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By O. A. Ojo, D. L. Chen, N. Zhou, J. Q. Zhang, A. K. Khan

Dual phase (DP) steels are designed to consist of hard martensite dispersed in a relatively soft ferrite matrix, which offers a favorable combination of high strength with good deformability. Fiber laser welding (FLW) is becoming increasingly important for joining advanced materials due to its flexibility and deep penetration. In this study, the microstructure of a dual phase steel, DP980, welded by FLW technique was carefully analysed. Gleeble thermo-mechanical simulation coupled with analytical transmission electron microscopy (TEM) revealed that the FLW process produced significant microstructural changes in a narrow heat affected zone (HAZ) and fusion zone (FZ), which can result in dramatic changes in mechanical properties. This is reflected in the micro-hardness profile obtained across the welded material. The salient phase transitions induced by the FLW, including the formation of new martensite grains in the upper-critical HAZ and FZ, are discussed.

Jan 1, 2014

"Many advances in glass technology and processing are being made and the possibilities for glass as a material in the future appear unlimited. Float glass, glass-ceramics, high-strength sheet and container glass, glass-reinforced plastics, glass for electronic equipment, aerospace glass, glass fibres, glass vehicles, glasses with selective-reflective coatings and glare-reducing glasses, to name a few, provide areas of significance at present and for the future. There appear to be great opportunities, in certain localities of Canada, to develop new sources of raw materials for an expanding Canadian glass industry.New developments in the structural clay products industry have centered around facing brick as a structural load-bearing material, prefabricated brick panels, large-sized units, isostatic pressing of sewer pipe and auto-matic settmg of brick. Fast-firing techniques, using prefired or calcined raw materials, and the development of high-strength products will result in the use of a wider range of raw materials in the whiteware and structural clay products industries.Porcelain enamel, a material used for many years in domestic appliances and for sanitary ware, now is used extensively in architecture, agriculture, water tanks, highway signs and reflectors, and in products where resistance to corrosion-plus-temperature is important. Exotic composites of ceramics and metals, and specialized ceramic coatings applied on metals by various techniques such as flame spray, plasma jet, or vapour and chemical deposition have proved useful in materials for aircraft power plants, rockets, missiles and nuclear applications."

Jan 1, 1967

By T. A. Rickard

FROM AN OLD MANUSCRIPT THE text for this contribution to the history of the Patio process is a page taken from a Spanish manuscript of Bartholomé Arzaj Sanches y Uela, now in the possession of the library of Brown University (see Figure 1). I owe the photographic print to the courtesy of the librarian. The date, as will be seen, is 1577. The subject is the treatment of silver ores at Potosi, in old Peru, but in modern Bolivia. The group of drawings (see Figure 1) is entitled "Arrangement of the machines in which the ores of silver are ground on the bank of Potosi, the one of two batteries and the other of one". First, top-left, we have the sketch of a "machine of one battery" operated by a water-wheel. From this mill the water runs in part along an aqueduct supported by pillars to the two-battery mill and in part down the hillside, where men are at work with "tubs, which are called cochas, in which are washed the charges of ore and amalgam". Along the top of the page are shown the "various offices in which are stored the copper, the salt, the ucha [llama dung, used for fuel], the lime, and other materials for the re-duction of the ores". To the right of these are "apartments and warehouses in which is stored the ore brought down from the mountain"?the cerro de Potosi. Through the arched portal come the "sheep [llamas] on which is brought down the ore". To this is added a reference to "the second gate, which closes the whole works". On the level above the aqueduct are seen six men carrying skin-bags that contain water. This is being sprinkled on the ore. On the extreme right are six more of these water-carriers. Next comes the two-battery mill. The mortero, or mortar, is marked on the right. Another description says, "Stone, on which the stamps crush the ore, which is called a mortar". To the left of these are indicated "screens of wire in which the ore is sifted after it has been crushed". Farther to the left, near the ore-washers, is a "shed, in which is placed the metallurgist to test the ore of the boxes". Along the left side of the page are sundry buildings, one of which is labelled a "shed in which are placed the cones of silver". Near it, lower, to the right, is the "furnace, in which are roasted the sulphides to facilitate treatment". Farther to the right is the "place where the Indians mix the charges of sulphide ore, which is called a buitron". Alongside is a "buitron in which the charges are prepared for reduction". Inside is a container, to which are attached the words "measure, called topo" On the extreme right is "another buitron in which the Indians mix the ores with their feet, as well as the heaps for the preparation of the reduction". Near the bottom, on the extreme left, is the "chapel where the holy sacri¬fice of the mass is celebrated". Under the first buitron is the "place where they dry the moist ores, called pãpear".

