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THE area dealt with in this paper is included within a radius of about 3 miles of the Poimena township. Several thousand tons of tin have been won from this field, and probably £200,000 spent in exploiting it.PREVIOUS LITERATUREThe field has been reported on by Government geologists on four occasions and several ,articles on it have appeared in the mining journals. The work done by Government geologists is summarized below:-"Report on the Blue Tier Tin Mining District and its Tin Deposits", 1886.Speaking of the tin-ore occurrences, this paper states:-"In the primary granite the lodes of tin ore occur, also dykes and belts of more recently obtruded porphyries. The really valuable metalliferous deposits may be classified as follows :-1. Lodes (of which the Lottah mine is typical).2. Dykes- (a) Indurated or hard (as shown by the formations at the Anchor and Cream Creek mines). (b) Soft (eg Hayley's Lease).

Jan 1, 1912

By Gregory M. Dexter

Recent litigation in Pennsylvania between three coal-mining companies and a private water company resulted in the payment by the coal companies of the equivalent of about $500,000 to buy a new water supply to replace that which had been damaged by acid drainage from strip mining. An investigation of the relevant facts indicates that the water could have been treated by spending about $40,000 on equipment and $15,000 yearly for chemicals, labor, and power until the contamination could be reduced about 80 pct. The water company's supply, furthermore, had deteriorated largely by reason of dry weather before stripping was begun by the coal companies. Payment to the water company should not have exceeded $300,000 and could have been as low as $100,000. Strip mining of coal is common in Pennsylvania. The most important objection to it in Pennsylvania is generally acid pollution of runoff water. An outline of the methods, therefore, that could be used to reduce such pollution, to compare acid-contaminated waters, and to treat such waters to make them satisfactory for public and industrial use is worth-while. The watershed of the West P~M Water Co. covers about 4.5 square miles, 20 miles west of Pittsburgh, and has two 90,000,000 gal reservoirs sup- plying about 1,300,000 gal daily for public and industrial use of which 450,000 gal daily are for two railroads. The pollution arises from weathered derivatives of typical "Coal Measures"

Jan 1, 1949

The Tasman Orogenic Zone is regarded as a single metallogenic province (the Tasman Province) with four SUb-provinces corresponding with its major tectonic components: the Lachlan, New England, Hodgkinson.and North Queensland orogenic provinces. Within the Tasman Province there are four main ore-rock associations.These are1. manganese and iron with sedimentary and basic volcanic rocks,2. zinc-lead-copper and copper with intermediate-acid volcanic sequences,3. minor chromium, platinum, and osmiridium with ultramafic complexes, and4. tin, wolfram, gold, and copper with syn- and posttectonic granitic intrusions.Whereas the ores of ultramafic and volcanic associations form geographically-restricted metallogenic districts, the ubiquitous granitic ores may be subdivided into twenty-one districts that cover almost the entireOrogenic Zone. The Tasman Province is notably lacking in uranium ores and Mississippi Valley-type deposits.There is a distinct tendency for ores of each association to be progressively younger to the east and north, thus paralleling the progressive growth and stabilization of the Zone. Similar ore-rock associations are present in repeated phases of mineralization from the Cambrian to the Permian-Triassic, reflecting the essential homogeneity of the Tasman Province, and the similarity of the successive tectonic cycles.

Jan 1, 1972

By Gordon] [Reavis

Halliburton Services and Brown & Root have developed a unique foundation system that blends oilfield and construction technologies to construct deep foundations which offer significant advantages across a variety of soil profiles. This highly efficient system is being developed to meet the construction industry's needs into the 21st Century. Based on a concept initially introduced to Halliburton Services by V.L. Schellhorn in 1987, Halliburton combined their existing cement slurry mixing and pumping technology with oilfield drilling practices and a new tool design to field test the viability of the concept. Results looked encouraging, and Halliburton asked it's sister company, Brown & Root to evaluate and further develop the process. With Brown & Root's knowledge of the construction industry, the original concept has developed into a viable and efficient foundation construction system.

