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Collecting the clay fraction of active stream sediment from a flowing stream for geochemical analysis i a difficult process. One either takes a sample of dry fine-grained sediment from the stream bank (dry weather and dry sample are uncommon in parts of New Zealand and Tasmania), or dredges up a sample of sand and mud out of the stream.The latter method produces a soggy ample bag full of mud and sand, with varying amounts of gravel, depending on the size of the stream. The water can be filtered from such a sample by means of a Buchner filter funnel, but is difficult to obtain a vacuum in the bush. This problem can be solved by using a small hand- queeze bellows such as used in priming petrol pumps on outboard petrol motors. The common laboratory hand bellows is not powerful enough.A 70 mm diameter two-piece polythene Buchner filter funnel (Fig. 1) can be used. A length of rubber tubing is fitted around the inlet valve of the hand bellows and this valve is then jammed into the pipe at the bottom of the filter funnel (the polythene pipe may be trimmed with a knife to fit over the inlet valve of the bellows). The vacuum is generated and maintained by squeezing the hand bellows.The technique of collecting a sample of the clay fraction is to dredge a sample of the fine-grained active stream sediment out of the stream with a container, such as a plastic mug. The sample is agitated to get the clay fraction into suspension and the muddy suspension is then decanted into the Buchner funnel. The desired clay fraction is obtained as a thin film on the filter paper.If the "fines" are also required, a filter of nylon bolting cloth (stretched across the mouth of a short length of 80 mm diameter polythene pipe and attached by rubber bands or a concentric polythene pipe) can be placed over the mouth of the Buchner funnel and the whole sample of stream sediment...

Jan 1, 1969

By J Fut=

The rotary drilling of rocks is widespread technology in mining and in tunnelling. The paper describes the results of research by aim to find relationships between optimal drilling and sound signal of drilling machine. The optimisation criterion has been formulated as the minimisation of specific energy with maximal effective speed of drilling in process of the rock disintegration. The research in this field has been made on experimental drilling stand. Our monitoring system has measured following variables: the pressing force of core drill, the revolutions of drilling head, the length of drilling, the time, the power, and the acoustic signals. For measurement of acoustic signals have been used very sensitively sound meter MEDIATOR 2238. From this measurements have been processed acoustic spectrums. Then we are found relationships between optimal control of drilling and composition of acoustic spectrum. On base of experimental results, we can formulate the optimal control following: æTo achieve the minimum difference between the equivalent sound level at the load and idle modes only at the representative frequency (f = 1000 Hz)Æ. The representative frequency dependences on type of the rock New method based on these relationships enables the optimal control of drilling machine by using measured acoustic signals only.

Jan 1, 2003

Sapporo-Iwanai district is located at the intersection of the northeast Japan arc and Kuril arc, associated with the subduction zone. This area is characterized by Miocene submarine volcanism followed by Plio-Pleistocene subaerial volcanism.   Koryu, a small epithermal Au-Ag deposit, occurred in Pleistocene (1.4 - 0.85 Ma) within Miocene sedimentary rocks near a subaerial andesitic volcano, while Toyoha, a large epithermal Pb-Zn-Ag (-Au) deposit, also occurred near a subaerial andesitic volcano. Although most of the base metal deposits formed in middle-late Miocene, Toyoha formed in Plio-Pleistocene (2.93 - 1.60 Ma) within Miocene volcanic and sedimentary rocks. This epithermal mineralization was partly overprinted by xenothermal Cu-Sn-In(-Au) mineralization (2.68 - 0.49 Ma).   Hydrothermal alteration differs vastly between Koryu and Toyoha: host rocks at Koryu were not intensively altered, although wall rocks adjacent to veins were silicified, while those at Toyoha show intensive and extensive neutral-pH alterations. Geological and chronological studies show that middle~late Miocene (12.5 - 8.4 Ma) alteration was pervasive and overprinted by Plio-Pleistocene (2.93 - 0.49 Ma) alteration. The base metal veins in the middle-late Miocene were not well developed, but were large in number with great depth.   These studies show that the hydrothermal activity at Koryu is rather small and short-lived, while that at Toyoha is large, long-lived and characterized by overprinting of different hydrothermal systems. The subaerial magmatic activities yielded not only the andesite lavas, but also generated hydrothermal solutions for the formation of both Koryu and Toyoha. The metals were possibly derived from such magma. At Toyoha, the hydrothermal solutions could also remobilize metals from old ores.   The size, life span of magmatic-hydrothermal system, and overprinting on the old mineralizing systems could constrain the type of metal deposits (precious and polymetallic deposits) nearby subaerial andesitic volcanoes in Plio-Pleistocene.

