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Cadmium occurs in the Broken Hill Lode essentially as a camouflaged element, substituting diadochically for zinc in the sphalerite.Analyses of a series of zinc concentrate flotation products, prepared from samples of ore taken at intervals throughout the developed lengths of the several orebodies forming the lode, have revealed a pattern in the distribution of cadmium relative to zinc. This pattern appears to reflect the temperature and order of deposition of the several orebodies, and the direction of movement of the mineralizing solutions.INTRODUCTIONThis investigation into the distribution of cadmium in the several orebodies of the Broken Hill lode was undertaken by the Mineragraphic Section. of C.S.I.R.O. in conjunction with the Broken Hill Geological Research Committee, as part of a study of Broken Hill mineralization.It arose from the examination of cadmium and zinc assays supplied by Mr. T. A. Read, Chief Metallurgist of the Broken Hill South Ltd.; of experimental zinc concentrates prepared from localized samples of the No, 2 and No. 3 orebodies in the Broken Hill South Mine. These assays suggested that the two orebodies were characterized by distinctive ZnjCd ratios.In view of the possible sigmficanc'e of such a difference, comparable data were sought from each of the other mines. The necessary samples of ore were collected by the geological staffs of the several mines. The preparation of separate zinc concentrates and lead concentrates from these samples, and their assaying, was conducted by Mr. Evan Hardy, for the North Broken Hill Mine, and its assodated leases, and by Mr. D., Swan, under the direction of Dr. J. C. Nixon, for the Zinc Corporation and New Broken Hill Consolidated Mines. Additional tests on the Broken Hill South Mine were made by Mr. C. W. Reilly, under the direction of Mr. T. A. Read. The samples were...

Jan 1, 1955

At the present time this plant is treating by direct cyanidation 1,000 tons of ore from Open Cut mining and dumps, and 1,200 tons of current flotation tailing obtained from the Sulphide Mill, per day.The following table shows the average analysis of the two feed products (see Table 1):Precipitation Process.-The pregnant solution obtained by the cyanidation of the above has the following general analysis:-Gold 0·600 dwt. per tonTotal Cyanide 0·050 %Free Cyanide 0·045 %Calcium Oxide 0·015 %KCNS 0·060 %Na2S20S 0·140 %CaS04 0·200 %Cu 0·050 %Zn 0·004 0/0K4Fe (CN) 6 NilThis solution, after standard clarification, is precipitated by means of zinc dust and a soluble lead salt.

Jan 1, 1939

At an early stage of the examination of most prospects, samples are taken; and the sample values obtained play an important part in determining the subsequent history of the prospect. It is, therefore, important that. eveJJy effort should be made to interpret asfully as possible the meaning of the observed results. In this connection, it is suggested that examination of the assay values of mine samples by simple statistical methods may bring to light information of considerable value, which might otherwise be missed.Although expert statisticians may derive more information from the available data, those who are, like the writer, less proficient mathematically, may also benefit by applying quite simple statistical methods. At least they will develop a useful habit of thought bywhich they become aware at all times that sampling results only provide estimates of the truth, but that an assessment of the precision of such results may be possible. The object of this paper is to provide some evidence of. the truth of these statements, by theuse of a few very elementary statistical calculations.General.The idea that any mine sample is subject to error from a variety of causes is a very familiar one. Doubt always exists with regard to the representativeness of a perfectly cut sample, and other errors may arise through imperfections of sample cutting, crushing, splitting and assaying. Some causes of error may give rise to "constant" errors, others may cause variable but one-sided "systematic" errors, and others again may bring about variable results without any tendency toward bias on the average. In statistical language, mine sample values are subject to errors which may have either assignable causes or chance causes. The former are those which can be isolated, or should be capable of isolation, while the latter are those remaining when all assignable causes have been removed. A single constant assignable cause brings about bias in all results, and one or more than one variable assignable cause brings about variation between individual results and perhaps an overall bias. The system of chance causes that would remain if all assignable causes were removed would cause variation between individual results but no overall bias. There is no sharp practical line of distinction between the two types of cause) of error; nor is it ever possible by any method of statistical analysis to be certain that there are no assign...

