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Aspects of sampling are becoming more complex, involving a correct statistical approach to collection as well as geological and possibly pedological control. Advanced chemical techniques and techniques of rapid analysis need to be understood. Results may require statistical analysis. The elementary aspects of sampling still need constant attention by those controlling a programme of sampling. No one person will have sufficient knowledge of statistics, geology, pedology and chemistry to be fully conversant with all the aspects of sampling but, by developing a correct approach, problems can be identified and solved.

Jan 1, 1976

The mining activities on the North Mine leases have, over the years, followed the orebody from the shallower depths at the southern end of the lease as it continued northwards at progressively increasing depths.Commencing from the south end, in the early days small shafts were used to obtain access to the orebody at the moderate depths involved.

Jan 1, 1957

By Daoust G, Dubois JF

The optimal sequence of decisions on rates of production and cutoff grades is obtained by a dynamic programming model. The main parameters are : 1. the size of the deposit, average grades and grade distributions, 2. the operating costs of mining and concentration, 3. the investments in mine and mill, 4. the smelter charge, 5. the price(s) of the metal, 6. the recovery and the grade of the concentrate, 7. the rate of interest, 8. the taxation formulae, 9. the upper limit to rate and the rate interval and 10. the upper and lower limits to cutoff and the cutoff interval. An amount of ore can be mined at various rates while applying various cutoff grades. It is assumed that a decision to mine at a certain rate during a period conducts to a certain state regardless of the cutoff grade. This assumption which is valid for several

Jan 1, 1977

By J J. Jiang, B G. Bow

Atlas Iron Limited’s (Atlas) Abydos Mine has developed its Scarborough open pit proximal to a rock shelter that has been assessed as a significant Aboriginal heritage site by the Traditional Owners of the land. The rock shelter, named Yurlu Kankala, is located to the north-west of the pit with a stand-off distance of 35 m. Within Atlas’ Native Title Agreement with the Traditional Owners, and approvals from the Western Australian Department of Aboriginal Affairs, commitments have been made to conduct mining in a way that avoids or at least minimises disturbance and damage to the rock shelter. This complies with the Aboriginal Heritage Act 1972 (WA) and respects the heritage and culture of the Traditional Owners.CITATION:Bow, B G and Jiang, J J, 2018. Iron ore mining in proximity to a significant Aboriginal heritage rock shelter, Pilbara Region, Western Australia, in Proceedings Life-of-Mine 2018, pp 2–5 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 25, 2018

By Heesteman LJL, Turvey DJ

The Mangani mine in West Sumatra is historically one of the most important precious metal mines in Indonesia, although the past production by World standards is small, totall- ing 5.66 tonnes gold and 242 tonnes silver. The geology is dominated by a distinctive NW-SE graben structure formed by dextral splay faults from the Sumatran Fault System. Quartz- rhodochrosite-rhodonite-Ag-Au veins are hosted by Tertiary pyroxene andesite volcanics and quartz-phyllite conglomerates, on N-S tensional fractures which intersect the Mangani graben. Intrusive rocks include andesitic dykes, pyroxene microdiorite, and hornblende granodiorite. Quartz-epidote-pyrrhotite alteration is related to concealed intrusions. Precious metal vein mineralization is characterized by: high Ag/Au ratio (>25); complex sulphide mineralogy of Fe, Mn, Ag, Cu, Pb, Zn, As, Se and the occurrence of Sn as stannite; low total sulphide content (

Jan 1, 1987

By Klenowski G, Gilmour G. A

The Metropolitan Water Supply, Sewerage and Drainage Board, Perth, has recently con- structed two major sewerage tunnels in the metropolitan area and a further one is under construction. These tunnels were constructed in sand, sandstone and limestone. The Tamala Limestone is a Pleistocene calcareous dune sand which now varies in com position from loose sand to cemented rock. Investigation techniques included surface mapping, auger and diamond core drilling, seismic refraction geophysics and mechanical testing. The variable nature of the ground caused difficulties in all aspects of the investigation, particularly in core recovery and seismic work. The Beenyup Tunnel, 2.25m in diameter and 3440m long was excavated with a Dosco TBM 1800 machine and shield with precast concrete Charcon Universal bolted segment lining. The Burns Beach Sewer Tunnel, 1.27m in diameter and 860m long was hand excavated with precast reinforced concrete lining pipes jacked continuously behind an excavation

