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By Francis A. Thomson

T HE engineer of today is by his training, by his traditions, and by the service which he must render, irrevocably committed to taking his part in public life along with the members of the older professions of ministry, medicine and law. Nevertheless, in comparison with these: three, so long recognized as the "learned professions-all three of which grew out of the functions of the priesthood-engineering in any modern sense of the word is a youthful profession indeed. So youthful is engineering in its present significance, that it may be said to date from the labors of John Smeaton, the lighthouse builder; of Simon Newcomen and James Watt, the inventors of the steam engine; and of George Stephenson, the inventor of the locomotive; at the dawn of the 19th century. Great works of an engineering character had, it is true, been executed long before this, but practically all of them had been rule-of-thumb enterprises, dependent upon a plethora of slave labor for their accomplishment. For illustration it is said that at Rio Tinto in the days of Hiram, king of Tyre, 40,000 men worked for a year to produce three tons of silver from the rich outcrop ore. Such an operation can scarcely be called an engineering enterprise, however, when we remember that a fourth of this number of men in these same mines, from which the richest ore was long ago extracted, produce at present over 100 tons of copper per day.

Jan 1, 1925

This paper aims to address the issue of the public's image of the extractive minerals industry. What is it about the industry that incites such negative feelings and are they justified? Are we really the 'rapists of the land' that many would have us believe? Has the industry really not improved since the old gold boom days?   I believe that the fundamental cause for the public's view is lack of knowledge and understanding of the industry as a result of the dislocation of the end production from its source. There are few people who look at a house, car, record, toilet, tooth-brush, bottle of coke or pair of glasses and see the mine site that supplied the source material. But the mine site and its products should be inseparably linked. This is one area where we should be educating the public û it is all very well being anti-development but the population as a whole is not really prepared to live without its 'mineral'-derived necessities. It is very easy to say that we do not want minerals development in New Zealand but are we prepared to live with the consequences, ie go without its products? We have a duty as a global citizen to develop our own resources rather than expect Third World nations desperate for overseas investment, often with governments who are not prepared to constrain or control their development, to be exploited. New Zealand is not the only 'beautiful' place in the world and we should be aware of the impact that our demands for resources have on the countries who supply us. We have a duty to be a good global citizen.   So how does the industry improve its public image? The key here has to be to educate. This does not have to be high powered or expensive but can be as simple as getting a few local kids' hands dirty panning, and gaining some firsthand knowledge of the industry. The industry also needs to be more pro-active in the public arena. Yes, the industry has skeletons, but the industry should be publicly displaying them û admit that things have gone wrong but let's do it ourselves and not leave it up to the environmental groups to accuse, point the finger and put the industry under public scrutiny. The industry should also be publicising its successes, inviting the local press, councils, etc to view the latest area rehabilitated. But more than anything else we must tell the public what the minerals industry means to New Zealand. Can they really live without us?

