arsenical pyrites, zinc blende, and galena are contained in the stone. The average amount of sulphides contained in the ore cannot well be ascertained, as the concentrate obtained in all cases contain too much silica to form a basis of calculation...

Jan 1, 1902

By R Lewis

Drill hole magnetometric resistivity (DHMMR) is a relatively recent addition to the explorationistsÆ suite of techniques for finding further resources in the vicinity of a drill hole. The method relies on gathering of an applied current into zones which are less resistive than the country rocks and it was first applied to exploration programs looking for weakly conductive sulphides, such as, for example, carbonate-hosted zinc deposits. More recently, it has been applied to a wider range of deposit styles, including highly conductive nickel sulphides. It has been found that the technique is capable of not only detecting mineralisation not seen by conventional electromagnetic (EM) techniques, but it can detect at a greater distance. Also, whilst EM is superior at defining tabular-shaped conductors, DHMMR may be more effective at finding cigar shaped sulphides. This paper presents a number of examples illustrating these findings.

Jan 1, 2000

Development of aggregate resources for use in structural concrete has been encouraged in Japan to support infrastructure improvement and national land conservation. Natural aggregate is a valuable resource necessary for sound economic development, and its importance is growing. After completion of aggregate mining projects, planting and afforestation are implemented. But sandy soil in excavation sites is not optimum for the growth of vegetation, and many years are needed before forests are restored. Planting techniques should be improved to support efficient reforestation in a shorter period of time. For this purpose, problems hampering growth of vegetation must to be solved through application of physical and physicochemical techniques to ensure that the environment and the ecosystem will be conserved in project sites.

Dec 6, 2010

By Morgan W. M

It is not the primary object of this paper to treat with the scheme of prospecting in detail, but it is considered that a brief description of the broad lines is necessary so that the significance of the points to be discussed later may be appreciated.The finding of payable gold reefs on the Bendigo field resolves itself into a two-fold problem, firstly the location of quartz bodies, and secondly the location of gold shoots in such bodies. The country rock of the field has been folded and faulted, and the occurrence of known reefs is associated with the fold axes and the faulting. The "lines" of the field are the anticlinal axes, and practically all known reefs are at or near centre country. Very little work has been done on the synclines, which may have some potential value.Quartz has been introduced along the fracture systems, and gives rise to the three main types of reef met with on the field, namely, the "back," which is similar to a bedded quartz reef and is formed along a bedding plane fault; the "saddle," which forms at the crest of the anticline and has the typical shape from which it takes its name; and "spurs," which are irregular masses of quartz, making off reefs of the first two types.As the fracturing throughout the field is widespread and fairly intense, the first problem, that of finqing quartz, is comparatively simple, and any regular system of blocking out the ground will be productive of quartz bodies.*Field Superintendent, Bendigo Mines Ltd. Assistant Field Superintendent, Bendigo Mines Ltd.

Jan 1, 1936

The first part (lH of this work dealt with the process of recrystallization of single crystals of lead after deformation by creep, as revealed by macroscopical examination. It was shown that when recrystallization commenced, a crystal, termed the primary crystal, started to grow at the edge of the specimen and extended into the body of the specimen along the slip planes. At some stage during the growth of this crystal, other crystals appeared at the boundary of this first crystal and fragments of the parent crystal. From thispoint, recrystallization was accelerated with relatively rapid necking down of the specimen until fracture occurred.All those crystals formed after the primary crystal were given the term secondary crystals. In the present paper is given a detailed account of the orientations of the primary and secondary crystals.EXPERIMENTAL METHODThe size of the test pieces and the manner of loading were given in the previous paper (1). X-ray back reflection photographs were taken of the individual primary and secondary crystals and from them were determined the orientations. The path of the X-ray beam was perpendicular to the surface of the creep specimen.In view of the large number of photographs needed, gold...

