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Ferruginous manganese deposits have been known at Ripon Hills since the late 1950s. The main group of deposits occur in an area 6 km by 5 km and these were extensively investigated by Longreach Metals N.L. during1971 and 1972 for possible commercial exploitation.Ripon Hills is a dissectcd fault plateau 350 m above sea level formed by the uplift of a block of gently dipping Proterozoic shales, cherts, and dolomite. The plateau consists of chert breccia which is underlain by massive dolomite. The shales which are ferruginous and manganiferous overlie the chert breccia but are now only preserved, in places, in the broad depression and valleys of the plateau.The ore deposits occur as supergene replacement of the shales and were investigated by geological mapping, grid percussion and diamond drilling, and bulk beneficiation testing. Iron and manganese oxides erraticallyreplace Shale accompanied by the leaching of other minerals. The ore is composed of fine grained pyrolusite intergrown with fine grained hematite and locally containing extensively altered bixbyite and braunite. Thegangue mineral is mainly kaolin.The average grade, using a 15 per cent Mn cutoff, was 19 4 per cent Mn and 25·9 per cent Fe for a combined drill-proven, indicated, and inferred tonnage of 56,000,000 tonnes. The average depth of this mineralization from the surface is 11 m. Using a cutoff grade of 20 per cent Mn the average grade was 24·6 per cent Mn and 23·0 per cent Fe for a combined tonnage of 12,000,000 tonnes to an average depth of 8 m.The substantial drop in reserves occurs because a high proportion of the mineralized material contains less than 20 per cent Mn.It was shown that whereas the lower grade ore, despite erratic fluctuations in grade, could be beneficiated to specification grade by crushing, screening, and conductivity ore sorting, the higher grade ore could be beneficiatedto specification grade by crushing and screening only. The utilization of the higher grade ore was considered to constitute a more viable operation.There is potential for high grade manganese ore to be discovered in the Ripon Hills area at the contact of chert breccia and underlying dolomite.

Jan 1, 1977

By Prosser A. P

The conditions under which vanadium is rendered insoluble by silica in the alkali-roast process have been investigated starting with both slag and reagent-grade materials. The inert phase is a glass formed slowlyfrom soluble NaV03 produced at lower temperatures. It contains approximately 30 per cent V in a partly reduced state; iron is not a principal component. Some of the vanadium in the inert phase is slowly returned to a soluble form by heating in an oxidizing atmosphere below the temperature at which the glass is formed (750°C). As the reaction leading to the required, soluble form of vanadium is also slow between 600 and 750° optimization and control of the temperature profile and atmosphere in the furnace, and the residence time of the solids, are necessary to ensure high vanadium extraction during subsequent leaching.

Jan 1, 1976

Ore samples generally require preparation before analysis. Serious problems can occur with contamination degradation and particle size effects. Both grinding element contammation and sample cross contamination havebeen bound to be related to sample hardness and operator technique. For best results with minerals relevant to the steel industry, the use of Siebtechnik-type mills required a combination of careful planning, short grinding periods and intermediate sieving of the sample. The results may be extended to most mineral, rock, and refractory sample preparabons.

Jan 1, 1978

The published liquidus data on the Pb-PbS system have been correlated on the basis of one-coefficient Margules equations. Thermodynamic properties of the components of this system have been obtained, and it has also been found that the calculated miscibility gap of this system exists over a very narrow range of temperature (1041 to 1058°C).

Jan 1, 1972

In presenting this paper the author has in view a twofold purpose. In the first place, it is intended to set forth for the benefit of practical mining men some account of the principles underlying the design of tungsten carbide rock bits in the hope that a knowledge of these principles will assist in the successful application of the bits to mine and quarry drilling. Secondly, by evoking discussion, and even controversy, it is hoped that manufacturers and users of these rock bits will be encouraged to contribute to the general knowledge of a subject which to date has been rather lacking in published literature. The author well appreciates that many of the conclusions drawn in this paper are highly controversial, but if the only result is to call forth contradictory testimony from other workers in this field, at least one of his purposes will have been achieved.An attempt will first be made to set forth and examine those characteristics which go to make up an efficient rock bit, and the main factors affecting these characteristics will be discussed. In a paper of this general nature, consideration of any particular aspect must necessarily be rather brief, and there is little opportunity for detailed presentation of test procedures and data. Thus, it has been found advisable' to confine discussion of some minor points to a simple statement of fact. However, an attempt has been made to support all major conclusions by reference...