Jan 1, 1991

By Liu Xiao, Lin Xiaoying, Ma Geng, Tao Yunqi

"The soft coal in China has several issues, low permeability, high gas content and prone to gas outburst, making it difficult to drill and improve its permeability. Using the rock mass loading test, the relationship of stress-strain-permeability-time of sandstone was investigated. The fracture network that communicates with coal seams to provide the pathways for gas migration can be established by drilling, hydraulic fracturing or loose blasting in the roof and floor about 5m from coal seams top and bottom. The gas migration can be summed up as ""desorption-diffusion-two levels of seepage"" for gas drainage of the quasi-protection-layer in hard coal seams, and ""desorption-two levels of diffusion-seepage"" in soft coal seams. In the quasi-protection-layer, different gas drainage techniques were used during different stages of mining. Gas drainage of the quasi-protection-layers was demonstrated at Hebi Zhongtai Mining Co., Ltd. The results showed that the technique promotes the gas seepage flow, and improves the efficiency of drainage. The influence zone of the quasi-protection-layer was 1601 m2 and the average amount of gas drainage was 328m3/d, with the maximum being 661m3/d. INTRODUCTIONGas is one of the main factors that cause disasters and influence safety production in underground coal mines (SACMS, 2009). The coal-bearing formations in China have been subjected to multiphase tectonic stress field during the period of geological evolution. Coal body was often crushed into fragmented coals and mylonitic coals under the tectonic stresses (Su and Lin, 2009). The gas permeability of coal is generally poor. So in underground, drilling and hydro-fracturing technology have been used to improve the permeability of coal, such as intensive drilling, hydraulic punching, hydraulic cutting, hydraulic extrusion and deep hole blasting. But the gas drainage rate was low, only 23% (Liu, Li, and Li, 2006; Li and Wei, 2006; Henan Polytechnic University, 2008; Ma, et al., 2014; Lin and Wu, 2009; Zhou, et al., 2011) that was much lower than the rates achieved in the main coal-producing countries such as America and Australia whose average rate of gas drainage was 50%. The protection layer mining technology has been used widely as an effective technique to improve the permeability of coal in the mining of multiple coal seams (Cheng and Yu, 2003; Diaz and Gonzalez, 2007; Karacan, et al., 2007; Palchik, 2003; Latham, et al., 2013; Yuan, et al., 2013; Shi and Liu, 2007; Wang, et al., 2008, Guo, et al., 2015; Lu, et al., 2015; Slazak, Obracaj, and Swolkien, 2014 ). In the single low permeability coal seam, there is no protection layer. This kind of coal seam has low permeability, high gas content, soft coal body, and is prone to serious gas outbursts. During drilling, the holes very often spray, collapse, stuck and wedged the drilling tool. The hole length drilled is difficult to reach the required minimum, the service life of holes for gas drainage is short, the construction cost is high, and the holes are difficult to maintain. The gas drainage efficiency of single low permeability coal seam, especially soft coal seams, cannot be improved even though hydro-fracture technology has been implemented, because its permeability is not improved."

Jan 1, 2016

By L. A. Kaufman

"AbstractThe Bureau of Mines, Ottawa, in conjunction with Eldorado Mining and Refining (1944), Limited, has developed an automatic concentrator for uranium ores.A brief review of radioactivity is given which shows the present limitations for obtaining •good results by electronic concentration. The ores after being mined, or at any other stage of a concentrating process, can be analysed for the uranium dissemination and from these results the possibility of an economical concentration can be estimated.The electronic and mechanical parts of the equipment are described. Difficulties in the operation's, and means by which they have •been and are •being overcome, are discussed. The capacity of the units, the results obtained, the man-power required, and other pertinent data are presented. Simple control analysis on the percent U3O8 has been developed.Research is continuing along lines to develop a more completely automatic unit using a scintillation detector, and applying a few new ideas and some devices that have been developed in colour sorting.IntroductionIt is well known how important the Geiger counter is in the field of exploration for uranium. It was in late 1946 that Dr. C. Lapointe, of the Bureau of Mines, Ottawa, first started work on an automatic picking unit to concentrate uranium ores. He used the principle that if a number of pieces of unknown ore, some of which contained uranium, were individually brought up close to a Geiger-Müller tube, then the pieces containing uranium could •be easily picked out due to their activity. Since then a good deal of work has been done by the Bureau of Mines in conjunction with Eldorado Mining and • Refining (1944), Limited, to develop an electronic concentrator."

Jan 1, 1950

By A. F. Ogg

The installed world steel capacity remains 20% above the present world steel demand. Energy costs have risen enormously in recent years, as illustrated in Figures 1 and 2. The role of the sinter plant is becoming more exacting as it becomes vital to minimize energy consumption. Continuous grate sintering, although pioneered in the United States, has always been the second grade burden preparation route, due to the predominance of easily up- graded ores which were more readily agglomerated by pelletizing. To achieve blast furnace performance up to best world standards, sinter of consistent high quality must be produced with virtually no atmospheric pollution. The plants must be capable of achieving this demanding level of quality whilst utilizing high proportions of revert materials, iron ore concentrates and fluxes . However, with the present difficult economic climate in the iron and steel industry, the economic production of sinter and ultimately steel is becoming increasingly important. The iron and steel industry is looking closely at costs and is identifying the need for sinter plants that will cope with a wide range of sintering materials to give the cheapest blend at varying output levels dependent upon demand. In order to meet these requirements, sinter plant builders are designing plants with particular attention on flexibility.

