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Mount Read is 'situated in the county of Montagu, on 'the west coast of Tasmania, about 20 miles inland from. Remine in an easterly direction, 15 miles northerly from Mount. Lyell, and 30 miles south-east from Mount Bischoff, and is one of the mountains forming the west coast range; it rises to a height of 3890 ft. above sea level.About eleven years ago the first mineral section was taken up on Mount Read by a Hobart company, known as the Mount Reid Silver Mining Company, consisting of 25,000 shares its holding consisted of one section of 80 acres, held under mineral lease. Prospecting was carried on for some months under great disadvantages, as all supplies had to be carried up the mount from Dundas, a distance of nine miles, on men's backs, until a pack track for horses was made.The track rises 2500 ft. in the first five miles, and then falls 200 ft. from that point to the mines, which are at an altitude of 3000 ft. above sea level, and at a point about two miles westward from the summit of the mountain, approximately midway between Mounts Read and Dundas.

Jan 1, 1901

By K. S. Liddell

Ultra fine grinding is becoming increasingly used in the mining industry over recent years. The development of large-scale units for high volume grinding of low value materials and concentrates has opened up new areas of economical metal extraction. The ability of stirred vertical mills to produce very fine particles with high surface areas, is providing mine operators with novel extraction possibilities within gold concentrate regrind for Biox or leach feed, Activox autoclave feed preparation and lime slaking operations. The paper will review design, operational and maintenance aspects of ANI-Metprotech stirred vertical mills, comparing these to tower mills, horizontal bead mills and attrition mills.

Jan 1, 2001

Flotation of Phosphate Gangue from Magnetite Fines - Non-Ionic Surfactant as Atrac Collector Modifier

Sep 13, 2010

By Choon Kooi Quan

Water availability is essential for mining and minerals processing. To provide government and industry with recent data for water use planning and management, the Bureau of Mines canvassed a number of U.S. producers of nonfuel minerals to determine their water use in 1984. Data were analyzed and compared with previously published data in order to examine historical trends in water utilization in the nonfuel minerals industry and to estimate water requirements in the year 2000. Total water use in the domestic nonfuel minerals industry during 1984 was estimated at 2,267 billion gal, of which 571 billion gal was new water and 1,696 billion gal recirculated water. The largest users of water were the phosphate rock, iron ore, copper, sand and gravel, and crushed stone industries, together accounting for almost 90% of total used. More than one-half of all water was used in Florida, Michigan, and Minnesota. In the year 2000, total water use will amount to an estimated 2,679 billion gal, of which 810 billion gal will be new water and 1,869 billion gal recirculated water. Most of this water would be used in producing the foregoing suite of minerals,

Jan 1, 1988

By Bruce D. Hansen

For many years, Newmont has focused on improving its operations. After the merger between Newmont and Santa Fe Pacific Gold, Newmont created synergies of more than $50 million a year in Nevada. This was done primarily through optimal ore movements and consolidation of various functions. During the current period of low gold and copper prices, Newmont has refocused its efforts on efficient operations worldwide. At its mine facilities in Nevada, Newmont has used a combination of several strategies to decrease the costs of operations and to increase profitability. These include computer technology, optimal use of infrastructures, procurement strategies, functional consolidation, enhanced mine planning and several available metallurgical processing options.

Jan 1, 1999

By Javier Rodriguez

Adaptive re-use of existing structures in urban environments has become very common due to lack of available space in our cities and requirements for increased structural capacity. Often, it involves retrofitting existing foundations to support increased loading. In such cases, Engineers face the need to review existing deep or shallow foundations for their true load carrying capacities in order to determine the required magnitude of retrofit work, if any. To accomplish this, the engineer must track down and cull through the existing construction documentation to determine what was actually constructed, complete an investigation to confirm these conclusions, possibly sample the foundation elements for strength properties, and on occasions complete non destructive or full scale load testing of indicator elements. This paper describes the typical procedure followed by the authors for design of retrofit schemes for existing buildings in the Washington DC metropolitan area. Three case histories are presented that illustrate various issues encountered during design.

Jan 1, 2006

By P. G. Flood

A simplified conceptual model shows how the arc flank to arc fringe areas adjacent to ignimbritic centres form a prospective zone for natural zeolites. Large alkaline lakes that serve as the repository of voluminous ash-fall tuffaceous material provide the ideal chemical setting for pervasive alteration of silicic glass to zeolites. The unusually old age of the Escott deposit demonstrates that any silicic volcanic province that contains low-temperature, unmetamorphosed sequences is a potential zeolite exploration target and that age should not be used as a criterion to exclude potential areas. It has also been demonstrated that heulandite and mordenite, formed by diagenetic alteration of silicic glass, do not always change to analcite and albite through the ageing process

Jan 1, 1991

By S A. Myers, T Klein

The Yanacocha mining district is located in the northern Andes of Peru. The project is within the Cajamarca province, 20 km north of the town of Cajamarca and 600 km north of Lima, the capital of Peru (Figure 1). The district encompasses an area of 120 km 2 and is centred on the 78030'west longitude and 7000' south latitude. The project lies at an elevation of 3400 to 4200 masl.