Jan 1, 1950

The Stawell Goldfield, the westernmost of the main Victorian fields, has produced over a million and a quarter ounces of gold from one and three-quarter million tons of ore. The lodes are quartz reefs and sulphide bodies occurring in sediments of lower Ordovician or upper Cambrian age. The lodes are confined to a relatively narrow suite of weak rocks lying between stronger ones above and below and there is a definite relationship between fold structure, pitch and strength of folding and ore.LOCATION HISTORY AND PAST PRODUCTIONThe town of Stawell, situated 150 miles north-westerly from Melbourne on the main railway and road to Adelaide, is the most westerly of the main gold areas of Victoria. Alluvial gold was found at Pleasant Creek (now Stawell West) in 1853 and the usual "rush" followed. Numerous alluvial leads, some surface, others buried under up to 100 ft. of Tertiary sediments were worked. The alluvial gold was soon exhausted, but in 1857 gold-bearing reefs were found on the slopes of a prominent ridge on the northern edgeof the present town. Early reef mining was by small working parties mining to shallow depths only and treating their ore at public crushing plants. Some of the early returns were very high grade. The next stage was the amalgamation of claims and the formation of companies, with their own treatment plants. This stage continued till the last mine closed in 1921. These companies had, by present standards, small holdings and far too many shafts were sunk, resulting in less efficient prospecting and operation.Since 1921 there have been one or two small scale attempts to revive mining but without success. Of recent years Gold...

Jan 1, 1960

As a result of the world depression and the consequent heavy fall in the price of tin, Malaya joined with other great tin producing: countries of the world in a restriction scheme that heavily restricted production from its individual mines. This condition, together with the knowledge that it was becoming more and more difficult in, Malaya to acquire further areas and so prolong the existence of a specific company's activities, induced Mr. H. G. Scott, managing director for the Siamese Tin Syndicate Ltd., to consider other possible sources of production. Mainly because of the conditions that obtained in Tasmania, he turned his attention to that country, where, not only could mining be carried on without restriction as to output, but where the incidence of the exchange position created favourable conditions for operation. The district selected for examination was that of St. Helens, on the East Coast of Tasmania, which district had behind it a long record of successful tin mining operations.PRELIMINARY OPERATIONS OF SIAMESE TIN SYNDICATE LTD. AT ST. HELENS.First of all the district was examined, and there was no lack of evidence to show that tin existed, although it was impossible to get down to quantities and values without an extensive prospecting campaign. For one thing, the physical features of the country seemed to be all wrong. There were no extensive alluvial flats such as a mining engineer...

Jan 1, 1934

By Wilson D, Kirkland J

Compressed air energy storage (CAES) uses low cost off-peak energy to compress air and pump it into pressurised underground storage. Expanding the air through a modified form of gas turbine generates electrical energy when required. While generating power, a CAES station consumes approximately one-third of the gas required for the equivalent installed capacity of a conventional gas turbine. Air can be stored in underground rock caverns, caverns in salt domes, or in aquifers. Existing CAES power stations use caverns mined out of salt domes. Aquifer storage for CAES has been proposed, but not yet implemented. The groundwater in the aquifer would be displaced during air injection and when required the air would be extracted using the natural hydro-static pressure. Victoria has no salt domes, but has aquifers onshore in the Gippsland Basin with geological dome structures of suitable depth, discovery pressure, porosity, permeability and caprock for CAES development. Field tests costing several million dollars would be required to prove the suitability. The most suitable aquifer is near Seaspray, where several dome structures exist. The aquifer, comprising of coarse sands capped by coal and mudstone, is some 600 metres deep with a hydrostatic pressure of 6.3 MPa. Computer simulation of injection and extraction of air from the aquifer under various combinations of horizontal and vertical wells, permeability and tubing head pressures indicated the largest aquifer structure had the capacity to sustain a 300 MW station. A well field comprising of 24 directionally driven wells with a horizontal exposure to the aquifer would achieve the air flow rates required. Using plant similar to that recently installed at McIntosh Alabama USA, would mean high capital costs compared to standard gas turbine plant. However, a review of modem gas turbines indicated that they could be easily and economically adaptated to CAES duty. Adapting a 120 MW gas turbine would give 344 MW output. A separate air compression plant would be used. Economic evaluations indicate that, for gas prices above $1.95 per GJ, a 344 MW CAES plant is more economic for intermediate/reserve load duty than simple cycle gas turbines.