Jan 1, 1950

By Keet B. A, Waid J. S

The Gippsland Basin is one of Australia's most important producers of petroleum products. An inevitable byproduct of the production, refinement and transport of the millions of barrels of oil is thousands of tonnes of waste. These wastes are generated from the wellhead through to the petrol bowser and range from oily brines and coal tars to oil and petrol contaminated soils. The vast majority of these wastes are of a relatively low toxicity and most importantly are carbon-based and biodegradable. Current disposal practices tend to ignore the latter characteristic and inappropriate and/or expensive waste disposal solutions such as landfilling (tipping), incineration or ocean outfalls are the result. A very cost effective and environmentally friendly alternative is land treatment of such wastes. Landfarming, as it is called, has been successfully practiced in Europe for over a decade. Essential features of the system are: ò Application of a predetermined quantity of biodegradable waste in liquid, sludge or highly contaminated soil form, to pre-ploughed soil with concurrent addition of nutrients (N, P and trace elements) and lime to encourage bacterial activity. ò Harmless bacteria already present within the soil break down the carbon-based compounds into carbon dioxide, water and waste heat, WHILE concurrently generating new cells. The breakdown occurs over a period of weeks to months and continues with time with the extremely low levels of the more difficult waste types being the last to disappear. ò Further waste is applied to the soil at regular intervals. The treatment area may be dedicated to landfarming or may be used alternatively for agricultural purposes. Application rates vary but may be as high as 800 tonnes per hectare per year for wastes such as refinery sludges.

Jan 1, 1992

Copper ores are widespread through the Lachlan Geosyncline in New South Wales, but the size of the orebodies is generally small. The largest deposits occur in the Cobar district where an iron-rich copper ore type has been developed in Silurian sediments. Similar de- . posits to the south in the Nymagee-Mt. Hope-Melrose districts are related to quartz feldspar porphyries of probable Upper Silurian age. Deposits to the east in the Tottenham-Girilambone districts are less complex mineralogically and are possibly related to an ultra-basic source.Copper mineralization in the Highlands further to the east is often developed in Ordovician andesite or MiddleUpper Silurian acid volcanic sequences. The deposits in andesite contain considerably less galena than those in the acid extrusives; a small proportion of the mineralization in the latter has texture, mineralogy, and geologic setting analogous to the Captain's Flat copper-Iead-zinc deposit, for which both syngenetic and epigenetic origins have been proposed. Very little copper mineralization occurs within granitic material, even though rocks of this type ranging from Silurian to Carboniferous in age crop out through much of the geosyncline, and the extent of the metal contribution from plutons to the deposits in volcanics is open to question. Numerous deposits are known in the contact zone around Mid-Devonian and Mid-Carboniferous granites, however, and the formation of these orebodies has undoubtedly been influenced by plutonic activity. Small occurrences of copper with associated minor nickel sulphides are developed in a narrow serpentinite belt of possible Lower-Middle Devonian age in the southern section of the Highlands.

Jan 1, 1970

The importance of reducing the moisture content of fine coal, the nature of the retained water, and the means of its removal are discussed. A statistical technique, using a balanced block design, was used to isolate the significant factors determining water content of a coal filter cake. The most significant factor was particle size distribution. A simplex evolutionary operation (evop) was used to determine the optimal quantities of additives required to produce the lowest moisture content for a selected coal size. For this optimum condition (18·6 Ib H20 per lOO Ib dry coal), additions of 0·045 Ib magnesium ion, 0·0026 lb Separan AP30, and 0·098 Ib Aerosol OT, per lOO Ib dry coal were required. The work illustrated the uses of a statistical evop technique for the determination of optimal conditions in industrial research projects.