Jan 1, 1935

By F. J. Alcock

THE Magdalen islands have recently been attracting attention as a possible source of manganese. As early as 1880 small masses of manganese oxides were known to occur in the soil and at least one attempt was made to develop them. In 1939, after the outbreak of war, interest in the possibilities of the field was again aroused and during the winter of 1939-40 claims were taken up by two groups of Toronto interests. The islands also contain large quantities of gypsum. During the summer of 1940, the writer mapped the islands geologically, giving particular attention to a study of the manganese occurrences. For a base-map, the chart of the islands was enlarged to a scale of half a mile to an inch. Additional roads were added from traverses carried out in connection with the geological work, and form lines with approximate 100-foot intervals were put on from barometer readings. The geological map is the first that has been prepared of the islands. Previous Work In the summer of 1880, James Richardson of the Geological Survey of Canada studied the rocks of the islands and his r~port concerning them appears as Part G of the Report of Progress, 1879-80. In 1903, J. Obalski, Inspector of Mines for the Department of Lands, Mines and Fisheries of the Province of Quebec, visited the islands, chiefly to investigate the occurrences of manganese and gypsum, and his notes are found in the report on mining operations in the Province for that year. Around 1890, Robert Chalmers of the Geological Survey paid a visit to the islands, and his observations, which chiefly concerned the surface geology, appear in the Annual Report of the Survey, Vol. VII, 1894, Part M, p. 94. The next geological work was carried out by John M. Clarke, Director of the New York State Geological Survey. Clarke paid many visits to Gaspé peninsula between the years 1900 and 1920, collecting fossils and gathering h1s~orical data, and extended his investigations of Gaspé county over to the Magdalens. His Observations on the Magda/en Islands is included in the New York State Museum Bulletin 149, seventh report of the Director, 1910.

Jan 1, 1941

By R. Liu

As Building Information Modeling (BIM) becomes widely adopted by the construction industry, it holds undeveloped possibilities for supporting Facility Management (FM). Some FM information systems on the market claim to address the needs for FM requirement. However, the question of whether the functionalities provided by the current BIM-based FM software companies are those actually required by the FM Professionals still need to be answered. The data is required by FM professionals in the operation and maintenance phases of facilities and type of maintainability problems that frequently occur, which can be solved early in design phase, have not yet been addressed. The aim of this paper is to clarify the frequently occurring maintainability problems and to investigate the potential areas that can use BIM technology to solve the maintenance problems in early the design phase. A survey was conducted to collect perspectives from the industry practitioners for the maintenance problems and their frequency. The survey results indicated that maintainability considerations should be taken into consideration during the facility design phase. The results also address the perceived areas by practitioners that need maintainability consideration in design phase