Jan 1, 1993

By D Hill

In the Ngakuru area zeolite deposits occur in late Quaternary lacustrine vitric tuffs of the Ngakuru Formation and two of the deposits are being mined. The Ngakuru Formation overlies the Ohakuri Ignimbrite dated at c. 240 ka, and is overlain by younger alluvial sands and gravels. Individual zeolite deposits contain 50 - 80 per cent zeolite over a thickness of up to 45 m in thinly stratified vitric tuffs and are localised along NE-trending normal faults. Glass shards in the tuffs are replaced by the silica-rich zeolites mordenite and clinoptilolite. Amorphous silica (opal A), opal-CT, Kfeldspar and smectite are also present. The zeolites and other minerals are very fine grained (<10 8m), with open meshes of crystals that result in high porosities (52 - 70 per cent) in mordenite-rich tuffs. Zeolitic tuff samples typically have cation exchange capacities of 80 to 110 meq/100 g and internal surface areas of 25 - 58 m2/g, which combine to give high liquid and odour absorption capacities. The first zeolite deposit (Mangatete) was found in 1992, and this and the Twist Road deposit are worked by quarry benching into the side of hills. The zeolitic tuffs are dried and crushed to produce a variety of products including adsorbents for soaking up oil/chemical spills and animal wastes, animal feed supplements, water treatment, and sports turf and slow release fertiliser. The Ngakuru zeolite deposits formed at shallow depth (<100 m) along fault zones from reaction of glass-rich tuff beds with groundwater-diluted geothermal water during the late Quaternary, and are as young as 8500 yr BP from 14C dating of plant material in sinter associated with the Mangatete deposit.

Jan 1, 2005

By H Thanasekaran, J Kohmuench, B Seaman

To achieve an efficient separation in the flotation process, valuable particles need to be selectively segregated from the gangue while utilising a minimum number of flotation stages. TodayÆs existing flotation technologies are effective for fine particle size classes; however, limitations due to particle buoyancy and bubble-particle detachment restrict the effectiveness of traditional flotation approaches on coarser particles. As a result, flotation circuits are generally configured to process only fine particle size classes in order to maximise recovery in the primary stages. Eriez has invented a novel flotation technology, the HydroFloat, which overcomes these limitations by carrying-out flotation in a dense, fluidised-bed medium allowing for the recovery of coarse particles (>0.250 mm). Over the last 15 years, this technology has been successfully applied to industrial minerals with several full-scale units installed to recover particles up to and exceeding 3 mm diameter in primary flotation circuits. This paper includes discussions on the history of this technology, process theory, existing applications, and a review of recent sulphide-based laboratory test work conducted for Newcrest mining and others. Benefits of this approach, such as improved recovery, low energy consumption and reduced reagent addition will also be reviewed.CITATION:Kohmuench, J, Thanasekaran, H and Seaman, B, 2013. Advances in coarse particle flotation - Copper and gold, in Proceedings MetPlant 2013 , pp 378-386 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 15, 2013

By A. J. Williams

"Conventional base metal milling practice normally consists of crushing, grinding and cyclone classification followed by flotation. It is the authors' belief that the commencement of flotation after cyclone classification leads to inferior metallurgical results and that implementation of flotation of grinding mill discharges can result in increased recovery due to reduced overgrinding, reduced activation of contaminating minerals and improved dewatering circuit results due to the production of coarser concentrates.The concept of recovering minerals from the discharge of grinding mills is not new! Gold concentrators have utilized jigs and flotation cells while iron ore plants have employed magnetic separators to recover gold and magnetite respectively from the discharge of grinding mills. More recently, a Reichert cone has been used to recover sulphide and oxide base metal minerals from screened rod mill discharge. 1To the authors' knowledge, the first application of flotation of base metal minerals from the discharge of a production plant grinding mill was at the Lake Dufault concentrator of Corpor'1tion Falcon bridge Copper. Located 10 miles north of Noranda, Quebec the Lake Dufault concentrator commenced operations in August, 1964.The installation of flot11tion cells in the Lake Dufault grinding circuit proved so successful that an identical system was installed in the Manibridge concentrator of Falconbridge Nickel Mines Limited. Located 90 miles southwest of Thompson, Manitoba the Mamibridge concentrator commenced operations in June, 1971 and due to exhaustion of economic ore reserves discontinued production in May 1977."