Jan 1, 1970

Recovery of Fine Gold Particles from Philippine Gold Deposits by Enhanced Gravity Concentration and Flotation The objective of the study is to determine the applicability of enhanced gravity concentration (EGC) and flotation for gold recovery. While gravity concentration methods have long been applied to gold ores, especially to free-milling types that requires minimal beneficiation, flotation for gold recovery has not yet taken hold as a major operation in the Philippine setting. In this study, the application of EGC and flotation for gold is applied and compared to the existing methods for gold recovery. Two samples, with assays of 7.315 and 5.333 g Au/MT (samples 1 and 2, respectively) are used for this study. These samples are subjected to mineralogical studies and is found to have a gold-particle size ranging 10 to 200 microns. To verify the separation size, the mesh-of-grind (MOG) is used as the primary parameter for experimentation. Initially, the samples are stage-crushed, ground, and subjected to EGC using a Falcon SB40 Concentrator. Based on the results, the two samples showed that recovery increases with a finer MOG. The ratio of concentration (K) decreases with a finer MOG. This shows that there should be sufficient liberation of the gold values for EGC to be effective. The effect of the enhancement is to pronounce the difference in specific gravity of the minerals, promoting better separation. This is validated by the high recovery values of 86.97 per cent and 98.73 per cent exhibited respectively for samples 1 and 2 (at 54 microns). For the flotation runs, sample 2 with an average particle size of 80 per cent passing 74 microns is examined using thiocarbamate-based collectors for roughing and subsequently exhibited a recovery of 96.32 per cent. At this point, the concentration ratio (K) is noted as an important efficiency indicator for flotation process since it yielded a very low-mass and high-metal content concentrate.

Sep 13, 2010

Terramin Australia LimitedÆs Angas Lead and Zinc Mine operates in the unique and picturesque environment of Adelaide Hills, 60 km South East of the Adelaide city centre itself. The mine was granted approval for construction by the South Australian Government in April 2007 and the Process Plant was constructed and commissioned in July 2008. This paper outlines the background to the plant design and the approval process given the close proximity to the local town of Strathalbyn, with a major focus on the commissioning learnings from the Concentrator startup for future reference and a review of the operational performance of the Concentrator throughout the first year of successful production versus design and expectations.

Jan 1, 2009

The Cowarra gold mine is at latitude 36°O'S. and longitude 149°19'E. which is roughly 20 miles north-north-east of Cooma.The deposit was· originally worked towards the end of the last century, but the presence of sulphides associated with the gold in the primary zone caused cessation of work when that zone was reached.GEOLOGY AND MINERALIZATIONThe principal country rocks are sandstones and shales of Silurian and Ordovician age, both very strongly folded with structural pitches ranging from a few degrees to almost vertical. The mine proper is within Silurian rocks and the main orebody (there are several minor parallel bodies) is developed within a shear striking approximately north, dipping approximately 70° east, and ranging in width from 2 ft to 15 ft but averaging about 4 ft.This shear is impregnated with quartz and sulphides with which the gold is associated. The predominant sulphide is pyrite though pyrrhotite is commonly present in quantity.Arsenopyrite and bornite are present in smaller amounts.Stillwell (1936, 1937a, 1937b, 1938, 1941) has published five mineragraphic reports on the ore.The various levels have been mapped in detail (Figs. 1-3) and the No. 2 level plan (Fig. 1) shows the general relationship of shearing, as now indicated by mineralization, and faulting. There is no apparent connection between the fold structures and mineralization.Fig. 3 is a longitudinal projection showing the distribution of gold expressed as inch-ounces. The estimation of...

Jan 1, 1965

By G A. Ekama

This paper describes a novel system for the biological sulfate reduction (BSR) of acid mine drainage (AMD) using primary sewage sludge (PSS) as carbon source in an upflow anaerobic sludge bed (UASB) reactor configuration. A UASB reactor was operated at a temperature of 35¦C and it received PSS (1875 mg/L COD) augmented with sulfate (1500 mg/L SO42-). The experimental results indicate that a high treatment efficiency was achieved at more than 90 per cent sulfate reduction at a liquid hydraulic retention time (HRT) of 13.5 h. In this study, the effects of various operational parameters were also investigated. The effect of a biomass recycle stream from the top to the bottom of the sludge bed was found to initiate rapid BSR from the bottom of the bed. Profile tests showed that effective and immediate sulfate reduction was achieved as soon as the influent entered the reactor. From these results, it can be concluded that the UASB configuration using PSS as energy source would be a viable method for the BSR of AMD.