Jan 1, 1992

The author summarizes and extends the relevant results of papers previously published by various authors and presents these results in chart form. The charts are used to demonstrate the theory on a hypothetical mine.INTRODUCTIONRecently a series of articles have dealt with leakage in a mine ventilation system and the problem of its reduction.Theories were developed by Peascod and Keane (1955) for the combined effect of flow in the airways and leakage through the porous barrier between the intake and return of an ideal mine. Later Keane and Peascoa. (1956) extended these ideas to the use of an underground booster fan in increasing the face ventilation and showed how to determine the water gauge and location of the most efficient underground fan.These articles were based on the assumption that Atkin:son's formula:P = R Q2 (1)gave the relation between the pressure drop P lb'/sq. ft., the quantity, Q kilocusecs, flowing in the mine airways and the total resistance, R Atkinsons, to air flow offered by the mine roadway. An Atkinson is defined as a resistance such that 1 kilocusec of air flows due to a pressure drop of 1Ib.jsq. ft. However for conditions prevailing in most mines a more :appropriate relation is that postulated by Reynolds and others (Lamb, 1953) :P=R Qn (2)where n has some value slightly less than 2. It should be noted that Atkinsons may not be used as units when n is not equal to 2.

Jan 1, 1958

The mineral composition and microtextures of a cubanite-rich sulphide ore are described and cubanite breakdown textures are illustrated. The occurrence of cubanite in macroscopic dimensions is featured.The origin of the ore is tentatively related to a composite ore fluid arising initially from an ultramalic source and extracting some metal components from an older granite mass along the margin of which the serpentine was emplaced. Some alternative possibilities as to origin are also mentioned.

Jan 1, 1969

By M Armstrong, S J. Coward, A Galli

Mine management is often expected to make rapid evaluation decisions at different stages of projects based on limited and uncertain data. The challenge is exacerbated by having to distil technical complexity into a financial model that is usually designed to produce only one or two key indicators, eg net present value (NPV), internal rate of return (IRR). Mining is a complex environment with many sources of uncertainty ranging from sampling to economics. In order to optimise investment decision-making, an appropriately structured evaluation framework must be utilised. An evaluation framework should be designed to encapsulate and integrate the complexity across the evaluation cycle, ie sampling, resource estimation, mine planning and treatment, and financial and economic modelling. This complexity is diverse and ranges from sampling support, scale effects to understanding the impact of variability, uncertainty and flexibility on operational efficiency and economic viability. These complexities, combined with time and capital constraints, usually do not allow all facets of evaluation to be integrated into the model. The model must strike a balance between simplified estimation techniques and sufficient incorporation of aspects of the project that will make a material difference to the investment decision. This paper demonstrates the impact of the scale of measurement on the valuation of a mineral project. Comparisons are made between global estimation averages using a top-down approach and local estimates using a bottom-up approach. Three sampling campaigns were conducted on a virtual orebody to compare the relative NPV accuracies. Stochastic forward models were run on foreign exchange rates and are compared with the results from a fixed foreign exchange rate model.