Jan 1, 1984

By M. E. Poad, J. K. Whyatt, T. J. Williams

Researchers at the U.S. Bureau of Mimes monitored rock mass response to mining of an experimental underhand longwall stope in Hecla Mining Co.'s Lucky Friday Mine, Mullan, ID. This stope design, the Lucky Friday underhand longwall (LFUL), was proposed as a means of controlling rock bursting while also allowing increased mechanization of mining operations. Instruments were specifically manufactured to monitor three geomechanical factors (backfill performance, ramp stability, and rock mass response) that directly affect the success of stope design. Despite considerable difficulties with instrument installation and survival in the harsh mine environment, especially within the stope fill, sufficient information was collected to suggest that the LFUL method was successful in achieving project goals. This conclusion, in addition to favorable economic and operational evidence, led the mine to adopt the method throughout the mine. Indeed, this study and mining experience suggest that underhand longwall mining could be considered a feasible mining method for rock-burst-prone ground throughout the Coeur d'Alene District. Further Reports of Investigations (RI) in this series present in-depth analyses of the effects of backfill on rock bursting and calibration of a stope numerical model.

Jan 1, 1992

[Adams, Douglas K General Electric Co., P.O. Box 2331, Denver 1, Colo. Alger, Van Kaiser Steel, Sunnyside, Utah Allan,-Andrew Thompson Creek Coal & Coke Corp., Glenwood Springs, Colo. Allen, Earl W Mine Safety Appliances Co., 257 Rio Grand St., Salt Lake City, Utah Allen, John P Development & Resources Corp., 50 Broadway, N. Y. 4, N. Y. Allen, Thomas Chief State Coal Mine Inspector, State Services Bldg., Denver, Colo. Alston, George L Mine Safety Appliances Co., 201 N. Braddock, Pittsburgh 8, Pa. Anderson, Nephi W Book Cliffs Coal Co., Dragerton, Utah Anderson, W. J Texaco, Inc., 845 N. 5th E., Price, Utah Ankeny, Marling J U. S. Bureau of Mines, 5308 Roosevelt St., Bethesda, Md. Archer, Bryon J., Jr Peabody Coal Co., 421 Glenwood St., Grand Junction, Colo. Arentzen, E. M Lee-Norse Co., Charleroi, Pa. Arentzen, L. E Lee-Norse Co., 2975 18th St., Boulder, Colo. Artis, Cliff E Big Horn Coal Co., 247 Sherman Ave., Sheridan, Wyo. Atchison, Lee Atchison Construction Co., Drawer D, Aztec, N. Mex.]

Jan 1, 1963

By E. Eccleston

The ConRoast process for the production of platinum group metals involves the use of a fluidized bed reactor for the removal of sulphur from ore concentrates by roasting prior to smelting in a DC-arc furnace. Test work was carried out in 2007 at Hazen Research in Golden, Colorado to provide the data necessary for a commercial roaster to be designed by Technip. This paper discusses the rationale behind the test work, the goals for calcine composition to be used as smelting furnace feed, the results of various roaster operating parameters in terms of calcine composition (particularly residual sulphur and the fate of trace elements), and the impact of the results in terms of a commercial roaster design.