Jan 1, 2005

An important consideration in any mining operation is waste disposal management. Tailings management at Macraes gold mine allows for the disposal of tailings into fully engineered embankment dams and overburden material to be incorporated as construction material into those embankment dams. This paper outlines the current tailings management practices.

Jan 1, 1992

With some notable exceptions, marine placers located just below, or just above, present sea level, are responsible for much of today's production of detrital ilmenite, rutile, zircon, and other minerals of value. The purpose of this paper is to discuss the paleogeographic and paleo-oceanographic factors which may have determined the location of presently submerged marine placers. These factors include changes in sea level, burial by recent marine sediments, stream capture and other changes in drainage patterns, and recent changes in climate. Selected geologic situations in the Yellow Sea off the coast of Korea, in the Atlantic Ocean off the coast of Portugal, in the Bering Sea off the coast of Alaska, and in the Arabian Sea off the coast of India, will be used to illustrate the author's point of view.

Jan 1, 1971

Drilling in the south of the Rapahoe Sector at Greymouth Coalfield has demonstrated the existence of thick coal seams in the upper Rewanui Member. Seam correlation is handicapped by complex lithostratigraphy and laterally variable geophysical log profiles. An integrated investigation of coal measure stratigraphy, coal petrology, and proximate analyses, suggests a feasible model whereby most of the major seam intersections belong to a single horizon. Coal properties vary laterally in response to original swamp conditions, which are believed to have ranged from well-drained to ponded. A new model of peat accumulation is proposed for the northern Rapahoe Sector, whereby Upper Rewanui peat accumulation occurred on a flood plain between the levees of a major south southwest-flowing fluvial system in the east and the toe of a western alluvial fan.

Jan 1, 1985

The early history of the mine is traced from the beginning of shaft sinking in 1886 to the purchase by the Broken Hill Proprietary Co. Ltd. in 1949. A necessary preliminary to mechanisation of the Borehole Seam was development of the Young Wallsend seam, andthis development is described. Surface reorganisation and coal handling arrangements are dealt with in detail. Then follows a description of the Borehole Seam mechanisation, the provision of power supply for this purpose, arid pumping arrangements in themine.INTRODUCTIONStockton Borehole Colliery is in the Parish of Teralba, between the townships of Teralba and Boolaroo, and about 12 miles from Newcastle. The colliery holding, a freehofd area of 2,560 acres, was apparently an original land grant when acquired by Teralba Co-operative Coal Company who decided to mine for coal and named the mine "Teralba Colliery." Shaft sinking was commenced in 1886 but was delayed by financial and water troubles to such an extent that it was not until 1901 that the Borehole Seam was reached.Coal was won until 1904 using a single 16 ft. diameter shaft, ventilation being achieved by means of a wooden boxing down one side of the shaft. This collapsed, and operations ceased until the mine was taken over in 1906 by a company known as "Borehole Colliery Limited," the principal stockholder being the Stockton Coal Company. It renamed the mine "Borehole Colliery." This new company immediately commenced sinking a 13 ft. diameter air shaft. In 1908 the Stocktol1 Colliery at Stockton was abandoned, and during the following year much of its equipment was transferred to Borehole Colliery. The name was again changed becoming "Stockton Borehole Colliery." From this period on, coal was produced from the Borehole Seam by...