Jan 1, 1981

Life inside the mining family was regulated by the mine. The whistle shrieked the change of shift to the Cornish, Welsh and German miners digging the alien soil for copper at Burra in the 1840s and the deep quartz gold mines at Bendigo in the 1880s.During the golden years of alluvial mining in the 1850s, and later out on the frontier fields of Kalgoorlie and Jarrahdale in Western Australia, the lure of the mine dominated family life. How could it do anything else? The canvas tent, bark hut or weatherboard cottage in which the mining family lived close by the mine facilitated prompt access. The working man of the family attended to the demands of the mine first, and those of his family afterward. Who then organized and nurtured the mining family? The role of the mining wife was multi-fold. She played the traditional roles of home-maker and comforter, raising her children, tending her house and vegetable garden and supporting those friends and acquaintances who had lost children to disease, or menfolk to the mine. Epidemics of measles, the whooping cough or influenza carried away children in infancy or at too young an age. The death of a husband through accident or disease (pthisis was a likely killer) forced upon the mining wife another role, that of provider. When Elizabeth Vigus' husband died in a Bendigo mine accident in March 1880 Elizabeth set up a grocery business to support her young children.' But in other cases the mining wife supplemented the family earnings by part time work, not in the mines for the Mines Act legislation of 1842 forbade the working of women underground, but in auxilfiary occupations which were in demand.2 Ann Mitchell, a herbalist ,found plenty of work in the goldfield towns of Daylesford and Maldon in the 1860s and 1870s.3 So too did Susan Rule and her daughter Catherine who conducted a sewing and millinery establishment in Beechworth in the 1870s.4 The making of the family's clothes was another task of the mining wife and mother.Until the wonderful invention of the sewing machine, this was a tedious and time-consuming task. James Slater Edmonson bought his wife a Wertheim for the sum of 12 pounds in June 1886, just before leaving her and his chil- dren in the Adelaide suburb of Goodwood whilst he went alone to the goldfields of the West. In October of that year he wrote to Louise telling her how he missed the childrens' wondering "whether Slater wore my old shirt now. I always think of him as he sat on my knee at breakfast in that old shirt; and how pleasant it would be if I could rock both of them and sing as I used to do".5

Jan 1, 1988

By T Ye Koltunova an, L A. Otrozhdyonnova

This paper presents the results of studies on the development of an efficient non-cyanide technology for processing massive, finely disseminated, copper-zinc ores of the Urals deposits. Copper is mainly represented by chalcopyrite and zinc û by sphalerite. The main ore mineral is pyrite, with its content in ores varying from 50 to 80 per cent. At the present time, separation of copper concentrate at the Urals concentrating plants is achieved in a lime medium by non-cyanide technology using sodium sulfide and zinc sulfite as depressors of zinc and iron sulfides and butyl xanthate as the collector. Copper content in copper concentrates amounts to 15 - 17 per cent; considerable losses of zinc are associated with copper concentrate and final tailings. Various collectors were tested during the studies: xanthates and aerofloats with different lengths of hydrocarbon radicals, thionocarbamates, Aerofine 3418A of Cytec Industries, reagent S-703G of Mineral Reagents Int, and modifiers û sulfur dioxide, sodium sulfide and zinc sulfite, with a pH of the medium varying from 5 to 12. Optimum results of copper concentrate separation were achieved in a weakly acidic medium using S-703G as the collector and sulfur dioxide and zinc sulfite as modifiers. The copper content in the copper concentrate was increased by 4.8 per cent. Total copper recovery into the copper concentrate and zinc recovery into the zinc concentrate exceeded five per cent.

Jan 1, 2005

The goal of the Bureau of Mines, U. S. De- partment of the Interior, diesel engine research program is to reduce exhaust emissions and mini- mize the risk of fires and explosions caused by the use of diesel-powered equipment in under- ground mines. Significant results of research conducted during the last 5 years are briefly described, with references to published reports on specific topics. Topics covered here include brief discussions of a newly completed diesel research laboratory, the effects of a fuel addi- tive on diesel exhaust particulate matter, the effect of diesel engine maintenance on emis- sions, a diesel particulate filter for equipment used in underground metal and nonmetal, and coal mines, and lastly, the prototype hydrogen- powered mine vehicle. These research accomplishments could favor- ably affect the mining industry by reducing the health and safety hazards associated with the use of diesel-powered equipment in underground Mines.

