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By I. S. Thompson

"The discovery of low-grade copper-silver mineralization near the town of Tipperary, Ireland, by Gortdrum Mines Limited was the result of reconnaissance geological and geochemical exploration followed by target delineation from induced polarization surveys.Initially, orientation studies at the Tynagh lead-zinc orebody showed that such deposits could be readily detected in stream sediments and soils using cold extraction analysis for total heavy metals. Numerous areas showing stratigraphical and structural similarities to Tynagh were then selected for reconnaissance geochemical prospecting.The Gortdrum deposit was detectable through the presence of anomalous metal values in stream sediments 3,000 feet downstream; soil sampling indicated an area of 2,000 by 700 feet containing 2 Yz to 20 times background cold-extractable metal values. Induced polarization surveys defined the dimensions and attitude of mineralization.Drilling to date has outlined (under 10 to 20 feet of till) low-grade copper-silver mineralization within Lower Carboniferous limestones and shales which have been faulted against Devonian sandstone. Mineralization ex-tends from surface to depths of 250 to 450 feet and consists of bornite-chalcocite-tetrahedrite and some chalcopy-rite in altered limestones and intrusive dikes.The deposit is geologically analogons to the Tynagh and Silvermines orebodies, but in contrast exhibits a predom-inant structural control. Provisionally, it is postulated that mid-Carboniferous folding and faulting produced the pre-mineralization high porosity via recrystallization, shearing and brecciation. Subsequently, hydrothermal solutions from the west, with a probable eommon origin to the volcanic dikes, were introduced along the fault planes. Although syngenetic causes cannot be exempted, the field relationships favour an epigenetic origin."

Jan 1, 1967

This paper focuses on the dissolution of various Manganese based compact additions into liquid Magnesium. The experimental procedure employed cylindrical compacts with various Manganese compositions. The various temperatures of the additions and the Magnesium bath were measured simultaneously during the immersion of the additions into Magnesium bath. The exothermicity level of these additions during their dissolution into liquid Magnesium was determined. The relation of the exothermicity level with the dissolution kinetics was also examined. In addition, SEM and EDX work was conducted for additions, which were withdrawn from the Magnesium bath. Finally, the recovery of these additions was estimated by taking samples from the Magnesium bath and conducting ICP analyses.

Jan 1, 2006

By K. T. Aye

An investigation into the leaching of chalcocite and covellite in cyanide solutions at concentrations typically encountered daring gold cyanidation has been conducted. The results indicate that, for both minerals, the extent of leaching is greater under anoxic conditions, but is still incomplete even in the presence of free cyanide ions, with undissolved copper solids remaining in equilibrium with solution species. The speciation of the sulfur and cyanide reaction products in solution are interpreted in terms of the fast formation of a copper(I)- cyanide complexes in solution and a sulfur-rich copper(I) polysulfide solid phase, which then reacts more slowly to produce thiocyanate ions.

Jan 1, 2011

By J. E. Dutrizac

The dissolution of low-iron sphalerite, (Zn,Fe)S containing 0.08% Fe, in ferric sulphate-sulphuric acid media was investigated using closely sized fractions of crushed sphalerite crystals and sintered disks made from the crushed crystals. Linear kinetics are observed, and the predominant reaction products are ZnSO4, FeSO4 and elemental sulphur. The leaching rate increases systematically with increasing temperature, and the calculated apparent activation energy is 56 kJ/mol for the sized sphalerite and 54 kJ/mol for the sintered disks. The relatively high apparent activation energy suggests that the rate is chemically controlled, a conclusion supported by the insensitivity of the rate to the disk rotation speed. The rate increases as the 0.22 power of the Fe(SO4)1.5 concentration, and as the 0.22 power of the H2SO4 concentration. However, in the absence of ferric ions, the rate increases more significantly with increasing H2SO4 concentrations, and relatively rapid rates are observed in solutions containing >0.5 M H2SO4. In 0.1 M Fe(SO4)1.5-0.3 M H2SO4 media, the measured rate decreases with increasing sulphate concentrations, added as Li2SO4. The rate of dissolution of low-iron sphalerite is promoted by dissolved copper concentrations as high as 800 mg/L. In contrast, dissolved silver, even in the 0-2 mg/L concentration range, significantly retards the dissolution of the low-iron sphalerite.