Jan 1, 2009

By Bruce Geller

The 2005 Prospectors and Developers Association of Canada (PDAC) convention continued the upbeat mood found in 2004. The global mining industry is booming due to higher commodity prices in nearly every sector. Other factors include low commodity inventories, China’s strong resource demands, the weak U.S. dollar, the very strong Euro, global uncertainties, an almost overripe investment climate for natural resources and the highest mining exploration budgets in seven years. Even unglamorous commodities, like iron, uranium and zinc, received copious attention in talks, the investors’ exchange, the core shack and in certain hospitality suites. The following impressions were gathered at the convention and enhanced by conference handouts and some abstracts that are available on the PDAC’s Web site, www.pdac.ca. At least 119 papers were presented, almost twice last year’s number.

Jan 1, 2005

This paper considers three aspects of cemented fill practice and research in Mount Isa. Firstly, an account is given of the use of Portland cemented hydraulic fill, considering mainly the role and specifications of the fill used but including û brief description of fill preparation and placement. Data resulting from a Portland cemented hydraulic fill sampling, curing and testing campaign covering about 18 months of operating practice are presented, analysed and discussed. These yield information indicating the mode of operation of a fully-automated fill preparation station, as well as a means of comparing field and laboratory strength results. A technique with potential for use as a fill quality control without actual strength testing is also described. Results of a fill research program conducted by the author in Mount Isa since early 1968 are presented, involving both Portland cemented hydraulic fill and alternative, cheaper, additives for cementing hydraulic fill.

Jan 1, 1971

By M. G. Dellow, D. W. Hendriks

"In early 1988 the decision was made by Noranda Minerals Inc. to install pressure filters at the GECO mill to replace the vacuum disk filters and bunker-C fired rotary kiln dryers. Two filters were installed, one for copper concentrate and one for zinc concentrate. Completion of the project was scheduled for the third quarter of 1989. The filters were made operational in October 1989. Some work remains to be done yet on loadout conveyors for total project completion. Capital expenditures for the project have been approximately $2,700,000 to date. The paper describes the selection criteria for the filter, the installation, startup and associated problems.1. INTRODUCTIONThe filter model chosen for the project was the Verti-Press model VP-50-6(7) (Figures1 ,2 and 3) by Filtra Systems of Farmington Michigan, USA. The decision to purchase the Filtra Systems filter was based on gaining familiarity with a different, mechanically simpler pressure filter than the Larox design and to a lesser extent a necessity for repairs to the the disc filter, rotary kiln dryer system used at the GECO operation for its' copper and zinc concentrates. The fact that it is manufactured in North America was an important consideration. The same basic principles of pressure filtration as the Larox machine are used but the implementation is quite different and somewhat simplified with some interesting innovations. 2 filters were installed to allow direct and immediate comparison of the same machine on both fine and coarse materials. Copper concentrate is reground for cleaning on the flotation circuit while zinc is not. Screen analysis of composited samples of concentrates for 1988 indicated that expected copper concentrate would be approximately 66% minus 400 mesh and zinc 50% minus 400 mesh (Tables 1 & 2).The filter is composed of six horizontal chamber module layered vertically and held together in a frame by 1 O large bolts; torqued down to 4000 ft-lbs. 6 individual belts are used; each with its own drive system. The belts themselves are of a 3 piece design with a filter cloth portion, a support belt and a rubberized intermediate portion. They are held together with steel clipper lacings. A basic description (1) of the filter operation is as follows. ""The horizontal filler chamber is closed by hydraulically pressurizing seals across each end of the filter chamber to 200 psi. The feed pump then pumps slurry into the filter chamber. Suspended solids are retained on the filter belt and the filtered solution drains into a lower drip tray and flows from the filter by gravity. At the end of the filtration or feed cycle, a rubber diaphragm in the filter chamber is pressurized hydraulically to 100 psi pressure. This removes all free liquid from the filter chamber and the filter cake. After the diaphragms are retracted the filter cake is blown with compressed air to remove any residual cake moisture. The seals are then retracted and the belt is advanced to discharge the filter cakes. During the cake discharge the belts are washed with a spray header located at the drive end of the filter. The belt assemblies move one (1) complete revolution during the cake discharge cycle. The cycle automatically repeats until the filter is shut down by the operator."