Aug 1, 2013

By Unknown

We are indebted to the Consolidated Mining and Smelting Company of Canada Limited for the several pictures in this issue showing the progress made in new construction at Tadanac and at Bonnington Falls, B.C. Plate No. 1 shows the down-stream side of the No. 1 hydro-electric station of the West Kootenay Power and Light Co. Limited at Bonnington Falls, on the Kootenay river, at which 17,500 k.v.a. will be developed to meet the requirements of the enlarged zinc and lead refineries at Tadanac. The generators, exciters and switch apparatus were supplied by the Canadian General Electric Company and the step-up transformers by the Canadian Westinghouse Company Limited. The plant throughout was designed, manufactured and erected by Canadians. Plate No. 2 shows the casting room of the new lead-plant and plate No. 3 the new tank-room of the electrolytic lead refinery at Tadanac. These additions will increase the capacity of the lead refinery by some 150 tons daily. The extensions also include practically doubling the zinc plant, and the gold and silver refineries. With the exception of the new stack, all designing construction and installation of the various plants is being done by the Company's own employees at Tadanac. Plate No. 4 shows the progress made in the construction of the new reinforced concrete stack at Tadanac. This stack, of 21 feet inside diameter at the top, will be brick lined and when completed will rise 400 feet above its foundations: the tallest of its kind in the world. The construction is in charge of the Rust Engineering Company of Pittsburgh, Pa. Plate No. 5 is a panorama of the Tadanac smelters and refineries. The photograph was taken from the roof of the lead smelter and gives an excellent idea of the size of the plant and its surroundings. Tadanac produces electrolytic lead, zinc and copper and fine gold and silver. During 1924 the company treated 1,333,523 tons of ore and produced: 161,400,- 769 pounds of lead; 92,197,824 pounds of zinc; l,382,750pounds of copper; 4,074,044 ounces of silver, and 26,976 ounces of gold.

Jan 1, 1925

By John D. Carr

Introduction The Flin Flon zinc plant operates on what is known as the low density or standard sulphate process, that is, the zinc is carried through the plant solution circuit attached to the SO4 or sulphate radical at a concentration not exceeding 175 grams per litre zinc. The process may be described briefly as follows: The zinc is received in the zinc concentrate chemically combined with sulphur and mixed with many other impurities. The concentrate is roasted and most of the sulphur is burned to a gas, which is discharged from the plant. The roasted concentrate, or calcine as it is called, is leached with a weak sulphuric acid solution so that the resulting leach solution contains a high zinc content but a very small proportion of the impurities. The solution is separated from the solids and is purified further by agitation with zinc dust to remove copper, cadmium, and cobalt. This purified zinc sulphate solution is then pumped to the electrolytic department. The solids from the first leach are again leached, but this time with a stronger acid solution to dissolve all of the remaining zinc which is soluble in the strength of acid available. The solids and solution from the leach are then separated. The solids are stock-piled for further treatment at some future date and the solution, carrying a relatively high amount of impurities, is sent to the first leach, where the chemical action is such that the contained impurities are precipitated as solids. The electrolytic department is nothing more than a large number of electroplating cells in which the zinc is plated on aluminium sheets. Since zinc does not plate tightly to aluminium, the zinc plating or sheet is easily stripped from the aluminium and the sheets are collected to be melted and cast into the standard market bars or slabs. In the electro-deposition cells, the zinc sulphate (ZnS04) is split to metallic zinc (Zn) which plates out, and sulphate (S04) which combines with the hydrogen of the water of the solution to form sulphuric acid (H2S04). When one pound of zinc is deposited, about one and one-half pounds of sulphuric acid are formed. This acid is sent to the leaching section, where it dissolves one pound of zinc from the calcine. The solution is purified and is again pumped to the plating cells. The solution travel forms a complete circuit.

Jan 1, 1935

By D. D. Tannant

An experimental and numerical study was conducted on the geomechanical behaviour of oil sands during penetration tests in which a steel wedge with an apex angle of either 20 degrees or 30 degrees was forced into compacted oil sands. The boundary conditions simulated in the laboratory tests are similar to shovel penetration into oil sands. The objective of the laboratory tests was to measure the force required to push a steel wedge into compacted oil sands. A wedge penetration test differs from conventional triaxial tests in that much more shear is generated. The laboratory data was needed to improve calibration of micro-mechanical input parameters for a two-dimensional discrete element model of oil sands constructed with Particle Flow Code (PFC). Initial model calibration was performed with triaxial test data and then a PFC model of the wedge penetration test was constructed. The measured force-displacement behaviour of the steel wedge was compared with PFC modelling results. It was found that different combinations of PFC particle and bond parameters could equally well replicate the laboratory triaxial compression data for bitumen-rich oil sands. When the wedge model was run, it was found that the resulting force required to penetrate the wedge into the oil sands was about four to six times higher than that measured. This clearly indicates that further research is required to improve the predictive capability of PFC models of oil sands.