Jan 1, 2008

By O. G. Olvera, D. G. Dixon, E. Asselin, L. S. Quiroz

Dissolution rates of chalcopyrite (CuFeS2) were calculated using electrochemical impedance spectroscopy (EIS). The calculated dissolution rate decreased by a factor of 3.2 after the electrode was passivated. The results presented in this work indicate that the reduction of Fe3+ was the rate-controlling step for fresh CuFeS2 electrodes while the transport of cations within the passive film limited the dissolution rate for the passivated electrode. The transfer of cations at the electrode/electrolyte and passive film/electrolyte interfaces did not affect the dissolution rates of the fresh and passivated CuFeS2 electrodes, respectively. The catalytic effect of pyrite (FeS2) on the dissolution of CuFeS2 continued after the passivating treatment. The contact of fresh and passivated CuFeS2 electrodes with different FeS2 particles resulted in increased dissolution rates, due to an increase in the reduction rate of Fe3+.

Jan 1, 2014

By I. I. Betcherman

INTRODUCTION A DISTILLATION process offers one of the most effective methods of refining metals. Its use is particularly attractive in the case of reactive metals which are not readily treated by pyrometallurgical or electrolytic methods. The 1ow vapour pressure of most metals severely restricts the applicability of the disti1lation process and only one or two metals may be effectively treated under atmospheric pressure at a reasonable temperature. If operations are carried out under reduced pressure several additional metals may be effectively distilled. Table I shows the vapour pressure of a number of metals together with a value of the free energy of formation of their ?oxides. Zinc and cadmium head the list and for many years? they have .been effectively refined by distillation. Sodium, magnesium, and calcium follow in descending order, and they may be distilled readily in vacuo and with difficulty at atmospheric pressure. Sodium, which is not of great metallurgical interest, is not considered. Magnesium has recently been produced in considerable tonnages by distillation methods ( 3). This paper describes the vacuum distillation of magnesium and calcium, their separation from each other, and their separation from less volatile impurities.

Jan 1, 1951

By A. Malfliet, A. Van den Bulck, D. Willems, M. Guo

The feed stock of copper fire refining processes consists of two major constituents: blister copper and high-Cu secondary scrap. A large fraction of this secondary scrap, originating from urban mining, is quite high in impurities such as Fe, Ni, Pb and Sn. Problems arise in electro-refining when these elements exceed certain limits. As a consequence, transformation of the secondary copper raw materials into high grade copper has become troublesome. However, the behavior of impurities relevant to fire refining conditions, essential for anode refineries, has not been studied in detail. Furthermore, limited research has been performed on the distribution of Ni between copper metal and slag. In this study, equilibration at 1300°C of liquid Cu-1wt.% Ni alloy and CaO-CuOx- FeOy-SiO2 slag in vacuum sealed quartz ampoules was performed for 12 hours, followed by water quenching. Electron Probe X-ray Microanalysis was employed to investigate the composition of the equilibrated alloy and slag. The distribution coefficients of Ni between slag and alloy were determined as a function of oxygen partial pressure and CaO concentration. INTRODUCTION Europe’s initiatives for a circular economy, pushing for resource-efficient ways for a sustainable future, puts Europe at the forefront of the globe. In Europe, 50% of the copper originates from recycling, being an excellent example of Europe’s circular economy (Juncker, 2018; Lacasse, 2018). High-grade copper recyclates are made available which regularly contain impurities like Fe, Ni, Sn and Pb. Aurubis Belgium is responsible for recycling these types of recyclates to anodes, cathodes and copper products. However, after fire refining of copper, the aforementioned impurities remain in the anode copper, leading to problems in electrorefining. During the fire refining of copper, a CaO-“Cu2O”-“Fe2O3”-SiO2 slag is used. Fundamental information of the distribution of impurities between the copper and this slag system is therefore essential to understand and improve the copper fire refining process at Aurubis Belgium.

Jan 1, 2019

By M. P. Brameld, R. H. McCorkell

"Overburden covering bedrock uranium deposits was sampled to depths of 29 m and Rn concentrations measured at the same depths. Total-alpha activities, V concentrations and Rn emanation (J) of the samples were measured. The U-flux into the overburden was greater in the past: oxidation and dissolution has since removed most U, leaving decay products which indicate the presence of U deposits when U itself does not. Distributions of U and decay products and their ratios to each other reflect U-migration and degrees of U-removal. Rn distribution in overburden is related to the J of overburden samples and the presence and movement of groundwater. Simple, rapid methods of total-alpha and J measurement are described.IntroductionThe overburden drilling apparatus developed by Bondar-Clegg and Company makes possible sampling and radon measurement in overburden from the surface down to about 50 metres. This apparatus was used here to study the diffusion of uranium and its decay products from ore deposits into over lying overburden at the N deposit of the Amok Ltd. property (Cluff Lake, Saskatchewan) and on the Imperial Minerals Ltd. property at Gooderham, Ontario. These ores are enclosed in bedrock; the overburdens were deposited by glaciers or streams. The migration of uranium and its decay products in such situations and the factors which affect it have been little studied in the past, as readily usable techniques for mapping it in three dimensions have not been available. The results reported here are somewhat sketchy and preliminary, but they indicate the value of the methods used and some of the patterns to be expected. Surface and subsurface sampling and measurements were carried out on 3-line grids crossing known zones of mineralization. The lines were 60 metres apart at Gooderham and 40 metres apart at Cluff Lake."