Jan 1, 1990

By Ivette E. Torres

Aruba, formerly a. part of the Netherlands Antilles, separated on January I, 1986, and became an autonomous part of the Netherlands. Full independence of the island from the Netherlands is scheduled for 1996. In this chapter, however, Aruba's statistics are included with those of the Netherlands Antilles. Tourism continued to be the main industry of the island, which continued to depend heavily on imports, mostly from the United States. During the year, the Government was preparing legislation to regulate the exploration of oil deposits in the relatively shallow sea around Aruba.

Jan 1, 1989

By A. J. Davidson

A Cu-conducting solid electrolyte was used to develop the sensor. Instead of measuring the potential across the electrolyte from the reference material to the Cu-containing phase, a potential was applied and the stable current measured. This gave reasonable readings for copper-tin alloys, which agreed with the theoretical calculations, but was less satisfactory in the case of mattes because the surface area of electrolyte presented to the matte phase varied from sensor to sensor. To overcome this problem the potential was applied, the current was measured and then reversed and remeasured and the ratio of the currents was calculated. The current ratio is shown to be independent of the resistance of the electrolyte and the surface area of the electrolyte offered to the melt, but strongly dependent on the activity of the copper

Jun 21, 1905

Traditionally, capital costs of major resource development projects have been estimated as a single amount to which a percentage accuracy has been assigned based on the method of preparation of the estimate, that is, on the amount of information available to develop the estimate.However, there is a growing recognition of the importance of a probabilistic approach to capital cost estimates, and of a more rigorous calculation of estimate accuracies and of the presentation thereof. Accuracies can be expressed with more certainty as a percentage of the estimate amount where the percentage represents one standard distribution on the probability curve for the capital cost of that specific project. Thus confidence levels can be stated for various estimated amounts - for example, it can be stated that there is an 85% chance that a stated amount will not be exceeded, or a 90% certainty that a (higher) amount will not be exceeded. Moreover, the right skewness of the probability distribution curve for most projects can be readily recognised and reflected in the evaluations. This enables senior executives and board members to have a clearer understanding of investment uncertainties, and the possible magnitude of commitments.

Jan 1, 1990

This paper describes new research and development currently being undertaken by the CSIRO Mining Technology Group to advance the automation capability of continuous mining equipment in underground coal mining operations. The effort aims at increasing the overall rate of roadway development as well as providing a safer working environment for underground mine personnel. The activity is funded by the Australian Coal Association Research Program (ACARP) and forms part of a larger underground development initiative, known as the CM2010 project. The CM2010 is managed via a consortium of leading mining industry representatives through the Roadway Development Task Group (RDTG). The Task Group has identified three research areas requiring new development in order to realise the CM2010 project objectives: self-guiding (autonomous) continuous miner capability, an enhanced drilling and bolting process and improved mesh deployment. CSIRO's primary role in the CM2010 project is in the development of the autonomous continuous miner guidance capability.This paper reports on outcomes achieved at the half-way mark of a three year research and development project. It details the technical developments undertaken towards demonstration of a 'self-steering' capability to enable a continuous miner to automatically maintain a given mining heading and mining horizon under production conditions. A primary technical requirement of this automated functionality is the means to accurately determine both the location and orientation of the continuous miner in real-time. Testing and validation of the guidance system solution has been implemented using a combination of an instrumentation-grade inertial navigation unit and radar technology. Comprehensive performance evaluations have been conducted using a scale skid-steer mobility platform known as the Phoenix. Results achieved to the present stage of the project are highly promising and suggest that an automated self-steering functionality is achievable under production conditions. This new outcome represents an important move towards implementing a step change improvement for future underground roadway development.