Jan 1, 2002

1.Assessment of methane content in coal. Given a naturally low methane content in 11 Coal Seam and the fact that the areas of the 11 Seam adjacent to the tunnelway were degassing for a very, very long time due to previous development and mining, it is conservatively estimated that the remaining in -situ methane is less than 0.5m3/tonne. 2. Continuous miner cutting rate based on the past practice. The best loading rate recorded at the past operations of Smoky River Coal was 45 seconds for a 8 tonnes shuttle car. Using these records, the maximum peak loading rate potential at the face is calculated at 0.178 tonnes per one second or 10.67 tonnes per one minute. 3. Methane release at the face. ?The actual face methane liberation, conservatively assumed at 40% of the total in situ content: 0.20 m3/tonne ?The peak cutting rate: 0.178 t/sec ?The maximum (peak) face methane release: 0.20*0.178 = 0.036 m3/sec

May 1, 2003

By Hugh P. Godard, K. Winslow

"AbstractA number of panels of various aluminum alloys in different combinations and secured by steel and three types of aluminum rivets were exposed underground at two locations in a Northern Ontario gold mine for two years and then examined to determine the extent of corrosion. The results indicate Alcan 65S-T to possess considerable advantages over Alcan 178-T, which has been employed in the construction of light skips and cages with considerable success for almost twenty years. Information on the behaviour of these alloys when used with steel rivets and in mixed combinations with themselves was obtained.IntroductionBy the complete substitution of aluminum alloys for steel in the fabrication of mining skips and cages, their weight can be reduced as much as 50 per cent. Lesser savings are possible though its savings are possible through its plates, doors, reinforcing members, etc. Reduced weight leads to economy through increased hoisting efficiency.For a new installation, the basis of design is the rate of production, which thus fixes the live load to be hoisted per trip. A lighter skip permits the use of a lighter rope and a smaller hoist. In deep shafts with high-speed hoists operated in balance, the power required for accelerating is considerable. The hoist size is determined by the weight of skip, load, and rope plus the force required to accelerate or decelerate these three elements A light skip may result in a considerably lighter rope. This is important because, even though the skip can be completely balanced this is not true of the rope. Partial balancing is possible, but conical hoist drums or other devices for this purpose are costly; thus a smaller rope results in a smaller hoist, with consequent general reduction in cost of the whole installation. A reduction in power consumption is also obtained as a result of keeping to a minimum the amount of unbalanced load and the weight of all moving parts which must be accelerated."

Jan 1, 1950

The Beginning ! The status quo simply isn?t sustainable ! Our social license is at risk ! The bar keeps rising ? We must improve our performance, both operational and social ? We must improve stakeholder judgement of our industry by taking action collectively Implementing TSM " TSM Guiding Principles " Performance Indicators " Crisis communications " External Outreach " Tailings management " Energy management " Performance manuals, guides " Reporting " Communities of Interest Advisory Panel