Jan 1, 2009

THE slide-rule, as a quick and convenient instrument for performing approximate calculations, is steadily growing more and more into favour with the engineer, and results obtained by it are considered close enough to enable him to satisfactorily dealwith a considerable portion of his work. To the surveyor, however, whose ordinary computations must be as precise as his measurements, the present makes of rule are insufficient, except for a very narrow margin of the scales and for rough work. Few will carry the rule when they can clearly see that it is unreliable for general routine, and the careful surveyor is inclined to look askance at those who do use it, recognizing the temptation there undtmbtedly must be to push it into work that the log book should be called upon to treat. From the fact that a surveyor's duties take him on the surface in all weathers, and underground in many wet and uncomfortable places, where the manipulation of a book of mathematical tables becomes both awkward and patience-trying, an efficient slide-rule must offer the mbst transparent advantages. Again, a surveyor being specially trained to read divided scales quickly and accurately, the slide-rule must commend itself as an apt addition to his outfit.

Jan 1, 1912

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 only economically significant deposit of dolomite in New Zealand is at Mount Burnett, in north-west Nelson. The dolomite, associated with marbles and schists, is complexly deformed, and is of Paleozoic age.A very large quantity is present, although the recoverable amount is to some extent limited by the difficult terrain.Physically the quality of the dolomite is excellent. It is a tough, durable, fine grained rock. Chemically it is a little more variable. The range and frequency o~ the more important impurities are illustrated by hlstograms, as is the "dolomite factor"-a measure of the amount of the mineral dolomite in the rock. lbe dolomite factor averages 84 per cent, the remainder of the rock consisting largely of calcite. Quarrying, milling, production, and uses are described. In 1966 production reached 13,250 tons.

Jan 1, 1969

The object of this talk is to bring before members the importance of the prospector and the' State Battery system to the wealth and prosperity of the mining industry in particular and the State of Western Australia in general, and to touch on the more important features.Customs plants of any sort are usually subject to a good deal of critioism, usually on the large profits made at the expense of the customer, etc., and this often clouds the real value of the work being done.Prospectors, on the whole, are a good class of men; they work under conditions and difficulties which would deter those less spirited. Food, water and mining supplies are often difficult to obtain and frequently have to be transported great distances. Their mining tools are usually of the most primitive type, yet during last year over 109,000 tons of prospectors' ore were handled by the State Battery system for 73,250 fine oz. valued in Australian currency at over £587,000, the value being 57/- per long ton at par.This production brings the State Battery system into fourth position amongst the producers of the State, the yield being exceeded by the Lake View and Star, Wiluna and the Great Boulder.In passing I might mention that these notes were written at the end of the year 1940, and the above figures were for the previous period. The figures for last year, 1940, were not quite so good, being 101,000 tons for approximately 60,000 fine oz., valued in Australian currency at £572,000.In spite of this drop the State Battery system maintained its position as fourth in order of gold output for the State.The extractions, as a whole, throughout the system, were 92·54%, made up of 68·86% by amalgamation and 23·68% by cyanidation. These figures, for a group of 20 plants treating widely different classes of ore, must be considered satisfactory. The total production since inception is over £11,000,000 in Australian currency.State Batteries are usually more or less of a standard design. Ore is reduced to about 2i in. maximum size before being sent to the bins. Challenge automatic feeeders control the feed to each mill unit, amalgamated copper plates collect the free gold. Corduroy strakes are used with some ores after amalgamation, but in only a few cases has this been found of any advantage to the customer.The pulp from the battery is sampled, after leaving the tables, with a "Tazewell" sampler and pumped to dams for subsequent cyanide treatment.The "Tazewell" sampler is a machine driven by the moving pulp; and takes about fifteen dips per .minute from such pulp through a slotted...