Jan 1, 1980

By M Scamardella

The CSA Mine is located at Cobar, New South Wales, where it was in continuous operation from 1966 to the time it went into receivership on 29 January 1998. When it closed it was under the ownership of Golden Shamrock. Glencore International, in conjunction with Mt Lyell Mining, undertook a due diligence study to determine the feasibility to re-open the mine. This envisaged operating CSA Mine as a low-cost, copper concentrate producer under the direction of Cobar Management Pty Ltd (CMPL). The new workforce would consist of contractor trades people in operating functions under the co-ordination of CMPL staff, both on the surface and underground. This was the key to establishing the new culture in the workforce. The orebodies at CSA Mine are steeply dipping with copper-lead-zinc mineralisation in zones of strong alterations in a fine-grained siltstone host sequence. The predominant economic minerals are chalcopyrite, sphalerite and galena. The major gauge minerals are pyrrhotite, pyrite, chlorite, sericite and quartz. Ore for the project is being developed and mined from two high grade copper lenses within the QTS North system. Chalcopyrite occurs in two forms. The first consists of coarse chalcopyrite grains in association with pyrrhotite or pyrite. The second form consists of chalcopyrite grains intergrown with pyrrhotite grains. This form of chalcopyrite is quite rare. It allows electrochemical interactions between grains, resulting in rapid oxidation of the chalcopyrite surface. Physically this ore looks like, and has been mistaken for æpeacock oreÆ, ie bornite, but is infact oxidised chalcopyrite.

Jan 1, 2000

By D. Campbell Mackenzie

THIS paper is submitted primarily to put on record the results of a number of experiments carried out at the Wingdam mine of Consolidated Gold Alluvials of B.C., Ltd., with the object of establishing a reliable method of concentration of 'wash' and a maximum recovery of gold from the concentrate. It will be generally admitted that, during the last two decades, a tremendous amount of research work has been carried out, both by private companies and Government departments, with a view to improving the technique of the recovery of gold .from quartz veins or lodes. So thorough have been these investigations that milling practice at a modern quartz gold mine is almost an exact science, carried out with meticulous accuracy. In placer mining, on the other hand, very little departure from old traditional methods can be noted, with the exception perhaps of the more modern gold dredges. This may be due to the fact that the concentration of placer gravels, up to a certain point, is comparatively easy. Only a simple equipment of sluice box and riffies seems necessary where the gold is coarse and the gravel free from clay. In the early days of placer mining, when claims were rich and fairly 5hallow, nobody worried very much about fine gold; and, if clay was present, an enlarged dump box was constructed in which the gravel was subjected to a rather desultory puddling. That large quantities of gold are lost in normal placer practice is generally admitted. Some 26 years ago, I had inspectorial charge of many bucket dredges on the Ovens river, in Australia. Occasionally it was necessary for a dredge to work through its own tailing to reach a new section, and almost without exception enough gold was recovered from these tailings to defray the total cost of moving the dredge. Since those days, the technique of gold recovery in dredging has been considerably improved and it is still receiving close attention. Outside of dredge mining, most placer operations, deep or otherwise, are as they were-notorious gold losers, paying little attention to the recovery of fine gold and taking an absurd amount of time over each clean-up. In the Cariboo district of British Columbia, the alluvial gold is usual y associated with varying quantities of black sand (magnetic) and grey sand (non-magnetic); and it can be taken as axiomatic that, if you save all the black sand and grey sand, you save practically all the gold. It is on this hypothesis that we have carried out our research work and brought our recovery system up to its present highly satisfactory standard.

Jan 1, 1937

By Alexander E. McHugh

A study of some variables affecting the recovery of molybdenum from oxidized molybdenum minerals was made. The effects of variations in contact time, temperature, pulp density, particle size, and solvent concentration on the recovery of molybdenum using acid and alkaline solvents were investigated. Chemical analyses, screen analyses and microscopic examinations were made and the presence of important elements determined. A hydrometallurgical method was developed to recover the molybdenum from the oxidized molybdenum ore by simultaneous dissolution of the molybdenum with sulfuric acid, adsorption on activated charcoal and flotation of the charcoal. The molybdenum was extracted from the activated charcoal with sodium hydroxide, precipitated with calcium hydroxide as calcium molybdate and this regenerated sodium hydroxide for additional stripping. A solvent extraction method, using mines, was also studied to recover molybdenum from both alkaline and acid molybdenum solutions. Satisfactory results were obtained.