Jan 1, 1988

The Kyaukpahto gold deposit is located at latitude 23¦ 47Æ 55" N and longitude 95¦ 56Æ 35" E in the Kawlin-Wuntho district, Sagaing Division, Myanmar. Gold mineralisation is hosted in sandstone of the Male Formation (Eocene) and occurs as stockworks and disseminations. The high-grade gold mineralisation is locally concentrated in a breccia zone. The gold deposit is closely associated with a NNE-SSW trending fracture system that forms tensional open fractures. These tensional zones are thought to be directly related to the Sagiang transfer fault system that experienced several hundred kilometres of northward dextral movement during the post-Upper Miocene. Major sulfide minerals are pyrite and arsenopyrite with minor galena, chalcopyrite and sphalerite. Gold mineralisation is associated with intense silicification, sericitisation and argillic alteration. Primary Type I fluid inclusions in the quartz from the mineralised zone are 5 to 15 ¦m across and yield homogenisation temperatures of 239¦ - 310¦C and salinities of 1.2 - 10.9 wt per cent NaCl equivalent. Laser Raman spectroscopic analysis indicates the presence of CO2 and CH4 in Type II fluid inclusions. Sulfur isotope analysis of disseminated pyrite in the ore zone by the laser ablation method indicates d34S values from -5.48ë to +5.53ë. The geology, alteration, ore mineralogy, fluid inclusion microthermometry and sulfur isotope data of the Kyaukpahto deposit are consistent with an epithermal ore deposit model for the deposit. However, the presence of CO2-liquid bearing fluids and the detectable CH4 in the gaseous phase of the fluid inclusions conflict with a typical epithermal origin for the Kyaukpahto deposit. The host siltstone and mudstone sequence, trace element geochemistry, and the disseminated nature of sulfide and gold mineralisation are also common characteristics of a sedimentary rock-hosted gold deposit, and these features may indicate a Carlin-like affinity. An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

The activiltion of sphalerite with electrolytically generated copper ions from a copper electrode instead of the usual practice of the addition of copper sulphate was studied in the laboratory. A large surface area of copper was provided by lining three sides of a bench flotation cell with copper sheeting. The lining was connected to the positive terminal of a low voltage d.c. source, and the cell impeller to the negative terminal.Sphalerite was effectively activated by this arrangement and was subsequently floated using xanthate as the collector.Flotation results comparable to those obtained with 1 lb/ton CuS04.5H20 (0,255 lb/ton copper) were obtained using 0·1062 lb/ton of electrolytic copper and 0·488 kWh of electrical energy. The wastage of copper due to the formation of insoluble precipitates was found to be dependent on the length of time the current was passed. Maximum current was passed for the shortest time to minimize wastage.

Jan 1, 1973

The Mining Act (1992) and the Petroleum Act (1980) provide for the Government of Papua New Guinea (PNG) to take up equity holdings in mining and petroleum projects. The price the Government pays for its share is based on the historical cost of exploration and development on the project to the date of government equity acquisition. The equity level to be acquired is not fixed and ranges up to 30o for mining and up to 22.5s for petroleum at the discretion of the Government of the time.The objective of this paper is to examine the pros and cons of State equity holdings in PNG from the point of view of both the State and the developer. Using an economic model of the PNG mining taxation system an assessment is made of the effective return on investment received by the State from such equity holdings. The results are compared with government revenues from other taxation measures.

Jan 1, 1994

By M L. Leybourne

In 2012, in response to an increasing potential unfunded liability, the Western Australian Government passed the Mining Rehabilitation Fund Act 2012. The intent of this Act was to introduce an annual levy on tenements covered under the Mining Act 1978 based on the area of disturbed land. The fund generated from these levies could then be used to rehabilitate mining sites where all other options to ensure rehabilitation had been exhausted. The fund could also be used to rehabilitate abandoned sites or features which, in Western Australia, number over 10 000.The Mining Rehabilitation Fund (MRF) was implemented on 1 July 2013 for an initial voluntary year. It becomes compulsory on 1 July 2014. By the end of March 2014, nine months into the voluntary period, over $6.5 million had been paid into the fund. The incentive for tenement holders to voluntarily enter the fund was the opportunity to have unconditional performance bonds held against their tenements retired. While there will be circumstances where bonds will continue to be applied, it is the State Government’s intention to retire most of the bonds.The MRF has received mostly accolades from industry and companies that have entered. Most have found the system easy to use. The MRF was also cited as a reason for Western Australia’s improved position in the Fraser Institute’s annual survey of mining jurisdictions. Work is now starting on processes to select priority abandoned mines for rehabilitation.This paper explains the background to the MRF and its development, and reviews its implementation during the first, voluntary, year. It also discusses how the fund will be managed into the future and what this will mean for both abandoned mine features across Western Australia and any future abandoned mine sites.CITATION:Leybourne, M L, 2014. Ensuring rehabilitation into the future – The Western Australian Mining Rehabilitation Fund, in Proceedings Life-of-Mine 2014 , pp 441–448 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 16, 2014