Jan 1, 1982

By John A. Dresser

At a meeting of the Montreal Branch of this Institute in the autumn of 1928, the Honorable J. E. Perrault, Minister of Mines for Quebec, announced his intention to enlarge the Bureau of Mines of Quebec by the addition of a Division of Geology. The announcement further stated that the geological work proposed should be begun in the following field season, and that it should be on a substantial scale of not less than six field parties. The announcement was received with enthusiasm and much encouragement was held out for the success of the effort. It has been thought that the present meeting would be a suitable occasion to present a report of progress of this Division for the three years that have since elapsed. History This, of course, is not the first geological work to be undertaken by the Bureau of Mines. Prior to the establishment of the Division of Geology, the Bureau of Mines had not been unmindful of the need of geological research, but it had always lacked the means necessary to any sustained work. For more than 25 years the late J. Obalski was the Superintendent and the sole occupant of the Bureau. Yet, even then, Obalski, besides routine visits to mining districts, made a few exploratory trips along the north shore of the St. Lawrence river and one to Chibougamau, but without the equipment necessary to effective results.

Jan 1, 1932

By Harry V. Warren

THE Dolly Varden Mine is situated in the Kitsault River valley, eighteen miles from the head of Alice arm, in the Nass River mining division of British Columbia. During the years 1919-21 it was operated by the Taylor Engineering Company, Limited, and produced 1,300,000 oz. silver from about 36,000 tons of ore. The ore was transported by narrow-gauge railway to Alice arm, and shipped to the smelter at Anyox for treatment. During recent years, a small quantity of high-grade ore has been extracted by leasers and shipped to the smelter at Tacoma, Wash. Unfortunately, the bonanza ores which occurred near the surface did nor persist to depth, and two hundred feet below the exposures only rare and unimportant patches of ridi ore have been found. Two opinions exist as to the origin of this rich silver ore. One, advanced by V. Delmage (1, 2), is that the ores are hypogene, and the other, by G. Hanson(3, 4, S), is that the ores are the result of supergene enrichment. It is true that Dolmage first advanced his view that the ores are primary because they appeared to be analagous to Premier ore, which he had studied in detail and which he considered to be primary. The present authors have had access to excellent suites of material from both mines and consider the comparison well taken, the only essential mineralogical difference being the presence at the Premier mine, in addition to the silver minerals, of gold and electrum. Although the arguments put forward by Delmage have, in the opinion of the authors, never been refuted, nevertheless R. P. D. Graham(6), in a reference to the mine published in 1924, describes the ore as of supergene origin, and since then nobody appears to have challenged this statement. Indeed, in 1935, Hanson re-affirmed his earlier conclusion(5).

Jan 1, 1942

The control of AG mills fed by ores with harder and softer components can be challenging due to the sensitivity of the mill to the ratio of hard to soft components. The mills at LKAB?s iron ore operations are generally well controlled, but there are periods when the throughput falls off dramatically, due to a loss of mill filling. As the ore is upgraded in the sorting plant through magnetic separation prior to milling, this presents an opportunity to manipulate the feed blend in advance. In order to assess this opportunity, a fullscale mill charge was dumped and assayed by size to quantify the build-up of competent waste in the mills. This was supplemented by pilot and locked-cycle laboratory tests at a wide range of feed blends in order to facilitate the development of an appropriate multi-component AG mill model. This paper reports the experimental campaign requirements and methodologies, as well as the major outcomes from analysis and modelling exercises using the industrial, pilot and laboratory multi-component data.

