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By Holmes R. J, Miles J. G

An on-stream shale detector has been developed that is suitable for use on conveyor belts carrying iron ore of up to 200 mm particle size. The shale is distinguished from high-grade iron ore by means of the substantially greater total natural gamma-ray activity (400-3000 keV) of the shale, which is due to the presence of uranium (214Bi), thorium (208TI) and potassium (40K). Other gangue materials, sueh as highly siliceous cherts and jaspilites, escape detection because of their low activity. A dynamic trial of the shale detector at Mt Whaleback, using a large-volume (100 × 100 400 mm long) "Polyscin" Nal(TI) gamma-ray detector, demonstrated that as little as 20 tonne of ore on a conveyor belt (equivalent to partial truckloads of ore) can readily be monitored for shale content.

Jan 1, 1981

By A Raza, D P. Kohn, D A. Foster, A J. W Gleadow

A large and increasing data base of apatite fission track results from sedimentary and granitic rocks exposed within the south-eastern highlands and along the continental margin ofAustralia provides constraints for the tectonic development of the south-eastern passive margin. The fission track results suggest that many regions of the south-eastern margin of Australia experienced distinct episodes of relatively rapid cooling during the middle Cretaceous to early Tertiary that can be attributed to the effects of rifting. One cooling episode is middle Cretaceous in age and related to denudation of the south eastern highlands from Tasmania to northern New South Wales between ~90 - 100 Ma. Rocks exposed along the present coast line record a later episode of rapid cooling, which is diachronous and decreases in age northward from ~80 to 90 Ma in northern Tasmania to southern New South Wales, ~60 - 80 Ma in central and northern New South Wales, and to ~50 - 60 Ma in southern Queensland. The results are consistent with models suggesting that underplating occurred inward of the rift along the eastern margin of Australia as a result of the onset of continental extension in the Tasman Sea at ~96 Ma. This resulted in a significant change in base level and km-scale denudation of much of the southeastern highlands. Subsequently, as breakup commenced during the Late Cretaceous at ~80 Ma and continued into the Paleocene at ~60 Ma, the second stage of cooling was imprinted on the rocks along the margin. This cooling is probably due to the relaxation of elevated geothermal gradients associated with rifting as well as some denudation. Because rifting was oblique to the present-day coast, different regions record different ages of cooling associated with the rift. The southern regions of New South Wales and Victoria yield ages associated with earlier rifting while regions of northern New South Wales and southern Queensland give ages associated with later rifting.

Jan 1, 1995

Low displacement fault zones often comprise a mesh of interlinked faults, extensional-shear and purely extensional vein fractures. Hydrothermal mineralisation localised around such structures testifies to their importance as conduits for fluid flow. Mesh structures are most commonly developed in situations approximating bulk pure shear but predominantly simple shear meshes also occur. They appear to develop through the infiltration of pressurised fluids into a heterogeneous rock mass with varying material properties. In some circumstances, mesh formation appears to be a precursor to the development of major through going faults. Mesh formation generally involves hydrofracturing (Pf > s3, at least locally) and the condition Pf ~ s3 to be maintained for the mesh to remain a high permeability conduit, requiring fluid over pressuring at other than shallow depths in extensional-transtensional regimes. The volumetric character of earthquake swarm activity appears to result from the passage of hydrothermal fluids through mesh structures, representing a form of distributed fault-valve action along suprahydrostatic hydraulic gradients arising from magmatic intrusion, compaction overpressuring, metamorphic dewatering, etc. Fluid redistribution in the crust is influenced by maximum hydraulic gradient (not necessarily vertical), by existing permeability anisotropy arising from bedding and other forms of crustal layering, and by structural permeability developed under the prevailing stress field. Strong directional permeability develops in the s2 direction, parallel to fault-fracture intersections within the mesh and orthogonal to fault slip vectors. In particular tectonic settings, stress-controlled permeability allows strongly focused flow through fault-fracture meshes with high potential for mineralisation. Favoured localities for mesh development include short-lived link structures along large-displacement fault zones such as dilational jogs, lateral ramps, and transfer faults.