This study examines the application of Landsat TM data to the identification of hydro- thermal alteration in the arid terrain of the El Salvador region of north Chile. Numerical reflectance values were extracted from the digital Landsat TM data for a variety of rock surfaces, including four parts of the El Salvador gossan, for each of six spectral bands. These reflectance values were analysed statistically in order to select the three spectral bands, combined as a colour composite image, that are most efficient in discriminating different varieties of alteration and for general geolog- ical interpretation. The most cost effective com- posite image for this area is a combination of bands 1,4 and 7 as the blue, green and red components respectively, with simple contrast enhancement. This image is superior to some much more expensive enhancement techniques and allows unambiguous identification of areas of hydrothermal alteration larger than about 50m. The display includes a practical guide to the use of Landsat TM imagery for volcanic gold Exploration.

Jan 1, 1987

By P Albert, S Crispin, J Hertrijana

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. The Martabe gold mine is Indonesia’s largest precious metals-only producer and is also one of few significant hard rock mine developments in the past 15 years. Martabe is located on the west coast of the island of Sumatra in the North Sumatra province. The mine commenced operation in mid-2012, producing over 280 koz of gold and 1.5 Moz of silver in its first full year of production.Martabe consists of a cluster of six currently identified high-sulfidation epithermal deposits. The deposits lie in a north–south corridor with an approximately 8 km strike length and 1.5 km width. The total Measured, Indicated and Inferred Mineral Resource Estimate of the deposits is currently 8.2 Moz of gold and over 75 Moz of silver.The exploration program at Martabe has added more than 2 Moz of gold and 15 Moz of silver to the Mineral Resource estimates (Measured, Indicated and Inferred categories) since G-Resources acquired the project in 2009. This has been achieved at an average cost of US$17 in exploration expenditure per ounce of resource added, which includes helicopter-supported drilling programs in rugged forest terrain.The factors that led to this exploration success at Martabe include: in the first instance and most importantly, recognition of the geological potential of the mineralised system continually updating and improving ‘orebody knowledge’ and applying new ideas to the exploration program ongoing engagement and consultation by world professionals with geological expertise in similar systems ongoing executive management support for the program the high quality of work completed by previous owners a strong focus on quality control, staff development and operational safety, with the JORC Code (in particular Table 1 of the Code) as the underlying basis for quality control continual and positive engagement with government, community and other external stakeholders.This paper will discuss in detail the first of these two factors. It is important for the modern exploration team to recognise that mineral potential on its own is not sufficient for exploration success, so this paper will touch on the other factors as secondary but crucial considerations.CITATION:Crispin, S, Hertrijana, J and Albert, P, 2015. Exploration success at the Martabe gold mine, Indonesia, in Proceedings PACRIM 2015 Congress, pp 567–572 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

By C Woodfull, S Munroe

Geological uncertainty is reduced by improved understanding of the relationship between regional-scale geological basement features (structure, composition, depth) and known local structural risk (such as recognised structural hazards at the mine). Coal mining and exploration entities can be more efficient and effective in managing geological risk at a range of scales. A more efficient and effective performance in forward interpreting and managing geological risk will result in a more efficient and effective exploration and also incremental or even significant mining cost improvements. In order to improve the understanding of basement features, a new 4D regional structural/basin framework for the Sydney Basin and the eastern part of the Gunnedah Basin has been constructed to provide primarily coal exploration and mining with a more integrated geological framework for ongoing subregional to mine-scale geological risk based studies. The model has been developed from a range of available regional geophysical and geological datasets, of variable detail and reliability, which have been brought together to generate a more robust structural and tectonic model than could be generated with any one single dataset. An initial regional structural model for the Sydney Basin was constructed in 2003 and an update to the model was released in 2005 (SRK Consulting, 2003; 2005). The development and ongoing refinement of the model was undertaken with financial and data support from a number of coal mining industry, gas exploration and government organisations. Prior to, and following the development of the regional structural/basin model and associated Information Base, a number of more area-specific studies have been completed, using the æbasement upÆ assessment approach. The methodology for developing comprehensive structural models, from the basement up, is outlined. The approach can be applied at a country-wide, regional or lease area scale. Case examples of where this approach has been used as an effective and efficient method in improving geological certainty and as a predictive tool to help manage geological risk are also presented.