Jan 1, 1999

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Jan 1, 2009

By O A. Cottrill, G A. Oldfield, S B. Nowell

Host-rock û wallrock major and trace element geochemistry associated with epithermal gold mineralisation in the Hauraki Goldfield of New Zealand is poorly documented, even though rock geochemistry is a recognised tool in exploration. Such responses assist in recognition of the regional scale imprint of fossil hydrothermal activity, and indicate targets for detailed evaluation within these alteration zones.   Recent investigation of gold deposits in the Waihi (Gladstone), Golden Cross (Empire), Thames (Waiotahi) and Coromandel (Tokatea) areas indicate enrichments of Au, As and Sb in the andesitic wallrocks hosting mineralisation. Of the other elements examined, Si, K and Rb are enriched, and Na, Ca, and Sr are depleted at all deposits. These trends are best developed in the vicinity of veining. In deposits with clay alteration dominating (Waiotahi and Tokatea) there is also depletion of Mg, Mn, Zn and Cu. Ba and Cr are variably enriched or depleted within different styles of alteration. Base-metal enrichment in the wallrocks is not a feature of Hauraki deposits.

Jan 1, 1990

By W. H. Somerton

Many oil-producing formations contain significant amounts of clay. Because of the large surface area and reactivity of such surfaces, the response of the formations to various recovery processes may be dominated by the reactions of fine-grained minerals, including clay minerals, in the formations. Thus, the success or failure of enhanced oil recovery (EOR) methods may be controlled to a large extent by the amount and nature of these minerals in the formations to which the methods are being applied. One of the deterrents to the successful application of chemical EOR methods is the loss of chemicals injected into the formation, to non-oil recovery processes. These chemical loss processes include adsorption onto mineral surfaces, chemical reactions with rock and fluids in the formations, possibly leading to precipitation and plugging of the formation, and trapping of chemicals in parts of the rock structure so that they become unavailable for displacing oil. Chemicals that may be injected include surfactants, polymers and caustic solutions which react with organic acids in the crude oil to produce surfactants in-situ. These losses are most pronounced in fine-grained reservoir rocks containing substantial amounts of clays.

Jan 1, 1984

By Poi G, Madgwick J. C, Davis P, Pannowitz D, Cho D, MacKay B, Chan S. M, Varga R. A, Chun U

Periodic dilute sulphuric acid treatment ofstill, batch-fed, molassesenriched, microaerobic, manganese-dioxide-Ieaching microbial cultures led to marked improvements over untreated cultures. Percentage Mn++ recoveries increased (7X), rate of Mn++ formation improved (3X) and yields of Mn++ per molasses use were more economical (5 X). The yield in terms of molasses used improved with decreasing sugar used (eg 1.17 g Mn++/gram molasses at 0.2 per cent molasses (w/v) feed and 24 per cent (w/v) pulp density MnO2 tailings). The most effective Mn++ leaching in terms ofpercentage recovery (97 per cent) and rate ofleaching (46 mg Mn++/day) was at 0.5 per cent molasses (w/v) and 14 per cent pulp density (w/v) MnO2 tailings.

Jan 1, 1986

By Jeffrey A. Schaefer

The Olmsted Locks and Dam project is located on the Ohio River approximately 16.5 miles upstream of its confluence with the Mississippi River. It consists of twin 1200 ft. locks with floating and fixed approach walls, five 110 ft. wide tainter gate bays, a 1400 ft. wide navigable pass boat operated wicket gate section, and a 400-ft. section of fixed weir (Fig. 1). The project will have a total cost over 1.0 billion dollars, and as such is one of the largest civil works project underway in the Corps of Engineers.

Jan 1, 2001

By R. P. Maloney

Since mining operations began in 1900, Government geologists and mining men have periodically recorded the presence of the minerals of mercury and antimony in the extensive gold placer deposits near Flat in the Iditarod district of the Yukon River region, Alaska. No serious effort was made to recover the cinnabar contained in the gold placer gravels, and there is no evidence that veins of cinnabar and stibnite exposed in the placer operations (as reported by the Geological Survey) were ever explored or developed. A large monzonitic intrusive, which is the dominant geologic feature of the immediate area, is believed to be the lode source of the valuable minerals in the placer deposits. In contact with the monzonite are argillite and quartzite, metamorphic products from the Cretaceous shales and sandstones.

Jan 1, 1962

A new porphyry copper gold district has been discovered at Goonumbla near Parkes in central New South Wales. Endeavour 26 North is the largest deposit known to date with a possible resource of 166.4 million tonnes at 0.74% copper, 0.12g/tonne gold and 1.7g/tonne silver, using a cut-off grade 0.3% copper. Mineralisation is primarily bornite in the higher grade zones and chalcopyrite in the peripheral lower grade zones. Most of the copper, gold mineralisation is associated with potassic alteration. Two mineralised quartz monzonite porphyry intrusive stages have been identified and these are related at depth to a large monz- onite stock which may have been the source of some of the mineralisation. On the basis of detailed paragenesis studies, the potassic zone can be divided into three symmetric subzones. The low grade inner potassium feldspar subzone is confined to the later intrusive porphyry. The outer potassium feldspar subzone is the most highly mineralised alteration halo due to the focussed superimposition of two hydrothermal cycles which have overprinted intrusive and volcanic rocks. The fringing biotite potassium feldspar subzone reveals alteration minerals which are developed early in the paragenesis. Fracture controlled quartz sericite alteration with low sulphide content, fringes and, in part overprints the potassic zone. The restricted pipe-like nature of the alteration zones and related mineralisation suggests that Endeavour 26 North is repres- entative of a multiphase focussed porphyry copper gold system.