May 1, 2004

By Shen Zhengchang, Dong Ganguo, Chen Dong, Zhang Ming

"It is advantageous to process low grade ores with large scale flotation cells. Large-scale flotation cells have been enhanced with effective volume scale-up. In this paper, the latest and largest flotation cell with effective volume of 680 m3 in China is investigated. The hydrodynamics and flotation kinetics characteristics are conducted using CFD simulation. The similar circulating flow is formed compared to the previous BGRIMM (Beijing General Research Institute of Mining and Metallurgy) flotation cell and it is a suitable fluid dynamics environment. It is demonstrated that the flotation cell produces good gas dispersion and solid suspension. It is indicated that kinetic eddy dissipation plays a key role on collision kernel and collision probability profile. The higher collision probability profile appears at the impeller and stator regions aiding good metallurgical performances. The properties of the large-scale flotation cell are assessed using hydrodynamic numbers. The variation of hydrodynamic numbers such as the power number Np, the Froude number Fr, the air flow number Na, etc with flotation cell volumes show similar properties to previous flotation cells proven to be good in engineering applications. This research would aid structure optimization of the 680 m3 flotation cell.INTRODUCTIONFroth flotation is one of the mains method used in the mineral industry, which is used to process the most of metallic minerals. The proportion of low grade ores has increased with the minerals exploited around world. The increased capacity of concentrators demands large-scale flotation cells. Therefore, flotation equipment has seen a significant increase in size, for which large-scale flotation cells have prominent advantages in improving metallurgical performances, reducing area of plant blueprint printer, lowering the power consumption of the unit ore, decreasing labor cost and overall capital cost. Since the end of 1940’s, flotation cell sizes have continuously increased. To the end of 1990’s, flotation cells with the effective volume of 200 m3 were developed. In the last two decades, flotation cells have achieved a dramatic increase in size. In 2003, an industrial experiment on 257 m3 Smart Cell flotation cells was carried out in Minera Los-Pelambres, Chile. In 2007, the first 300 m3 Tank Cell flotation cell was designed and obtained industrial application in Macraes gold ore, New Zealand. And 320 m3 BGRIMM flotation cells are also in good operation in Toromocho Copper Mine, Peru and Wunugetushan Copper Mine, China. However, flotation cells are conventionally designed using empirically derived relations and geometric similarity. The continual scale-up of flotation cells is still a significant developing process. A 500 m3 Tank Cell was designed for the industrial experiment in Finland and a 620 m3 Tank Cell have also been completed the design. A 660 m3 Super Cell also was manufactured for the industrial experiment released in IMPC 2014. So, the flotation cells with volume exceeding 600 m3 become a pioneering research field for researchers worldwide."

Jan 1, 2016

By Francis Perron

The Directive 019 on mineral industry, which was officially adopted in 1989, is the main tool used by the Quebec Ministry of Environment for the environmental evaluation and control of mineral exploitation projects presented for approval. This document contain the environmental guidelines which must be met by all the mineral companies during and after exploitation. The Directive 019 also contain all the information required by the Quebec Ministry of Environment in order to fully analyse the environmental impacts caused by the mineral projects proposed to the Ministry for approval. The proposed modifications of the Directive 019 cover many new topics that were not addressed in prior editions, these include : water recirculation, groundwater protection, tailings management and post exploitation environmental controls.

Nov 1, 2002

The current mining operations at Newmont Boddington Gold Mine (NBG) commenced in 2008, and commissioning of the processing plant started in the latter half of 2009. Metso Process Technology and Innovation were engaged to assist NBG with commissioning and project ramp-up through the implementation of a comprehensive ?Mine-to-Mill? Process Integration and Optimisation project. This methodology entailed extensive data collection which included drill and blast audits, ore characterisation, comprehensive comminution circuit surveys and review of operational data to assess the limitations within the current mining and processing operations. The results of these investigations have been used to define the operating base line of both the mining and processing areas and identify improvement opportunities. The use of modelling and simulations, utilising actual production data, has allowed for multiple scenarios to be evaluated, minimising the requirement for actual trials and thereby minimising impact on the operation. Improvements implemented to date include: the introduction of routine rock strength measurement for inclusion in block models, modifications to blast design improving ROM fragmentation and downstream comminution process performance, and changes to improve performance of secondary crushing and grinding circuits. Close cooperation between the mine and plant personnel is playing a significant role in overcoming the challenges presented to this operation and further improvements are targeted for the second full year of process plant operation.