Jan 1, 1995

In preparing a paper such as this it was thought that the Newstan Colliery Company Ltd., being comparatively new, would need some introduction to mining people in general.The Newstan Company was formed by the Joint Coal Board in December, 1948 during a period of acute coal shortages. The Company took over the holdings of what were known as the Olstan and Northumberland Collieries, situated at Fassifern, alongside Lake Macquarie and adjacent to the Great Northern Railway, within easy rail access of Sydney and Newcastle, as shown on the locality plan (Fig. 1).The Company was developed in order to produce steaming coal for the power house trade and has continued its activities in the steaming coal trade since its inception. The Olstan and Northumberland collieries were together producing some 300 tons per day when the Company was formed, and it was from this foundation that the colliery was built. The planned development of the Company has been along the lines of producing coal by modern, highly mechanised methods, together with the preparation of theproduct for the consumer, to the highest degree possible consistent with up to date methods.In the comparatively short time of 5t years the mine has developed from a small hand-won coal unit to a high capacity modern mine, one of Australia's largest producers, with an output capacity as high as 3,000 tons per shift.

Jan 1, 1954

By G J. Lyman, S A. Tittlemier

International regulations exist to manage the concentrations of mycotoxins such as Ochratoxin A (OTA) and deoxynivalenol (DON) in grains and prevent health risks from excessive exposure to OTA and DON. Since the permitted levels of these mycotoxins are very low (existing maximum levels are in the range of 5 ppb for OTA and 1–2 ppm for DON), sampling for these mycotoxins is potentially challenging. Given that the distribution of infected kernels in a consignment of wheat can be highly heterogeneous, detection by current sampling methods is subject to a high variance. Furthermore, the concentrations of mycotoxins in individual kernels vary over orders of magnitude, intensifying the heterogeneity of the bulk grain.In these circumstances, there is much interest in developing sampling plans that inform regulatory agencies, and mitigate the risk of misclassifying grain shipments as compliant or non-compliant within the global grain trade, when correctly implemented.Experimental data from laboratory and field studies describing individual wheat kernel concentrations of OTA and DON were combined with experimental data describing the variance due to the analytical methods used for OTA and DON to calculate the sampling distribution for wheat having various levels of contamination. This work has focused on quantifying the heterogeneity of samples at the point of submission for analysis and within subsequent sample preparation to arrive at total sampling distributions that include uncertainties due to the intrinsic heterogeneity and the analytical uncertainties. The sampling uncertainty that relates to the difference between the primary sample analysis and the true lot analysis is not included as it has been dealt with elsewhere.CITATION:Lyman, G J and Tittlemier, S A, 2017. The sampling characteristics of grains contaminated by mycotoxins, in Proceedings Eighth World Conference on Sampling and Blending , pp 281–294 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2017

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

By C N. Whata

While there is no specific obligation on the part of any applicant to consult directly with tangata whenua (people of the land), recent cases highlight the need to engage in active consultation in order to avoid serious objections and delay, particularly where a proposal may affect the matters referred to in section 6(e) (Waahi tapu/sacred places) and 7(a) (KaitiakitangaiGuardianship) of the RMA.   The Environment Court has shown some sympathy for tangata whenua where waahi tapu and other significant matters of cultural concern are at risk because of a proposed development. There are several practical steps that can be taken to minimise the potential for serious objection including: ò knowing who to contact and how to contact them; ò demonstrating empathy for the concerns of tangata whenua; ò engaging in proactive consultation, for example meeting at a time and a place that is suitable to tangata whenua, and a preparedness to meet the costs of tangata whenua etc; ò demonstrate an awareness of tangata whenua issues; being aware of the types of mechanisms that are available to remedy, avoid etc adverse effects on matters of concern to tangata whenua.

Jan 1, 1997

By M Quinteiro, Å Sundqvist

What is special about being a female mine manager? We do not believe that the challenge is greater for women in managing a mine compared to managerial positions in other male-dominated businesses. The challenge lies in the fact that it is a male-dominated business. Being a leader belonging to a minority creates a situation where competence not only lies in having technical knowledge or general leadership characteristics, but also in acquiring an understanding of the male norm and being able to behave and communicate effectively in the organisation.In order to move towards a better gender balance at senior levels it is important to set measurable objectives on desirable proportions between women and men at management levels within the company. Focus and action are required to achieve this goal. At LKAB, the current target is to reach 25 per cent women in the total workforce by 2020. To date, LKAB has reached 19.4 per cent women in the total workforce, and the number of women in management positions is 19.9 per cent.It is of vital importance to create a non-discriminating working environment to achieve equal opportunities at the workplace, to be able to use the whole workforce as a resource for recruitment of professionals and managers, thereby improving decision-making, productivity, efficiency and profitability.Women as mine managers is not a utopia, but rather an effect of long-term investments in actions that result in equal opportunities for all employees.CITATION:Quinteiro, M and Sundqvist, Å, 2016. Women as mine managers – a utopia?, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016) , pp 43–48 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