Jan 1, 1957

The Telfer main dome open pit is operated by Newcrest Mining Limited at a current production rate of 50 Mt/a from a pit dimension compromising 2 km strike length, 1 km width and 250 m depth. As part of the refeasibility of the Telfer operation undertaken early this decade, Newcrest identified that an underground sublevel cave (SLC) operation along with an increased scale of open pit would support a new plant targeting the processing of gold and copper ore at 17 Mt/a rates. The SLC was initiated in late 2006 and broke into the open pit in late 2009. This situation is unique across the mining industry where a cave breakthrough was planned and occurred within an active large open pit operation. The SLC broke though into the west side of the Main Dome open pit into a specially prepared bench that was left at the 5384 RL of cut-back stage 3. A main haulage ramp is within 100 m from the edge of the cave breakthrough zone and this ramp passes down to the active levels which are progressing toward the 5200 RL. This paper presents insight into the mine planning and risk management associated with continued operation of the open pit operation while an active SLC breaks through. The cave breakthrough presents unique areas for risk management as there is potential for rapid propagation and subsidence. To support the undertaking, mine design and major hazard management planning has been carried out. Focus areas include; dual ramp system design, preloading the breakthrough area, monitoring of cave propagation and air gap using a seismic system and deep hole extensometers, wall stability and subsidence monitoring using radar and prism systems, and key trigger and response planning.

May 1, 2010

During an eight month period, January to August 1978, nine bore holes were drilled in the Mikonui River gravels. On account of two rebores required from near bottom, the number of bores is in effect 11. Just on 1300 feet were drilled with an average depth of 120 feet. Depth varied from 102 feet to 133 feet. Penetration on average per hole value, varied from 7.4 to 16.4 feet per day. Gold values were even more erratic. Drill rig used was the Keystone churn drill manufactured locally by the Dispatch Foundary. It is skid mounted and requires a crew of two persons.

Jan 1, 1979

By A H. Clemens, T A. Moore

This paper discusses a number of technical issues related to marketing coal. It outlines how the results of research undertaken in New Zealand and overseas can help producers address a range of technical factors that impact on production costs and marketability. The paper also discusses trends in coal utilisation for power generation and how new technologies may require coal with different characteristics. Research and development into options for CO2 sequestration are discussed including carbon storage in forests, and removal of CO2 from flue or fuel gas in power stations, and its disposal.

Jan 1, 1997

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 T Howard, J E. Everett

BHP Billiton Iron Ore has replaced the conventional product quality control batch system at Yandi with the Continuous Stockpile Management System (CSMS) centred on a fully integrated æcontinuousÆ stockpile flow from mine planning through to port reclaiming. With increasing tonnage rates, tight operational coupling associated with the original batch system caused production interference which achieved final product quality but in an increasingly inefficient manner. This innovative approach places a continuous emphasis on product grade control and takes full advantage of the most appropriate blending opportunities of the mine to port planning and production system in order to reduce the natural variability of the ore to an acceptable level. To implement continuous control, product variability throughout the process is classified as long-term and short-term. Long-term variability is best controlled through the monthly mine planning process which determines monthly grade targets while taking into account optimum mine development. In the past, attempts to control long-term variability were made at the port through selective stockpiling and reclaiming which reduced operational efficiency. Short-term variability is best controlled around the monthly mine grade target by daily mine production scheduling, train sequencing, stacking into port stockpiles of appropriate size and systematical stockpile reclaiming. The implementation of the new system has maintained customer accepted shipping grades and has provided significant improvements in resource utilisation, operational efficiencies and costs.

Jan 1, 2002

A description is given of preliminary work done to identify the problems inherent in electrochemical oxidation of metal sulphides, and particularly in the use of powder compacts as anodes in electrolysis. Lead flotation concentrate pressed into a compact can serve as an anode for direct electrowinning of lead according to the reaction PbS -7 Pb2+ +So +2e. No pYrometallurgical step is required, and sulphur is recovered in elemental form.In the experimental work, electrical conductivity of the compacts was achieved by addition of 5·5 per cent of graphite. After compaction at 10-20 tons/sq. in. the anodes were strong and remained intact throughout the electro-oxidation period. Perchlorate electrolyte was used, but fluosilicate electrolyte is also applicable. A sheet of pure lead formed the starting cathode.As anode potential increased above 1·0 V (v. SHE) PbS04 was formed in increasing amount. At 0·90 V, Pb2+ extraction efficiency was 85 per cent. Anode potential was kept low by electrolysing at 60°C and 15 mA/sq. cm., and by improving the porosity of the compact. Other metal sulphides (Zn, Fe, Cu) in the flotation concentrate also oxidize and release metal ions to the electrolyte, which would need to be purified prior to deposition of lead.Power requirement in a laboratory cell was about 0·24 kWh per lb of lead extracted.