Jan 1, 2012

By J M. Fletcher

The responsibility and scope of the Industrial Engineering Department, as organized at the Jeffrey mine, has been broadened to include any study, project or report that could result in more effective use of men, materials and equipment. Although still emphasizing wage incentives and co t reduction, much more varied work is now done, consistent with the in-.creased complexity of industry. Additional activities now include production, maintenance and inventory control improved job evaluation, packaging, labour utilization studies, technical sales liaison, mining, milling and service department n1ethods, plant layout, and specialized project analysis. Additional techniques include the extensive use of work .sampling and standard data. A recent trend has been toward increased emphasis on industrial relations, both in introducing change to the men and in providing requested explanations to Union stewards and officers. These new responsibilities have resulted in the development of specialists in some rather narrow industrial engineering fields, as well as the necessity for industrial engineering assistance in supervisory and job training.

Jan 1, 1963

By R. V. Typliski, G. J. Labarre

"Hudson Bay Mining and Smelting Co., Limited, Flin Flon, Manitoba, Canada, has developed a metallurgical wastewater treatment system employing two-stage lime neutralization, sludge recirculation and conventional mechanical thickening.Laboratory investigations, initiated in 1970, led to the construction of a pilot-scale minewater treatment plant, at Schist Lake Mine, in early 1971. This plant, treating 600 cubic meters/day wastewater containing 30-60 mg/l zinc, demonstrated metal extraction efficiencies of 99% under normal operating conditions.On the basis of this pilot work, a second pilot-scale treatment system was established in 1975 at the Flin Flon metallurgical plant to treat zinc refinery process waste water. Through numerous improvements, including automatic control equipment, the system has evolved to a full-scale operation capable of treating 800 cubic meters/ day wastewater containing 4-11 gm/l zinc. Treated effluent contains 0.2-20 mgll zinc. Hydroxide sludge produced returns to the metallurgical process for recovery of metals while clarified effluent discharges to waste.With the system, Hudson Bay Mining has achieved its original goal: the reduction of environmental contamination, while realizing ii return from metal recovery."

Jan 1, 1980

By A. K. Croteau

"At Craigmont Mines Limited, Merritt, B.C., the mining practice of trackless sub-level caving was started in the latter part of 1966. This type of mining was new to the mine personnel and the mining industry of Canada as a whole. Sub-level caving has presented many old and a number of new problems in maintaining the equipment used in this method. This paper will deal with some of these problems as they affect this particular mining operation. It will be impossible to review all phases of the equipment, but an attempt will be made to cover the most pertinent aspects in maintaining the drilling, mucking and hauling, and auxiliary equipment."

Jan 1, 1970

By M. Nagamori, A. J. Plumpton

"Commercial HCl-leaching of magnesite and serpentine yields highly concentrated aqueous solutions containing 25 mass % to 33 mass % MgCl2. The partial molar enthalpies and heat capacities, the ionic activities of Mg2+ and Cl–, and the Raoultian activity of H2O have been assessed for the concentrated MgCl2-H2O solutions at temperatures of 348 to 373 K. These thermodynamic data are used to calculate the pH of aqueous MgCl2 solutions saturated with a Mg-bearing mineral such as magnesite, serpentine, brucite, forsterite, enstatite or talc. On the basis of these thermodynamic data, technico-economic aspects are discussed as to neutralization with pulverized MgCO3, water evaporation from the MgCl2 solutions, and ore composition including such minor constituents as CaCO3, FeCO3 and Fe3O4. IntroductionA major magnesium electrolytic reduction plant operates in Quebec, where another will begin its production in the year 2000. One uses imported magnesite ore as raw material, while the other will utilize local asbestos tailings (serpentine). Both processes produce a concentrated salt solution of 25 mass % to 33 mass % MgCl2 by leaching the ore with concentrated hydrochloric acid. Thus, the two processes differ mainly in the HCl-leach and related operations. After the HCl-leach of the ore, the serpentine process yields about 25 times more wet cake to filter and wash than the magnesite counterpart. A comparative cost-engineering study with respect to slurry filtration and cake washing has been published elsewhere (Blackburn and Nagamori, 1994). By contrast, the present study considers the thermodynamics and technicoeconomics of the HCl-leach itself for both ores."