In blasting large tonnages of ore or material, the economy of the operation 'depends mainly on the mine manager's judgment in placing the holes to the best possible advantage and in determining the most effective size of hole to suit the conditions and requirements.The placing of holes is often looked upon as a problem involving so many uncertain factors that the application of simple mathematics is impossible. The uncertain factors arise when dealing with strata of different character, in hardness toughness and resistance to shearing.A study of the practice at many mines where all types of strata from hard ore to relatively soft overburden, and even coal, is being mined, suggests that the problem is not as complex as generally believed. There is, without doubt, some uniformity in the amount of burden given to holes of equivalent dimensions, regardless of the material being mined. The reason is simple. With too great a burden hard rock will not break out and soft rock will "bull". The nature of the strata is taken care of by the strength, quantity and distribution of the explosive charge and, to some extent, the spacing of the holes.It is because burdens are uniform in all classes of strata met with in mining, that a formula can be used to design blast hole layouts.The formula introduced in this paper is empirical as it is based on prevailing practice. It has been tested and proved remarkably accurate against every example available to the writer. Many thousands of blast holes, at many different mines, are represented by the examples given in the attached tables; to give further examples would only mean, unnecessary repetition. At the Mount Morgan Mine...

Jan 1, 1952

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

Concentration of Phosphate Ore by Flotation With/Without Desliming

Sep 13, 2010

The disasters between 1920 and 1979 in coal mines in Queensland and New South Wales due to underground fire, gas or coal dust explosion or to gas or coal outbursts, have been assessed. The evidence relating to disasters caused by gas explosion points strongly to divergence from safe mining practice as the main cause. There is a need for greater training and education of personnel, closer analysis of gas reports, better monitoring and testing procedures, improved ventilation standards and a policy where safe working practice is actively encouraged. Conditions in the New South Wales occurrences of gas explosion were similar to those at Collinsville, Queensland in that dykes, igneous sills, burnt out coal and faulting were common to all. Information on outbursts indicates that contributing factors were intrusions, depth of cover, fault zones and other geological disturbances, methods of work, pressure and type of gas.

Jan 1, 1982

Physical/Chemical Treatment of Mercury-Contaminated Wastes from Former Chlorine-Alkali Electrolysis Plants - Application of Flotation Technologies in Soil Washing Plants

Sep 13, 2010

In an earlier paper (Stanton, 1953) a brief account was given of the geological environment and structure of the Lloyd Copper Mine orebody, Burraga, N.S.W. The present paper is concerned with the chemical and mineralogical features of the ore from this mine.Investigation has been made difficult because of inaccessibility of the workings, which have been fallen in for many years. The exact positions within the orebody of the specimens described in this paper are known in only a few cases. The specimens examined are from the collections of the Mining and Australian Museums, Sydney, and from material collected by the writer from the upper parts of the mine and from various dumps about the old workings.However, no significant variations in the nature (as distinct from grade) of the ore have been mentioned in the old reports, or by Carne (1908) or Kenny (1928), so it is likely that the specimens examined are reasonably representative of the orebody as a whole.CHEMICAL CONSTITUTIONThe ore is of simple and apparently very uniform composition.It is essentially a copper ore, with minor amounts of zinc and very minor amounts of lead. Plotting of copper against zinc shows a more or less sympathetic relationship between these at least as far as 20 per cent. copper - the highest grade assayed during the present investigation. The trend of the plots indicates a Cu/Zn ratio of about 15/1 to this point. Lead is very low and extremely sporadic, showing no clear relationships with the other metals.MINERAL COMPOSITIONThe principal non-opaque minerals are quartz and sericite, and these are accompanied by smaller quantities of muscovite, calcite and biotite. Quartz is the most abundant mineral, occurring both as a C'onstituent of the country rock a quartz-sericite schist-and as veins. All quartz aggre...