Jan 1, 1940

By B Leisemann, M Watkinson

Coal augering is an ideal method for recovering coal from the highwalls of open cut coalmines. Coal augering is a simple process whereby additional flights are added to the auger cutting head and auger holes are drilled at 1.9 m diameter up to 200 metres deep. Traditional monitoring was located at the mouth of the hole and if methane was encountered above two per cent, inert gas was delivered into the mouth of the hole to deplete the oxygen content at the auger cutting head below 12 per cent. The auger operator was asked the question ‘how do you know that this is the case?’ Trials were undertaken to prove that the oxygen content at the cutting head did drop below 12 per cent (the lowest limit for methane to ignite, also known as the oxygen nose point). Initial trials showed that the oxygen content in the mouth of the hole did not drop below 12 per cent and modifications were made to hold the inert gases in the mouth of the hole so that the auger flights could take this inert gas into the hole. In-hole monitoring, after completion of mining and after extracting the auger flights, showed that the atmosphere quickly returned to fresh air. In-hole monitoring was also tried during the augering process and yielded valuable results. This paper will discuss the results of the monitoring, information on the gas results obtained and the methodologies used to optimise the oxygen content at the auger face.CITATION:Watkinson, M and Leisemann, B, 2017. Inertisation of coal augering holes, in Proceedings Australian Mine Vent Conference 2017, pp 293–298 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 28, 2017

The Burra Burra Mine is situated in complexly folded Torrensian dolomites and limestones forming the faulted axial region of a major anticline. The orebody mined was largely of secondary origin and confined between two faults, Kingston's on the west and Tinline's on the east. The orebody occurred at the junction between cherty dolomites and a clastic limestone with a large mass of marble breccia along its western margin. Secondary ore consisted of carbonates and oxides in the breccia and the ore bed and detrital copper minerals deposited as part of a clastic breccia in sinkholes and solution cavities in the dolomites and ore beds.Primary sulphides occur disseminated in the marble breccia and in stratiform habit in the ore bed. Kingston's so-called "lode" may be mineralized marble breccia.The marble breccia appears to be of diapiric or sedimentary origin and there is evidence to support a sedimentary origin for some of the copper sulphides. No igneous rocks have been discovered within 20 miles of the mine and any hydrothermal activities were probably at comparatively low temperature. The possibility of extensive stratiform and disseminated copper sulphide mineralization in the marble breccia and ore bed requires testing by further drilling and geophysical surveys.INTRODUCTIONThe re-interpretation of Burra Burra geology and ore formation discussed in this paper resulted from a comprehensive investigation of the mine and its surrounding district begun in December 1961 and in progress at the time of writing. (February 1963). The decision to investigate Burra Burra was taken after a thorough examination of records and reports of all non-ferrous metal deposits throughout South Australia and was given impetus by a report by Thomson (1963) suggesting a sedimentary origin for the copper mineralization. Although the author does not concur fully with Thomson's interpretation there is no doubt that sedimentary processes have played an important part in the formation of the Burra Burra copper deposit, nor is there any doubt that igneous activity played no part.

Jan 1, 1963

GOOD ventilation is recognized as an essential for the preservation of health, and laws have accordingly been framed in many countries for the provision of adequate ventilation in factories and places of public resort as well as in mines.Apart from the legislative enforcement of hygienic measures as a matter of public 'policy, the ventilation of mines has an important economic aspect, since it affects to a large extent the industrial efficiency of the workmen, and consequently the cost of mineral production. Until recent years the ventilation of metal mines has not generally received much consideration, and the importance of pure air has been sometimes overlooked. To the absence of explosive gases in such mines, and to the cost of the installation and working of mechanical ventilators, may generally be attributed disregard of adequate ventilation. In this paper it is not proposed to furnish statistics on the mortality and morbidity of miners, or a treatise on the medical aspect of the rock-dust problem, to further elaborate which would be superfluous, the deleterious effects of the latter having been...

Jan 1, 1912

A subsurface study of the Maria Lode and associated hydrothermal alteration of andesites within the Karangahake epithermal gold-silver deposit defined the local evolutionary sequence in the once active geothermal system.   Some implications for mining of epithermal deposits arise as a result.