Jan 1, 2006

Boliden's Aitik open pit mine located in northern Sweden, will expand yearly production from 18 to 36 Mt of copper ore during 2010. The expansion includes a new concentrator located 3 km off the pit, two new apron feeder crushers connected to the ore storages and concentrator with conveyors at a total length of 7 km. The concentrator has two lines with autogenous grinding mills and flotation each with a capacity of 18 Mt. Consequently the mine operation has to be expanded. To achieve this, there was several parallel processes ongoing; investments in new equipment, reorganisations, improvement projects in maintenance and productivity. The Aitik 72 project was started to coordinate productivity and mine planning activities. Initially the long-term strategic mine plan called for a total movement of ore and waste to increase from 40 to 72 Mt but has today increased to 89 Mt. Productivity projects have been focused on load and haul activities such as fuel economics (Renstr÷m, 2007), effective utilisation of trucks partly by increasing manning levels, improved dispatch and shovel utilisation focusing on optimal use of loader/truck fleets. The eco-driving projects previously reported have reduced fuel consumption significantly. This project is also a productivity project, as part of the fuel savings comes from minimising idle engine hours due to queues, break-downs, operator shift changes, etc but also from under and overloading. Effective use of truck fleets, ie transport of material, loading and dumping, thus excluding non-productive engine hours has been an essential motivator when deciding the size and number of new trucks required. This has resulted in a reduction of the investment with at least one but maybe two trucks. A third major project was to optimise shovels together with truck fleet by improving short-term, up to two weeks, detailed planning of drilling and shovel activities. Daily scheduled breaks for maintenance as well as planning of shovel utilisation, down to shift level are included in the production plans. KPIs and online production reports, based on real-time monitoring of drill rigs, shovels and trucks, have been an essential tool used regularly to engage and motivate mine production personal and information reporting to management. Several projects have already reached their goals. The projects will continue throughout 2010 to ensure that productivity targets are met.

May 1, 2010

By Ueki S

Underground coal gasification (UCG) is a promising process for obtai- ning energy from coal, which is either unmineable with current mining techno- logy or uneconomic to recover, using conventional methods, in the present energy market situation. There are several coal fields, which could become new coal reserves, if the UCG process were successfully applied. In the 1960's Japanese researchers made a number of basic studies and field tests into UCG, although not all of them produced favourable results. This paper reviews Japanese research on UCG. This includs basic studies into coal gasification using a small, tube reactor fed by air and oxygen, and also large scale model stu- dies(reactor size of 8.Om x 2.4m x 1.5 m). Field test results from Akabira colliery in Hokkaido and a feasibility study of power generation using UCG from a coal field in Hokkaido are also Presented.

Jan 1, 1987

By Marshall GA, Dickerson AW

The efficient operation of large haul trucks in large open pit mines requires an economic trade off between the haul route quality, the haul truck payloads and the level of haul truck reliability. This paper describes an investigation into the relation- ship between haul route surface quality and the level of structural reliability of a haul truck main frame. An instrumentation system for unattended recording of data on a haul truck operating normally in a mine and com- puter based analytical procedures were developed and used to identify which road segments contribute significantly to fatigue cracking at various sections of a haul truck main frame. INTRODUCTION In many open pit mines there is exten- sive use of large haul trucks to move over- burden and minerals. In most open pit hard rock mines, both the overburden and mineral ore are moved by large rear dump type haul trucks. Similar haul trucks are also widely used for coal overburden and mine site coal haulage operations in New South Wales, South Australia and Western Australia. Large bottom

Jan 1, 1982

The past decade hap seen revolutionary advances in com-munications and information-handling techniques which have been stiriulated by "cold war" military requirements and by, current programmes for probing into outer space: The tools used in exploration for petroleum and minerals have been improved significantly as a result of this new space age technology and even greater improvements are on the way.Two areas of technical activity have been particularly fruitful in enhancing the effectiveness of exploration, methods. These are (1) The development of new approaches, based on information theory, for extracting signal from noise more efficiently than before, and (2) The use of high-speed digital computers for storing and processing all kinds of exploration information, not only geophysical but geological as well.In seismic prospecting, use of information theory has led to new techniques such as time-domain filtering, wave-number filtering and correlation methods which have made it possible to obtain usable reflection data from areas which were previously considered NR. Complex playback and other data processing facilities have been developed to apply these approaches.

Jan 1, 1963