Jan 1, 1941

Cobalt/tungsten mineralization at Mt. Cobalt, located 170 km southeast of Mt. Isa in northwestern Queensland, is described. Mineralization occurs in the Kuridala Formation of the Mary Kathleen Group, which is composed dominantly of pelitic schists, carbonates and acid and basic volcanics.Rocks in the region are metamorphosed to amphibolite facies and affected by two generations of tight to isoclinal folds and a third, more open generation of folds. The region is divided into three meridionally trending belts on the basis of structural style, with mineralization concentrated in the central, more highly strained belt.Deformation and metamorphism is probably younger than 1670 m.a., and the rocks are intruded by granitic rocks dated at 1509 ± 22 m.a.Mineralization occurs in shear zones at the contact between an amphibolite and enclosing pelitic schists, and within the amphibolite itself. Mineralization consists of cobaltite and scheelite with lesser chalcopyrite, pyrite, pyrrhotite, i1menite, allanite, xenotime and apatite. The mineralizing event involved addition of K, Cl, CO2 W, As, Cu, Ni, Au and rare earths and depletion of Ca and Na. It altered a hornblendeandesine/labradorite host assemblage to a biotiteoligoclase/andesine-scapolite assemblage. Though tourmalinealteration also occurs, it is probably not related to mineralization.It is concluded that the mineralization and alteration assemblages formed by reaction of saline fluids with amphibolite close to the peak of amphibolite facies metamorphism.The fluids are probably metamorphically derived, and their movement was channelled through high strain zones in the sequence. The material carried by the fluids was derived from the metasedimentary/metavolcanic pile as a whole.Other deposits in the Mt. Cobalt-Selwyn area have characteristics comparable with Mt. Cobalt, and the mechanism for the genesis of Mt. Cobalt may have applications at other areas in the region.

Jan 1, 1983

By Lewis PJ, Halfpenny R, Craighead GA

Exploration drilling by Joint Venture partners CRA Exploration Pty Ltd and Elders Mining PNG Pty Ltd has discovered a signif- icant copper and gold deposit at the Wafi River prospect, 60km WSW of Lae in Papua New Guinea. An indicated resource of 18Mt at 2.5g/t Au using a lg/t cutoff has been delineated in Zone A. No estimate has been determined for the separate copper occurr- ence at Rafferty's Zone but the copper will be significant to the project. Metallurgical studies on the gold indicate that the primary ore is refractory to direct cyanidation giving a highly variable and inadequate response. All conventional refractory ore oxidation techniques perform well on both ore and pyrite concentrate and oxidation occurs rapidly. No metallurgical studies on the copper mineralisation have been undertaken. Hypogene covellite and chalcocite copper mineralisation is associated with an intensely quartz-stockworked, and quartz and alunite-altered intrusive. Economically significant gold mineralisation occurs in distal subhorizontal lenses, within a sedimentary host, that plunge toward the intrusive. These lenses are sandwiched between overlying quartz and alunite-altered zones and underlying quartz and smectite zones in a mixed zone of quartz, dickite, kaolinite and illite alteration. The alteration and mineralisation is classified as a high sulphidation, epithermal style resulting from the influx of hot, acid magmatic fluids. Preliminary land ownership, road access, power supply and mine infrastructure studies are in progress. The project is currently at an advanced exploration stage.