Jan 1, 1984

The Beckman Air Comparison Pycnometer is as accurate as the specific gravity bottle for the determination of the volume of fine powders, or particles, up to 50 c.c. in volume. The determination using the air comparison pycnometer is performed in a much shorter time.A graph of density versus iron content for samples from four different iron ore deposits shows that iron contents can be obtained to within 4 per cent iron. Field geologists should be able to obtain quick and relatively accurate iron contents of ore samples using the air comparison pycnometer at these deposits.INTRODUCTIONA Beckman Model 930 Air Comparison Pycnometer was purchased to decrease the time required for the determination of the volume of stones and powders. The liquid displacement method was used previously and the time required per determination varied from a few minutes for stones to half an hour, or more for fine powders. With the air comparison pycnometer, the determination takes approximately 2 min and can be quickly checked for accuracy by a further determination. The total time for weighing, determining, and checking the volume is no more than 5 min.DESCRIPTION AND PRINCIPLE OF OPERATION OF PYCNOMETERDescriptionThe air comparison pycnometer measures the volume of materials, in c.c., by determining the amount of air displaced.A diagram of the main components is given in Fig. l.Cylinders A and B are equal in volume and each has a piston which is moved by turning a handwheel attached to a geared shaft. The measuring piston shaft is geared to a 5...

Jan 1, 1963

The association of deep well turbine type pumps with metal mining is by no means a new one, though undoubtedly each application has certain features of interest, conformable with attendant circumstances. Although all conditions pertaining to a particular operation in one mine are rarely, if ever, duplicated in another mine, it is felt that some aspects will be parallel, or in various ways comparable.Therefore the following descriptions of an installation of a deep well turbine pump as part of dewatering plant in connection with shaft sinking may be of general interest to metal mine operators.The Man and Supply shaft at Mount Isa Mines is designed as shown in plan by Fig. 1. It is the main entrance and service shaft for the entire property and hence is in constant use. Arrangements for sinking must be such as to cause little or no impediment to routinehoisting work. Also, being the main shaft, it has been essential to deepen it in step with successive level developments.During the period of operations at Mount Isa only a limited time has been available to complete succeeding levels down to the present No. 7 haulage level (895 ft.), and sinking operations in soft, broken, leached, and heavy water-bearing country have presented many features militating against reasonable speed and cost. Outstanding among these difficulties has been the large volume of water contained in the pervious brecciated country.

Jan 1, 1939

Gippsland has perhaps the most colourful history of exploration of any area in Australia. Hydrocarbons were first discovered in the Gippsland Basin in 1924 when a water well at Lakes Entrance encountered oil and gas shows. In 1942, the Commonwealth and Victorian Governments, in an effort to supplement a wartime oil shortage, sank a shaft near this well and produced 8000 barrels of low gravity oil up to 1956, when the field was abandoned. A total of 64 shallow wells had been drilled in the Lakes Entrance area by that time. Elsewhere in the onshore Gippsland Basin, 30 wells were drilled from 1925 to 1941. In 1960 BHP Ltd was granted an exploration permit covering much of the offshore area of the Gippsland Basin. Esso Australia Ltd joined BHP in 1964 and drilled the Barracouta-1 gas discovery in 1965. Since then over 100 exploration and appraisal wells have been drilled in the basin resulting in the discovery to date of some 3.6 billion barrels of recoverable oil and 8.8 trillion cubic feet of recoverable gas (Current remaining recoverable reserves are 906 million barrels of oil and 5.7 TCF of gas). Exploration in the offshore areas is actively continuing today and new discoveries are still being made.

Jan 1, 1992

A study of the swelling behaviour of a single batch of high-grade iron ore pellets during hydrogen reduction in a fixed bed showed that the extent of swelling is governed by the nucleation and growth of crystalline iron protuberances from the wüstite grains. Over the reduction temperature range 650 to 1000°C, it was found that substantial degrees of swelling can occur at temperatures in excess of 850°C, and significant variations in the swelling behaviour of individual pellets from different bed levels are observed under these conditions.The results are discussed in terms of a recent swelling theory and shown to be in general agreement.