Dec 6, 2010

By James D. Noll, Eileen Birch

In a previous study, the e?cacy of commercial and prototype impactors for sampling diesel particulate matter (DPM) in coal mines was investigated. Laboratory and ?eld samples were collected on quartz-?ber ?lters and analyzed for organic and elemental carbon. Coal dust contributed a minimal amount of elemental carbon when commercial cascade impactors and prototype impactors, designed by the University of Minnesota (UMN) and the US Bureau of Mines (BOM), were used to collect submicrometer dust fractions. Other impactors were not as e?ective at excluding coal dust. The impactors evaluated in that study were either not commercially available or were multi-stage, expensive, and di?cult to use for personal measurements. A commercial version of the BOM impactor, called the DPM Cassette, was recently introduced by SKCs. Tests were conducted to evaluate the performance of the DPM Cassette for measuring diesel-source elemental carbon in the presence of coal dust. Bituminous coals from three mines in two di?erent coal provinces were examined. The dust particle diameters were small and the coal dust contained a high percentage of carbon, there by giving a worst-case condition for non-anthracite coal mines. Results for the DPM Cassette were essentially identical to those obtained by the BOM impactors in a previous study. At a respirable coal dust concentration of 5.46mg m3, which is 3.8 times the regulatory limit, the DPM Cassette collected only 34µg m3 of coal-source elemental carbon.

By L Avalos, F Melo Miranda, J Misle, M Ingwersen

"Los Pelambres, majority owned by the Chilean company Antofagasta Minerals, is one of the leading producers of copper and molybdenum in the country. It is located high in Andes Mountains, over 3000 metres above sea level, 316 km from the nation's capital, Santiago.The maintenance service supplied to Los Pelambres over the past 13 years has evolved to the point that FLSmidth now provides an integrated service crucial to the management of their customer's assets. The contract initially involved specialty mechanical, electrical and instrumentation maintenance and has developed to encompass maintenance planning and plant control systems.The integrated partnership has delivered excellent results in the areas of improved availability, reliability and return on investment. The operation is now amongst the industry leaders in plant availability.The integrated maintenance service has delivered: An increase in plant availability from 93%, in the first year, to 96.5% today, generating approximately $50 million additional income per year, Quality work procedures, Process and equipment improvements, Major shutdown planning involving more than 700 personnel, 6000 parts and over 2 000 discrete activities.The ongoing success of the partnership requires a high level of understanding between both companies. A commitment to maintain a long term sustainable relationship, based on a ""win - win"" culture, is the key to this success. In this regard Los Pelambres has been a pioneer in establishing and developing such relationships.This case study will share the lessons learnt, the measures taken to improve performance and the best practices adopted during the 13 year evolution of the maintenance service partnership.CITATION:Misle, J, Melo Miranda, F, Avalos, L and Ingwersen, M, 2013. Integrated maintenance services at the Los Pelambres Mine in Chile - The lessons learnt and best practices developed from a long-term sustainable relationship, in Proceedings MetPlant 2013 , pp 296-331 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jul 15, 2013

By Weber P, Sneyd S

The total world steel production in 1998 amounted to approximately 780 000 000 t. The share of electric steelmaking was in the range of 35 per cent and is expected to increase further to over 40 per cent of the world's production within the next ten years. As electric steelmaking is primarily based on the use of scrap and as it is progressing more and more into higher steel grades the need for low-residual metallics will become increasingly important. Consequently, the demand for scrap substitute material will increase, reflected in the world wide spate of interest for DRI (Direct Reduced Iron) and HBI (Hot Briquetted Iron). The increased significance of DRI/HBI as a substitute for steel scrap has obviously emanated also from its comparatively lower and more predictable costs per ton and definable chemistry. In 1998 already 37 million tons of DRI/HBI were globally produced.

Jan 1, 1999