Jan 1, 1991

By R L. Brathwaite

The epithermal gold-silver deposits wall poster is one in a series of posters on different mineral deposit types being produced by GNS Science to raise awareness of the characteristics of New Zealand mineral deposits and their prospectivity. Epithermal deposits consist of quartz veins, quartz vein stockworks and hydrothermal breccias that are mainly hosted in subaerial andesitic or rhyolitic rocks of Tertiary age. The deposits were formed at depths of typically less than 1 km and at temperatures between 180¦ and 320¦C, although ore grade mineralisation was generally deposited at less than 270¦C.   In New Zealand, epithermal deposits occur in association with late Cenozoic volcanic rocks in the Northland, Coromandel and Taupo volcanic regions. All of the past and present gold production, estimated at greater than 380 t (along with 1300 t Ag) comes from the Miocene-Pliocene Coromandel Volcanic Zone, where about 50 epithermal gold-silver deposits occur over a 200 km long belt. In Northland, silver and mercury have been produced from hot spring type epithermal deposits, and several gold-silver prospects have been identified. Ore grade gold-silver mineralisation is currently being deposited in several active geothermal fields of the Taupo Volcanic Zone, and extinct geothermal systems occur on the western side of the zone. The active systems have provided natural laboratories to help understand the processes of epithermal mineralisation.

Jan 1, 2005

From time to time efforts have been made to classify rocks according to their hardness, toughness and abrasiveness, and to use these classifications to provide an indication of the ease or difficulty with which they may be drilled. However, rocks classified as of similar type on this basis may vary considerably in their .resistance to the penetration of a rock drill bit due to differences in their physical state.For instance, fine grained rocks of granular texture are more difficult to drill than equivalent' rocks of coarser structure, altered rocks drill more readily than unaltered ones, and silicified rocks usually exceedingly hard and tough may be so shattered by movement as to be drilled at a rate comparable to quite soft rocks. Therefore, considerable latitude has existed in this method of defining their drillability, and no values generally acceptable have materiaJised; so that, when the drilling properties of rocks are discussed, it is common practice to refer to their hardness or toughness in a greater or lesser degree depending to some extent on the emotional state of the drill runner.REFERENCES AND STANDARDSThe 'introduction of tungsten-carbide tipped rock-drill bits for use with percussion rock-drills has thrown increasing emphasis on the need for defining a rock's resistance to penetration in a more concise and generally acceptable...

Jan 1, 1950

Fire suppression systems are now recognised by both NFPA 502 and PIARC as legitimate tools for both life protection and asset protection. The effectiveness of these tools for life protection demands extremely rapid and accurate incident detection coupled with rapid response. This rapid response must be integrated with other emergency systems such as emergency ventilation. The March 2007 fatal Burnley Tunnel incident in Australia graphically illustrates the potential of effectively integrated fixed suppression systems to protect people from harm and save infrastructure from damage. Despite the raft of technology available in that instance to the operator it was the human operatorÆs ability to effectively control the emergency equipment and not the equipment itself which so positively influenced the threat to life and property.

Jan 1, 2008

By C E. J de Ronde, I C. Wright

Oceanic subduction-related volcanic frontal arcs extend over 20 000 km within the western Pacific basin and over 21 500 km worldwide, yet they remain largely unexplored with respect to active seafloor mineralization. Systematic exploration of 26 major submarine volcanoes along ~840 km of the Kermadec arc northeast of New Zealand has documented ten (39 per cent) as being hydrothermally active. This frequency of venting is comparable to that on slow-to-moderate rate spreading mid-ocean ridges, which comprise ~80 per cent of the 60 000 km-long global system of spreading centers. The chemistry of fluids discharged from the Kermadec arc volcanoes is moderated by magmatic components in both the gaseous (CO2 + SO2-H2S) and liquid (Fe) phases at very high concentration.The high frequency of venting coupled with chemically rich discharge discovered during this first systematic survey of any arc system forecasts submarine arcs as being important sources of chemicals to the oceans and as potentially lucrative exploration sites for seafloor mineralization. The exploration protocols developed during these surveys include bathymetric mapping of mostly unknown volcanic edifices, followed by detailed water column profiling and sampling to detect and characterize volcanic fluid emission signatures. These procedures are being refined as the survey progresses, both for efficiency and as direct seafloor observations become available for predictive application of water column plume information to guide seafloor mineral exploration.

Jan 1, 2002