Jan 1, 1999

By C. Hilgendorf, J. Gingerich, J. R. Boniwell, M. Drouin, D. David on, J. Boldy

The initial discovery of gold in the Eastmain River area, 310 km northeast of Chibougamau, was made by Placer Development Limited in 1970. This discovery resulted from the drill testing of an airborne E .M. Target located in an area of extensive glacial overburden, within an unexplored Archean greens tone belt considered prospective for base metal deposits. Intermittent exploration by another company between 1973-1977 failed to obtain promising results and the existing claims were allowed to lapse. In 1981, Placer reactivated the project and initiated intensive exploration during the next two years which included aerial E .M. surveys, claim staking, ground E .M. and magnetic surveys, geological mapping, diamond drilling and attendant borehole P,E.M. surveys. Beginning in 1983, exploration has been conducted on a joint venture basis with Eldor Resources Limited, The greenstone belt under investigation has an arcuate distribution pattern relative to a centrally located granitic core. Occurrences of gold mineralization defined to date are located to the south of the granite along a strike length of 7 km, and appear to be restricted to the lowermost of two mafic volcanic cycles. This lower cycle is dominated by basaltic flows with subordinate rhyolitic flows and pyroclas ties. Concordant, variably magnetic, massive to talcose ultramafic units occur towards the stratigraphic top of the lower mafic volcanic cycle and appear to crudely define areas considered prospective for gold on a regional bases. Economic interest in centered on a s tratabound, siliceous, sulphide-bearing unit hosted in a 15- 25 metre thick sequence of rhyolite tuffs, basalts and intercalated ultramafics, The siliceous ore bearing unit ( interpreted as a recrystallized chert) contains from 10%-30% pyrrhotite and pyrite with subordinate chalcopyri te and minor sphaleri te. Alteration is characterized by mica development, silicification and carbonatization. Garnets are also occasionally present in close proximity to the ore horizon. The sequence is south facing, and overturned to the northeast at 35°-55°. Explora tory drilling in the vicinity of two conductive targets has been on 100 metre centres along a 1 km strike length of the prospective sequence. To the end of 1983, two ore zones (A and B) have been partially drill tested with estimated indicated and inferred geological reserves of 1 million tonnes grading 11.7 g/t gold , 14.7 g/t silver and 0.26% copper. The system is open at depth. This discovery is the result of the effective integration of geophysics and geology with contributions by many over a long period of time. Key events that can be emphasized are: ( 1) initial area selection of a remote greenstone belt in 1969 - albeit for base metal deposits , (2) utilization of an airborne E .M. system which successfully targeted the A Zone in 1970 , (3) the timely reactivation of the project in 1981 and the subsequent recognition that the original discovery represented a sulphide bearing stratabound horizon with implicit volcanogenic connotations , (4) the intensive effort in 1982-83 deploying aerial and ground geophysics coupled to volcanogenic concepts of ore distribution which resulted in the discovery of the B and C Zones in 1982, and (5) the integration of downhole P . E.M. surveys and geology to successfully delineate ore at increasing depths . To the end of 1983 , $2.6 million has been expended, and it is hoped that continued effort will result in the eventual delineation of an economically viable ore deposit for the joint venture partners .

Jan 1, 1984

By Biplop Das, E. Herrera, A. Burrows, P. J. Mackey, G. R. F. Alvear Flores

Since the first commercial plant was built at Mount Isa, another twenty ISASMELT™ furnaces have come into commercial operation, and construction of new plants continues. The primary copper ISASMELT™ top submerged lance (TSL) technology continues to attract interest from potential users who seek to smelt productively. In addition to the known benefits of productivity and flexibility, ISASMELT™ operators have also achieved improvements to energy efficiency when switching from their previous technologies. The recent production statistics for operation at Tuticorin, India show that ISASMELT™ has taken the first steps into territory beyond 400,000 t/y (copper cathode basis) and this will likely be the scale chosen by future new copper smelters operating purely on a toll smelting basis. Highly energy-efficient technologies will be expected at these smelters

Jan 1, 2015