Jan 1, 1972

A single compartment 100 A electrolytic cell charged with AICla-KCl-NaCl at 750°C was studied during an experimental campaign of 4 months. About 10 1b of aluminium were produced in continuous runs which lasted up to 1 week. The highest cathode current efficiency determined was 80 per cent. Anode current efficiency. cathode potential, analyses of melt, sublimate, and product, and reactivity of cell materials were also recorded and interpreted in terms of the role of lower valent aluminium species in the electrolysis mechanism.

Jan 1, 1971

The Misima open pit gold mine is a 20Mt per annum operation. Blasthole drilling is used to sample all material at a uniform 5m square pattern, and representative sub- sampling of the blast holes enables assay samples to be collected over the full 10m bench height. Samples are assayed for gold, silver and copper at the Company's laboratory at the mine site and the assays are provided to geologists as a written assay report and on floppy disc. Surveyed blasthole locations and assay results are transferred via personal computers (PCs) to a SUN mini-computer where results are stored by bench, blasthole assays are kriged, and plot files are created. A geologist selects grade boundaries from the kriged data, adjusting the boundaries towards the raw blasthole data where hard boundaries are recognised. Surveyors peg the resultant boundaries in the pit using a system of colour-coded pegs to display the different material types. A daily plan also shows boundaries and face positions.

Jan 1, 1991

The following paper outlines the types of employment immediately available to graduates following their university degree, a discussion on mine manager requirements, mentions career advancement and time frames to achieve this as well as providing some key information regarding student vacation work. The author hopes to educate present graduates, as well as inform students of characteristics to develop the most opportunities in life.

Jan 1, 2006

By Spooner H. W

The paper describes the search for mineral deposits in an area of 4,500 sq. miles of south-west Tasmania. The area is one of difficult access and the problem of speedy movement and maintenance of field parties was solved by the use of helicopters. The programme has followed a systematic pattern of the aerial photography of the exploration area with the preparation of photQmosaics and topographical base sheets from these mosaics. Geological maps were initially prepared by photogeological interpretation and making use where possible of pre-existing information. The maps produced were later checked by ground traverses. Geophysical maps were obtained by the use of airborne magnetic, electromagnetic and radiometric methods. Geophysical and geological anomalies were checked on the ground by a campaign using ground geophysical equipment in the former case and geological and geochemical work in both instances. Audio Frequency Magnetic and Induced Polarization techniques were used in an area which was covered by several hundred feet of Tertiary sediments.The campaign has reached the stage of the drilling of specific targets.INTRODUCTIONThis paper describes the activities of Lyell-E.Z. Explorations (L.E.E.), an organization which was formed in 1956 by the Mt. Lyell Mining and Railway Co. Ltd. and the Electrolytic Zinc Co. of Australasia Ltd. to explore for mineral deposits in an area of approximately 4,500 sq. miles in southwest and southern Tasmania. To provide the necessary personnel and equipment for this project the exploration resources of both Companies were pooled and augmented and a headquarters was established in Queenstown. The work was directed by a Committee of four made up of officials from both Companies; a review of this structure has recently been presented by Hall (1959).

Jan 1, 1960

By A J. H Newell

The background and the basis for conducting a Technical Due Diligence are discussed as well as the source information, typical studies and potential limitations. Typical short comings including ‘show-stoppers’ are presented for the metallurgical area, with examples. Issues found in other areas such as geology, mining, infrastructure and financial evaluations are briefly reviewed, highlighting the input and interaction required by metallurgists with these disciplines. A checklist is provided as a guide to maximise the success of a Due Diligence as well as a check on the quality of a Feasibility Study.CITATION:Newell, A J H, 2015. Fatal flaws in technical due diligences, in Proceedings MetPlant 2015, pp 61–77 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 7, 2015

By E Breese

The Grey River dredge is the first large scale alluvial operation to be permitted under the Mining Act 1971 and the Water and Soil Conservation Act 1967. The experience of Grey River Gold MiningLimited in pursuing these statutory approvals has identified weaknesses and strengths in the present system and problems which need to be resolved. The Company has learnt lessons, which if heeded, will assist future large scale alluvial mining projects.

Jan 1, 1989

Mineral Processing Engineering Education in China - Bringing up the Engineering Diathesis and Design Competence of the College Students

Sep 13, 2010