Jan 1, 1986

In presenting this address I am conscious of the honour that has been paid me in my election to this important office, and I am very aware that I follow, in the position of President, many distinguished men who have led the Institute over the 70 years since its inauguration in Broken Hill in 1893.It is perhaps appropriate tonight that I intend to talk about a metal which recalls the birth-place of the Institute, and is also one with which I have had a direct association throughout the whole of my working career. This metal is Silver.Silver is associated traditionally in everyone's mind with money and silverware, and has always been prized for its natural beauty and elegance. It is today one of the few metals in which world consumption has outstripped production, and the events which have occurred to bring about this situation make an interesting story.In telling this story, I propose firstly to indicate our development as a silver producing country, give an historical review of the metal, trace its use as currency and the factors influencing its price, and then say something of the old and new uses of silver. Finally I shall give some comments on silver production in Australia today.Australia, with 6-5 per cent of the world's output of silver, ranks sixth among the producer countries and over the years has contributed 892.5 million ounces to the world's supply which, based upon production since the discovery ofAmerica, is estimated to have been 22,150 million ounces or nearly 680,000 tons.Although our production appears relatively small by...

Jan 1, 1963

The Mineral Density Separator (MDS) was developed by Mintek to predict mineral separation in a plant, evaluate efficiencies and develop scale-up parameters. This study investigated the influence of particle size on the results of the MDS, the misplacement of material in the MDS and the possibility of replacing heavy liquid float and sink analyses of coal with MDS analyses. Six tests were done with coal of different size ranges. Each MDS layer was subjected to a float-sink analysis whereafter each float fraction was screened to determine the particle size distribution. The results indicated that MDS results represent float-sink analyses when compared to an ash curve. There is some misplacement in the different MDS layers, but this does not seem to influence the results negatively. Keywords Mineral density separator, sink-float analyses, heavy liquid analyses, washability curve

Jan 1, 2006

The paper discusses the special mixing requirements for Metallurgical Plant Design and outlines the problems associated with the agitation in Mineral Processing Industry today. It also covers new applications such as state of the art large leach tanks and backfill for deep mining.

Jan 1, 2004

By P. Schmieder

"The close vicinity of mining companies to other sites that are used for commercial and residential purposes or to areas under conservation as well as the fact that the people become more and more sensitive to emissions have led to a negative attitude towards mining operations in the neighborhood. It is above all the use of drilling and blasting techniques that give rise to objections, in the course of which demands for more environmentally-friendly production methods have been voiced. It is in this context that production methods without the use of explosives are considered as an option. After all, the use of such production methods is the only alternative for some quarry operators. The question is what are the true benefits of these techniques and what is the relation between a possible improvement of the environmental effects on the one hand and the technological potential as well as the costs on the other. It is intended to assess the mining techniques for solid rock in their entirety. This paper will therefore look at the aspects for assessing mining techniques in the context of their environmental impact and the costs."

Jan 1, 2005

By Patrick Polk

For many years, sulfuric acid producers all over the world have been forced to meet ever more strict environmental regulations to reduce SO2 emissions. The sulfuric acid industry has implemented new solutions in order to comply with the new lower SO2 emissions target. Haldor Topsoe (Topsoe) has responded to this challenge by continuously improving the range of VK sulfuric acid catalysts and providing tailor-made catalyst solutions to meet the demands of the sulfuric acid producers for lower SO2 emissions. Reducing emissions through catalysis: requires less capital than installing a scrubber, requires no additional process chemicals, generates no waste or by-product to dispose of. In 1996 Topsoe introduced VK69, a cesium-promoted vanadium catalyst, designed for operation in the pass(es) after the intermediate absorption tower in double absorption plants. The high activity of VK69 allows for a more than 50% reduction in SO2 emissions from existing double-absorption plants. Topsoe currently has more than 110 installations of VK69. To comply with the still more stringent regulations being placed on the sulfuric acid industry to lower SO2 emissions, Topsoe has developed a new sulfuric acid catalyst designated VK-701 LEAP5™. This catalyst was introduced to the market in 2010. VK-701 LEAP5™ is based on a novel technology which circumvents the internal transport deficiencies of existing commercial sulfuric acid catalysts and thereby offers exceptionally high activity in strong, SO3 rich gases. Sulfuric acid plants have used this catalyst to meet emissions requirements lower than previously believed possible with a catalyst only solution. This paper will present examples on how to reduce emissions by implementing a tailor-made catalyst solution using VK69 and VK-701 LEAP5™.

Jan 1, 2014