Jan 1, 1955

By Met B. E

During the operation of the Parkes process of desilverising, and in the earlier days of the continuous process, gold and silver were removed separately from softened lead bullion. Gold was removed in the Parkes process by a selective zincing, and -in the continuous process by treatment with zinc in a special de-golding kettle, in each case a crust being obtained carrying the gold and a small portion of the silver. Actually the process could have been more correctly termed a de-copperising process, on accountof the relatively large amount of this metal present, and its affinity for zinc, which caused it to enter the crusts produced.The crust was treated in reverberatory furnaces, where the bulk of the copper and zinc was removed in by-products, and the resulting "gold bullion" cupelled to give adore bullion containing approximately 2,000 ounces gold per ton.For the purpose of parting this dore, a small Balbach-Thum plant of 11 cells was used, and once each six months a short campaign was conducted on the accumulated metal.With the development of the process of de-copperising smelter bullion by means of sulphur, when a bullion averaging about .004% copper was constantly available for refining, the need for a separate de-golding process disappeared.The de-golding kettle of the Continuous Process...

Jan 1, 1937

This paper examines the reform of mining legislation over recent years, the establishment of new Crown land management agencies, and the role of the Crown and environmental groups in nature conservation inNew Zealand. It describes the relationship of the minerals industry to the Department of Conservation and environmental groups over recent years, and the prospects for mineral development on the Conservation Estate in future.

Jan 1, 1995

This technical note describes a problem with WANG82, a ventilation network analysis programme. The problem was highlighted by Renison Ltd when using the programme on large, complex networks. Under certain circumstances the programme produced incorrect results or failed to converge to a solution.

Jan 1, 1986

By D Craw, K A. Hunter

Deposits of the metalloids arsenic and antimony occur in quartz veins of mesothermal hydrothermalsystems in the South Island as arsenopyrite (AsFeS) and stibnite (Sb2S3). Arsenopyrite and stibnite occur in natural exposures in gold-mining areas, and additional arsenopyrite and stibnite have been exposed to the atmosphere by mining activity. At present the drinking water limits for dissolved As and Sb are 10 ppb and 3 ppb respectively. Sampling and analysis techniques are critical to determination of metalloid concentrations at these low levels. Endeavour Inlet in the Marlborough Sounds is an historic mining area (late 19th Century) with elevated As and Sb in waters emanating from mineralised rocks. Waters running out of abandoned adits have concentrations of As and/or Sb up to ppm levels. Natural waters have high Sb and low As, and the As levels increase markedly where anthropogenic activity has exposed rock. Changes in Sb/As ratio could potentially be used to quantify the anthropogenic component of metalloid mobility on mine sites on the 100-year time scale.

Jan 1, 2002

The paper outlines the development of a solvent extraction process for the recovery of scandium, yttrium, thorium, and heavy lanthanides from waste sulphate liquor at the Port Pirie uranium treatment plant. A summary is given of known solvents for these elements, including the recently developed alkyl-phosphoric acid esters which are applicable to sulphate solutions.A kerosene solution of di- (2'-ethylhexyl) phosphoric acid (EHPA) has been suggested by some workers as a suitable solvent for fractionation of the lanthanides. Experimental work with this solvent showed that it could be used for initial recovery of the above elements from low concentrations in the complex sulphate liquor. In particular, scandium could be recovered as a high grade product by extraction with 0·lM EHPA, followed by a purification strip with 9N sulphuric acid, and final stripping of scandium with sodium hydroxide solution.To enable alkaline stripping to be used successfully, the kerosene solution of the reagent was modified by the addition of a small proportion of nonanol. Experimental work included laboratory scale batch tests and small pilot scale continuous tests.A proposed extension of the process for the separate recovery of individual heavy lanthanides, yttrium, and thorium is described.INTRODUCTIONAt the Port Pirie uranium treatment plant of the South Australian Government, large volumes of "barren liquor", free from 'uranium, are at present run to waste. This "barren liquor" results from sulphuric acid leaching of Radium,Hill uranium concentrate, followed by separation of solid residues and removal of uranium from the clear solution by ion exchange. The mineral davidite, from which the uranium is derived, contains other potentially valuable components, notably vanadium, chromium, thorium, yttrium, scandium, and the lanthanides. These constituents are...

Jan 1, 1961

In formulating its strategic plan in 1998 the New Zealand Minerals Industry identified two related critical issues facing it. These are, broadly speaking, the issues of access to minerals; and the perception the public has towards the industry and its behaviour towards the environment. This presentation will report on the Industry's response to the public perception issue. The Industry has, through the NZMIA Council, and its Communication and Website Committees, developed and implemented strategies covering: communication through the print media, and through its website www.minerals.co.nz, a long-term educational outreach programme with schools, focussing on the significance of minerals, their contribution to community wellbeing and the negligible long-term environmental effects of the Industry's activities.

Jan 1, 2000