Jan 1, 2006

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

FREQUENTLY the Survey Department is caIled upon to estimate the quantity of material in various dumps, dams piles, etc... and in the carrying out of this work various methods may be employed.The method used will vary according to the particular case in hand, and factors such as accessibility of the top of the dump, steepness of its sides, height, and the condition of the material to be estimated. A certain amount of "give and take" must be adopted in the treatment of small local cavities and mounds.In all cases it is desirable that the surveys made should be tied on to the lease surveys for the purpose of location, and that all levels should be reduced to the mine datum. It is also desirable to obtain levels of the original surface before deposition of the material to be estimated. If these have not been obtained beforehand, levels and transfers round the top will be the next best. If space is availabIe, flat surface is chosen as a site for the dump, etc. This is of the utmost importance in those cases where the material will have to be...

Jan 1, 1925

Mr. Chairman, distinguished guests, ladies and gentlemen. Thank you for asking me to your conference, with its most fundamental and appropriate topic of 'Investment in Mining'. I must confess at the outset that I am one of those Australians who has rarely visited your fair land of New Zealand. This is in fact only my third visit, with all three related to Institute Conferences, and all much too brief. In so many ways your country provides a counterpoise to ours, despite the obvious disparities in size and population. And I am not only referring to the Bledisloe Cup! We would certainly each be much more lonely without the other, in this strange long-lost corner of the globe û if globes can have corners. Such an important factor in common in our shared heritages has been the mineral industry we have won from our alluvials and our rocks û especially for gold. So much of the major mineral developments which have supplied the world's appetite for metals and fuels in the past two hundred years has come from the countries settled in that period by people from Europe, especially those from the British Isles. So much of the technology for mineral and metal extraction has come from the skills of those people in New Zealand and Australia. And so much of the further development of metal processing and manufacturing of productive equipment has come from those people and from their cousins throughout the world. It is, I believe, a fair question to ask why we have failed to build on those early and considerable successes, and why we have in so many ways apparently been so content to allow others to add value to our raw materials, and to take our technological developments on to levels far beyond those that our domestic markets could sustain.

Jan 1, 1988

This paper presents the near-field rock damage owing to production blasting in limestone quarry in the western region of Japan. The study's purpose is to learn the mechanism of crack development due to blast vibration. In this study, blast vibration's magnitude was expressed with peak particle velocity (PPV) which was obtained based on seismographs recorded database. In attempt to pursue a research's purpose of this study, there were two considerable interests: near-field blast vibration propagation and prediction, and crack observed and prediction. Furthermore, with regards to considerable interest of the study, there were three essential aspects which were challenged, such as: monitoring and interpretation of seismic wave propagation in a rock mass near large explosive charge of production blast scale, measurement of blast rock damage in adjacent to blasthole, and determine critical value of PPV which may produce significant rock damage. In order to determine precision critical PPV, understanding correlation between rock damage with vibration level is firstly important to be done. This paper also discusses how to measure, detect and quantify near-field blast vibration and blast rock damage in adjacent to blasthole.

Dec 6, 2010

By I Thin, L Morizzi, C Seymour, G Mungur

Olympic Dam has been investigating mine design options for the South Mine Area (SMA), which will continue using the existing sublevel open stoping (SLOS) method. The SMA is an undeveloped mining area, located south of the existing underground mining areas currently in production at Olympic Dam. The SMA study reached the stage where geotechnical inputs were required for stope design, infrastructure location and ground support forecasts. A large database of geotechnical data was collected to inform open pit designs for the ODX (Olympic Dam expansion) project (resulting from 659 drill holes). This geotechnical data has since been reprocessed to align with design inputs required for the SLOS mining method. The result has been the construction of a preliminary three-dimensional mining rock mass model (MRMM) that has been incorporated into preliminary stope mine design and infrastructure layout assessments, which have taken into account the predicted prevailing ground conditions.As with any model, it is necessary to improve the confidence in its predictability; therefore the model must be calibrated. The preliminary SMA MRMM was no exception. First pass calibration was possible with results from underground geotechnical window mapping from exposed rock mass conditions in the lateral development and surface geotechnical holes for ventilation shafts.The SMA project continues to advance and has started a program of resource drilling. Selected holes have been identified that target data limited areas. This will ensure that the data gaps are infilled in order to maintain the required data density required to improve the model confidence. In addition, further underground window mapping in the SMA will provide ‘mine scale drill hole’ data that can be used to either update the MRMM or as part of planned future calibration. Stope performance data from stopes will provide further valuable data for calibration purposes.The proposed paper will present the process and findings that have been followed in order to establish a well calibrated geotechnical model that can be used with an acceptable level of confidence in the ongoing refinements of the mine design and planning process for the SMA.CITATION:Thin, I, Morizzi, L, Mungur, G and Seymour, C, 2016. Building and calibration of a geotechnical model for sublevel open stope design at Olympic Dam, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 523–532 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