Jan 1, 1978

By Burns K. L

Keyboard patterns of hundreds of minor faults with vertical displacements of 3 mm to 2 m occur within the Greta coal seam and cause serious mining problems in collieries. Many of the faults are concentrated in linear zones termed swarms. One swarm is 600 m wide and more than 800 m long and others are of comparable size.The minor faults between the swarms are normal and are relatively widely spaced and show dip-slip movements, but the faults within a swarm are clustered and show strike-slip and oblique-slip movements. Fault swarms ofthis size and frequency have not previously been described from the Sydney Basin or on a comparable scale elsewhere but appear to be a widespread phenomenon in Australian coalfields. The faults are assigned to classes onthe basis of orientation which are then assigned to sequential phases I to IV on the basis of offsetting relations between representatives of each class. Phase I faults are minor thrusts. Phase IT, Ill, and IV faults are concentratedin the swarms and show sinistral strike-slip and normal dip-slip movements. The interference of slickenlines indicates that multiple movements have occurred within a single phase; their order is (i) strike slip (ii) dip slip and (iii) oblique slip. All faults truncate and post-date both cleat and sedimentary "stone" dykes.Phase I minor thrusts trend at a high angle to the Hunter Thrust and are considered to predate the Late Permian movements on the Hunter Thrust. Phase II and III minor faults are younger and may be any age between the latePermian and Tertiary.

Jan 1, 1978

Exploration work at the southern flank of the Mt. Coffin diapir has encountered three different types of copper ores: copper carbonate, largely malachite; secondary sulphides, mainly chalcocite replacing pyrite; and a primary arsenopyrite-tennantite-tetrahedrite-chalcopyrite association. The secondary copper ore is occasionally stratiform but mainly erratic at the contact between tillites and siltstones of the Tapley Hill formation.There have been two stages of primary mineralization.1. Arsenopyrite, tennantite, and tetrahedrite occur in siderite veins.2. Revival of the diapirism has caused fracturing and local brecciation of the rimrock and subsequently ascending solutions precipitated chalcopyrite. The chalcopyrite also partly replaced arsenopyrite, tennantite, and tetrahedrite.

Jan 1, 1972

The district specially referred to in this paper comprises the very gently sloping country extending from the western shores of Port Phillip from the mouth of the Yarra to Footscray along the Bacchus Marsh railway to near that town thence in a southerly direction to the Little River, and along that river to the coast, 1 as may be seen on the accompanying map. Almost the whole of this area is covered by volcanic rocks, consisting of pumerous sheets of basalt, which have been poured out of various volcanic hills in the districts, such as Mts. Atkinson and Cotteril, near Melton; Mt. Maryand Bald Hill, 12 and 16 miles respectively N.W. of Werribee; and vents in different parts of the parishes of Tarneit, Mouyong, Mooradoranook, Pyweitjorrk, and Derrimut. These volcanoes were in an active state of eruption during a late period of the earth's historyprobably the late Pliocenll, or still younger Pleistocene.Occupying a narrow strip of country, for most of the distance along the coast from Williamstown to past the mouth of the Little River, there occur deposits of still younger age, belonging to the Recent period. These lie on the basalt, and extend for distances varying from a few chains to more than a mile back from the beach. They comprise superficial deposits of blown sand, and raised beaches, composed of marine sands...

Jan 1, 1902

Filtration of pulps of varying densities is an essential operation in the hydro-metallurgical production of zinc. The use of filters naturally applies only to the "wet" plants, and in these varying types and sizes are in commission. At Risdon, the Moore suction filter is used for the heavier pulps, except in one instance, where a modification of the Butters-Cassell filter is installed.Filter presses are in general use, and of these, one is a washing unit; the plates, and frames are of cast iron or mild steel, except in one case which is a centre feed press having wooden frames.FILTER DESIGNThe problem of filtration presented itself very early in the history of Risdon and the first developments occurred in what was termed the 250 -lb. plant. Here experiments were made with many types of filters, and as this was the pilot plant on which the design of the 10 ton plant (10 tons of zinc per day) was based, quick decisions were necessary.An Oliver type filter was chosen for the heavier pulp or residue, and a Shriver wooden frame filter press for the lighter pulps.To this day, but with a number of variations, filter presses continue to function unopposed in their particular field; however, the Oliver filter was soon superseded because it was found impossible to wash the filter cake efficiently without repulping; consequently its use was abandoned and the Moore filter adopted.Both- these filters have been modified and developed in many ways to meet the requirements of a zinc plant, but they retain their original basic features.