Jan 1, 1967

By S Maritsa, E K. Chiwandika, S M. Masuka

The iron and steel industry is experiencing an increase in the use of iron and steel commodities within societies, decarbonisation pressures, depletion of high iron ore grades and high energy consumption. This necessitates scrap metal recycling, low-grade ore utilisation using the induction or electric arc furnace to achieve the global target of net zero CO2 emission. The available highquality scrap metal cannot sustain the steel industry but the world has unused hematite-goethite ores. It is the aim of this research that this resource be utilised using the induction furnace to sustain the steel industry in an environmentally friendly manner. Indurated pellets prepared from the hematite-goethite ore, 5 wt per cent limestone and 5 wt per cent coal addition were smelted in the induction furnace at 1350 ± 50°C with 25 mins holding time. The effects of basicity and carbon content were also investigated to optimise the smelting parameters. The results showed that the careful control of the basicity, and iron-to-carbon ratio maximised total metal recovery. The optimal basicity ratio was determined to be 1.3 and a carbon to iron ratio of 1.4 achieved a total metal recovery of 73 per cent. The metal recovery was closely related to the estimated slag melting temperature. The basicity ratio of 1.3 achieved the lowest slag melting temperature estimated to be around 1380°C based on the CaO-SiO2-Al2O3 phase diagram. The recovered metal had a comparable chemical composition and microstructure to that products from an ITmk3 furnace.

Jun 19, 2024

By Zuoren Huang

The flowsheet of the hyd.rametallurgical zinc plant which is in use at Zhuzhou Smelters is described. The principal features of the process are fluid bed roasting, continuous calcine leaching, solution purification, zinc electrolysis, electrolyte cooling, and finally, the melting and casting of zinc forms. The Zhuzhou process for the flotation of silver from the leach residue collected on the Moor filters is described. The technical details of the process are outlined and the operating data are analyzed. The flotation facilities are described in detail and concentrate grades and recoveries are presented. The waelz process is used to concentrate In, Ge and Ga remaining in the leach residue after silver flotation. These elements subsequently are recovered by selective leaching in sulphuric acid, and details of this operation also are presented.

Jan 1, 1990

By Dezhou Wei, Cong Han, Shuling Gao, Wengang Liu, Yanbai Shen

The recycling schemes of copper mineral to a copper raw ore produced in China is investigated in this paper, of which is aimed at copper concentrate‘s grade is over 26.00% and recovery is over 90.00%. The primary copper mineral the raw ore is chalcopyrite and the main gangue minerals are quartz, orthoclase, albite, clinochlore and phlogopite. There are four useful metal elements contained in the copper raw ore, which are Cu, Pb, Zn, Au and Ag, and the grade of each is 3.75%, 0.01%, 0.11%, 0.31 and 483.5 g/t. Two floating recycling schemes and its corresponding flotation reagent system were determined. The results show that calcium oxide, sodium carbonate and sodium sulphide were used as regulators, sodium n-butylxanthate was used as collector and terpenic oil was used as frother in two floating recycling schemes are effective. The open-circuit test’s results show that the copper mineral contained in raw ore can be effective collected, and both concentrates gotten through two schemes are up to grade.

Jan 1, 2014

By J. M. Newell, G. R. Peatfield

"The Red-Chris porphyry Cu-Au deposit is located between Ealue and Kluea lakes, southeast of the village of Iskut on the Stewart Cassiar highway in northwestern British Columbia. It was explored by Texasgulf Inc., in a joint venture with Great Plains Development Company of Canada, Ltd. and Silver Standard Mines Ltd., during the period 1973 to 1980. Exploration resumed in 1994, following acquisition of the interests originally held by Texasgulf and Great Plains Development by American Bullion Minerals Ltd.Prospectors were first drawn to the area by prominent limonitic stain zones exposed in creek gullies in the western part of the property. These zones are developed on the alteration halo at the western periphery of the deposit. The potential ore zones do not crop out and were first exposed in a bulldozer trench excavated in 1971. Subsequent exploration was by percussion and diamond drilling, guided to some extent by induced polarization surveys. In 1976, estimated resources contained within two crudely designed open pits were 41 million tonnes with an average grade of 0.56% Cu and 0.34 g/t Au, with a cutoff grade of0.25% Cu. New resource estimates based on a major drilling program completed by American Bullion in 1994 were released as this paper goes to press. These estimates were calculated using various copper cutoff grades; at the 0.4% Cu cutoff, the ""in-situ geological reserve"" is given as 100 million tonnes grading 0.58% Cu and 0.46 g! t Au (American Bullion Minerals Ltd., 1995).The deposit consists mainly of pyrite, chalcopyrite and increasing bornite at depth, in zones of quartz-vein stockwork hosted by an elongate body of altered monzonite porphyry of latest Triassic or earliest Jurassic age. The stock intruded volcanic and sedimentary rocks of probable Stuhini Group affinity and is in faulted contact with sedimentary rocks of the Jurassic Bowser Lake Group. Gypsum stockworks are developed in the higher levels of the subvolcanic porphyry system. Late-stage quartz-carbonate veins carry small amounts of galena and sphalerite. Complex faulting within the deposit makes drill-hole correlations difficult. Alteration assemblages include an early potassic phase, almost completely destroyed by later phyllic alteration, and surrounded by a propylitic assemblage dominated by ankeritic carbonates in altered sedimentary rocks.The deposit has characteristics of bath the alkalic and calc-alkalic classes of porphyry copper deposits. The development of quartzvein stockwork suggests a calc-alkalic affinity, but the hostrocks contain little or no free quartz, molybdenum is present in trace amounts only and gold values are significant. Copper grades vary between wide extremes with unusually high grades in some sections of the deposit. The weight of evidence available in the 1970s led us to place the Red-Chris deposit firmly in the alkalic family. The quartz-sericite alteration assemblage was attributed to breakdown of potassium feldspar in a near-surface alteration environment in which seawater may have had a significant role. These interpretalions are retained here, but preliminary conclusions from the most recent work suggest that they may require some modification."