The variation of carbon monoxide and hydrogen utilization with the amount of the reductant in the blast furnace bosh gas was investigated for the No. 4 blast furnace at The Broken Hill Proprietary Co. Ltd.iron and steel works. Newcastle. The degree of CO utilization decreased with increasing CO in the bosh gas; the H., utilization increased with the H., content of the gas. Empirical relationships for CO and H., utilization are proposed.H2, is 3-6 times as effective a reductant as CO at present levels of CO (34-39 per cent) and H2 (6-10 per cent) in blast furnace bosh gas. H2, gas injection into the blast furnace is proposed as a means of lowering the coke consumption, and the economics of H2 injection are evaluated.

Jan 1, 1975

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

Ore from the Hill 50 Gold Mine, consists essentially of pyrrhotite, with minor amounts of pyrite, chalcopyrite, galena and gold, replacing "jaspilite." The gold is associated with the sulphides as shotty particles. About 8 per cent. of the particles are less than '0.010'mm.The Hill 50 Gold Mine, at Boogardie in the Murchison goldfield, about 300 miles north-west of Kalgoorlie, was first operated in 1898. From 1898 to 1917 it yielded 20,000 short tons of ore for a recovery of 6,225' fine oz. gold, equivalent to a recovery grade of 6.22 dwt. gold per ton.The present company since the beginning of its operations in September 1936 to June 30, 1954, produced 811,081 short tons of ore for a recovery of 242,554 fine oz. of gold, equivalent to a recovery grade of 5.98 dwt. gold per ton.The grade of ore (recovery grade) has shown a remarkable variation with depth. From the 120 ft. Ievel to the 300 ft. level, it averaged about 7.5 dwt. Au per ton. Below the 300 ft. level it declined, and from 300 ft. to 400 ft. averaged 4.9 dwt. per ton, falling further with increasing depth to about 4.5 dwt. per ton at the '600 ft. level.On the 820 ft. level the grade improved sharply to about 14 dwt: per ton, and this grade has persisted down to and on the 1060 ft. level.The orebody has been described by Finucane (1953) as a series of lenses of finely banded jaspilite conformably enclosed by greenstones. The jaspilite is tightly folded and faulted and intruded by dykes of felspar porpnyry.Mineralization is practically restricted to the jaspilite.

Jan 1, 1955

SEVERAL serious accidents, which had occurred owing to the platman leaving the plat without first withdrawing the "chairs" from the shaft, set the writer scheming to devise a mechanically operated system which would obviate such accidents and be "fool-proof". It was obvious at the outset that some means of indicating to the engine-driver by the movement of the "chairs" themselves, whether they were "in" or "out" of the shaft, was necessary.An arrangement of signalling similar to railway semaphores was considered, but was rejected owing to the difficulties accruing from the large number of communicating wires which would be required down the shaft-viz., 2 for each level. After several experiments, a comparatively simple and efficient electrical system was devised, and which is covered by Commonwealth Patent TO. 10,402.One of the chief features of the apparatus is its simplicity, and its strongest point is the fact that both the engine-driver and platman receive visual indication of the position of the "chairs." The arrangement consists of a miniature coloured glow lamp, one for each level of each shaft compartment, arranged and placed beside the numbers and arrows corresponding to the various levels, on the winding engine indicators. Also a large indicating glow lamp is installed at each compartment in the various levels, in proximity to the levers for operating the "chairs." Upon operating the various levers for the "chairs," an electrical current...

Jan 1, 1909