Jan 1, 1949

By H W. Wu, D Humphreys

The structure of a comprehensive research project into mine fires study applying the Ventgraph mine fire simulation software, preplanning of escape scenarios and general interaction with rescue responses is outlined. The project has Australian Coal Association Research Program (ACARP) funding and also relies on substantial mining company site support. This practical input from mine operators is essential and allows the approach to be introduced in the most creditable way. The effort is built around the introduction of fire simulation computer software to the Australian mining industry and the consequent modelling of fire scenarios in selected different mine layouts. Application of the simulation software package to the changing mine layouts requires experience to achieve realistic outcomes. Most Australian mines of size currently use a ventilation network simulation program. Under the project a small subroutine has been written to transfer the input data from the existing mine ventilation network simulation program to æVentgraphÆ. This has been tested successfully. To understand fire simulation behaviour on the mine ventilation system, it is necessary to understood the possible effects of mine fires on various mine ventilation systems correctly first. Case studies demonstrating the possible effects of fires on some typical Australian coal mine ventilation circuits have been examined. The situation in which there is some gas make at the face and effects with fire have also been developed to emphasise how unstable and dangerous situations may arise. The primary objective of the part of the study described in this paper is to use mine fire simulation software to gain better understanding of how spontaneous combustion initiated fires can interact with the complex ventilation behaviour underground during a substantial fire. It focuses on the simulation of spontaneous combustion sourced heatings that develop into open fires. Further, it examines ventilation behaviour effects of spontaneous combustion initiated pillar fires and examines the difficulties these can be present if a ventilation reversal occurs. It also briefly examines simulation of use of the inertisation to assist in mine recovery. Mine fires are recognised across the world as a major hazard issue. New approaches allowing improvement in understanding their consequences have been developed as an aid in handling this complex area.

Jan 1, 2005

In responding to why some longwall roadway development rates are different among mines, the Roadway Development Task Group (RDTG) of Australian Coal Association Research Program (ACARP) has initiated a benchmarking study to survey each longwall mine to determine the correlation between roadway development practices and roadway development performances. This paper describes a web-based relational database system which has been developed purposely to monitor the performance of Australian longwall roadway developments aimed at assessing both the physical and operational factors which could influence roadway development practices and their performance indicators. Statistical analysis of an earlier survey suggested that continuous miner units that achieved more than 1750 m were units mining two-heading development.

Dec 6, 2010

THE machine from which the following results were obtained makes one of a row of seven at work in the Junction North, Concentration Mill at Broken Hill, New South Wales. It consists essentially of a belt for dressing purposes, which travels round two 12-in drums situated at either end of a wooden frame. This frame is supported on wooden legs, and the whole is affixed to two iron castings, one on either side of the frame. A to-and-fro motion is obtained from an eccentric shaft, which, together with the stationary end of the supporting legs, is carried by the iron castings. A belt drive to the forward drum provides a constant rate of travel to the dressing belt.The top half of the dressing belt is supported on 3-in rollers spaced about 12-in centres along the frame of the vanner. A fairly thick dressing belt is used, and no trouble whatever is experienced from the formation of gutters between the rollers.These belts are 28 ft 4 in long, 4 ft wide, 3-16 in thick, and are made of two-ply 32-oz duck, with a coating of rubber on either side. The surface available for dressing is about 10 ft 6 in x 3 ft 8 in- ie, about 38'5 square feet. The machine is driven atthe rate of 245 i-in strokes per minute, while the dressing belt travels at 15 feet per minute...

Jan 1, 1909