Jan 1, 1995

By F. J. Bruey

Refdist is a simple but valid approach to planning or analyzing a test-vs-control plant trial that uses accumulated plant performance data to calculate objective criteria for judging the trial outcome. Refdist calculations and results are explained and illustrated with data typical of the mining industry. Findings from a simulation study of Refdist statistical properties are reported. Suggestions for dealing with messy data situations are offered.

Jan 1, 1999

By Brian J. Gorva

The key objective of forming a cartel is to increase profits to members of the cartel by taking the following action: a) control output; and b) control price. However, while attempting to obtain monopoly profits the cartel members have to contend with costs associated with cartelization and such costs include the following: political costs; the cost of coordinating output and price; organizational costs (such as cheating); and administrative costs (such as the cost of attending cartel meetings). The objective of commodity exchanges is to provide an open, free market where buyers and sellers may openly complete transactions and pricing information can be immediately disseminated. These transactions include the following: a) to provide facilities for "hedging", or transferring price risk from buyers and sellers of physical commodities to "speculators" through the medium of buying and selling futures contracts, and b) taking physical delivery of metal on due dates.

Jan 1, 1983

By D. Hatfield, G. de Jager

"The rapid developments in computer vision and computational resources are creating new possibilities for the use of machine vision systems for industrial control. A number of commercial image analysis systems exist, and research into improved measurements of froth performance is ongoing. An integral part of the implementation of these systems is the validation of the relationship between image analysis measurements and flotation cell performance. This paper discusses the factors affecting concentrate flow and presents the results obtained from one such system with respect to its ability to estimate the flow of concentrate from a flotation cell.The relationship between froth flow speed and the rate of recovery of concentrate from a flotation cell was investigated on two industrial operations, both processing PGM (Platinum Group Metal) bearing ores. Results are presented that show a relationship between froth flow speed and concentrate yield."

Jan 1, 2003

By T. A. Rickard

An educated man is distinguished neither by his clothes nor by his knowledge; he is replarkable not for the things he says, but for the way he says them. You cannot even stand with him under an archway in the rain without finding him out. He may talk only of the weather. His words and his phrases alike may be simple. -at distinguishes him is the arrange- ment of his words; however desultory his talk, it will be method- ical; he has habituated himself to foreseeing the part to be played by each word he uses and the place to be taken by each sentence he utters. On the other hand, the uneducated man, though shrewd and well-informed, will relate facts and events as they recur to him, generally in disorder; in his effort to recollect and in his attempt to rectify forgetfulness he will pause irregularly, filling the intervals with meaningless phrases, such as "and then ", "and: so ", or 'said he to me", "said I to him"; and even the contipuous parts of his story will be told confusedly-because he has not learned the proper use of words.* My own experience as an editor of technical manuscripts has taught me that the misuse of 'that' and 'which' is a fruitful cause of obscurity and confusion. The relative pronouns have distinct functions, and no writer can express himself clearly until he has learned to discriminate between these I functions. For example:

Jan 1, 1931

By J. A. H. Church

The report is too voluminous to be considered in detail within the scope of a single paper, so I will confine my consideration of it to the broader aspects, leaving other members to deal with points of particular interest. The method of presentation leaves one with an uneasy sense of prolixity and confusion of thought; the foreword by the Chairman may well be accepted as a true index of the whole. His argument amounts to this: Recognizing at the outset the futility of divided counsels, it was deemed advisable to arrive at unanimity. To this end, some members subscribed to views to which they do not whole-heartedly assent, thus giving weight to conclusions with which they were at variance. Unanimity cannot be qualified-either it exists or is absent-and, moreover, in the text of the Com-mission I can find no word that unanimity is required. Surely it would have been preferable to have a unanimous report covering such aspects as were acceptable to all members, with minority reports by individual members on such other aspects as were controversial, leaving it to the Government to give such weight to the divergent views as the personality of their sponsors might warrant. In the final analysis the value of an opinion varies directly as the personality of its exponent.

Jan 1, 1926

By Xu Lin Sheng

During the mining course, when the roof above coal seams is constituted by thick and hard sandstone (conglomerate), sudden roof movements often take place with great force and de¬struction which is the biggest danger to the safety and production. Such sever movements of the roof in mining directly relate to the rock mechanical properties which are the main fac¬tors that influences the regularity of hard roof movement and its destruction form. A significient work and important technical way for applying rock mechanics into mining en¬gineering is studying the rock mechanics of the hard roof and altering some of the rock me¬chanic parameters which induce the improvement of the rock properties in order to efficiently control the movement of the hard roof.

Jan 1, 1989

By C. R. Tang

The respirable dust real-time monitoring equipment export information is complex, and electromagnetic wave wireless transmission is affected largely under mine conditions. The respirable dust concentration information transmission method based on led light equipment is proposed. The respirable dust concentration data of the individual real-time monitoring equipment is encoded to fit the system transmission; the encoded signal is modulated onto the LED mine lamp; the light signal is transmitted by the spatial channel; the signal is received by the receiver to the photoelectric conversion to restore the respirable dust concentration data for subsequent processing. Simulation and verification experiments showed that the respirable dust concentration information transmission method based on led light equipment can achieve the LED miners? lamps visible light wireless data transmission.

Aug 1, 2013

By Paul Gottlieb

This paper reviews the status of automated applied mineralogy today and describes the history and fundamental theoretical and practical bases underpinning the development of automated systems. Details are given of the technical challenges that were faced in creating the new technology and in applying it to a range of applications. In recent years, automated mineralogy has become established as an essential enabling technology for the reliable acquisition of statistically sound comprehensive mineralogical and metallurgical data. This has had a revolutionary effect on the industrial use of such data in the study of geology, mining and mineral processing. Previously, using manual methods, it was not feasible to attempt this work because the large data sets required could not be assembled in a realistic timescale. There was a reliance on individual expert mineralogists and this was not scalable. The speed, reliability, detail and repeatability of the modern automated measurements has now made this type of analysis routine. Automated Applied Mineralogy has come of age! More than 100 systems have been installed around the World. Automated mineralogical analysers such as QEMSCAN® were originally developed as diagnostic metallurgical tools to improve mineral processing plants using samples drawn from plant surveys, bench and pilot-scale tests. They were used mainly for the assessment and auditing of size fractions of mill products, such as concentrates and tails. Subsequently, they began to be used for concentrator design and optimisation where ore characterisation was used to help understand the relationship between the feed ore and its subsequent behaviour in the plant. They are now widely used to measure exploration cores and drill chips from drilling programs to predict eventual metallurgical performance. Ore samples can be classified into metallurgical, as well as geological types, by combining mineralogical features in the ores with metallurgical properties related to grade control, separation, comminution, flotation and leaching behaviour. Three-dimensional block models of ore deposits are now being created based on processing response in addition to geological and mining properties. The development of automated systems began in Australia, the United Kingdom and Canada in the late 1970s and early 1980s. There were many technical challenges. Mathematical theories of randomness, sampling theory, image analysis and stereology were developed to ensure sample representivity so that meaningful information could be obtained. Sample preparation, presentation and measurement methods were developed to ensure that the random sampling was preserved during the measurements. Methods of automatic measurement and mineral identification evolved from the use of electron microscopes, fitted with backscattered electron brightness and energy dispersive X-ray detectors. Operational procedures were required to ensure that these instruments could accommodate a large number of samples and operate unattended for long periods of time. The new technology was progressively applied to a range of commodities and applications and new analysis methods, such as liberation measurement, were needed for metallurgical interpretation of mineralogical data.

Jan 1, 2014