Jan 1, 2012

By Å. Partapuoli, M. Henriksson, P. Wikström, J. Worth, G. Adolfsson

The control of AG mills fed by ores with harder and softer components can be challenging due to the sensitivity of the mill to the ratio of hard to soft components. The mills at LKAB’s iron ore operations are generally well controlled, but there are periods when the throughput falls off dramatically, due to a loss of mill filling. As the ore is upgraded in the sorting plant through magnetic separation prior to milling, this presents an opportunity to manipulate the feed blend in advance. In order to assess this opportunity, a fullscale mill charge was dumped and assayed by size to quantify the build-up of competent waste in the mills. This was supplemented by pilot and locked-cycle laboratory tests at a wide range of feed blends in order to facilitate the development of an appropriate multi-component AG mill model. This paper reports the experimental campaign requirements and methodologies, as well as the major outcomes from analysis and modelling exercises using the industrial, pilot and laboratory multi-component data.

Jan 1, 2012

By W. E. Uren

The Dominion Coal Board was created by Statute passed on July 17th, 1947, and was brought into effect by proclamation on October 21st, 1947. It is, consequently, a comparatively young body, having been in existence for only eighteen months. Before dealing with the constitution and duties of the Board, it may be well to answer the unspoken question of why it has been considered necessary to single out coal as one specific mineral requiring the continuous attention of a specially created permanent Board. In Canada, coal has been the neglected sister of the more spectacular minerals and it comes as a surprise co many to note that in 1948 the value of the coal produced in Canada was higher than that of any other mineral with the one exception of gold. Coal touches upon our daily lives in many different places of which the public are not generally conscious. As household fuel, it is a necessity of life in this northern climate; as a source of steam, it provides the heat for most of our industries; it is the food of the 'iron horse' chat shuttles our persons and our goods across the land; it is the source of power in many parts of the country; it is the chemical reducing agent chat, in our furnaces, transmutes the metallic oxides to the virgin metal. Coal is, in fact, the indispensable mineral chat forms the corner-stone of our present structure of industrial civilization. Is it, then, such an odd thing that the provision of an adequate supply of coal should be a matter of national interest or that measures should have been taken by government co provide for a constant watch, by a permanent Board, on the supply of co al? ? The Board is the result of the recommendations of the Royal Commission on coal which made a long and detailed study of the Canadian coal problem. It is composed of a permanent Chairman and six part-time members, most of whom have had intimate contact with various phases of the industry.

Jan 1, 1949

By C S. Beals

The Dominion Observatory was founded in 1905 and, from the beginning, it work included research in both astronomical and geophysical science. During its first years, up to 1916, the Observatory also included geodetic surveying as part of it scientific program. Although, at the beginning of the century, geophysics did not have the close connection with mineral exploration that it now holds , the founders of the Observatory were men of vision, and they laid a solid foundation for the application of the techniques of geomagnetism, gravity and seismology to an understanding of the Canadian terrain of plain , mountains, seacoasts and shield area . The particular sphere which the Observatory occupies in the field of geophysics has been evolving over a period of many years and it has now a rather definite relation to the work of other government bodies, university science departments and industrial organizations. We have, for example, an over-all responsibility for the regional magnetic mapping of Canada and, as the magnetic field is subject to slow but steady changes, we produce new magnetic maps of the country every five years. These maps indicate the strength and direction of the magnetic field, the variation of the compass and the rate of change of the magnetic elements.

Jan 1, 1963

By Gérald Riverin, Bernard Boily, Daniel Bernard

"The Donalda gold deposit is located in the southern part of the Noranda camp, approximately 2 /em east of the Horne deposit. Combined past production and current reserves total over 1.5 Mt grading 6.9 grams of gold per tonne.The deposit consists of two main veins which are both narrow but persistent structures. The No 1 Vein, hosting about 80% of the gold ore, consists of an EW-striking banded quartz vein dipping on average 25° to the south. Although variable in thickness, it averages lessthan1 metre. TheNo2 Vein, located 300 m below the No 1 Vein, is similar to it except that it dips 50° south. Gold occurs mostly as fine native gold disseminated in quartz, with 2-3% pyrite and trace amounts of various sulphides and tellurides. The wall rocks are only weakly altered and mineralized with pyrite, hematite and sericite.Structurally, the Donalda deposit is centered on the Horne Creek fault (HCF) where the HCF is intersected by the ENE-trending DonaldaandCentralfaults.NorthoftheHCF,theNo1Veinishosted by the Quemont Rhyolite, whereas south of the HCF the vein is hosted by magnetic basalts and diorites of the Wilco Andesite Formation. The No 1 Vein extends across the HCF with only minor displacement, whereas the No 2 Vein has not yet been traced south of the HCF.A preliminary structural analysis of the mine shows that the HCF, which strikes 275° and dips 70° north in the mine area, has a reverse movement a lid that the flat dipping No 1 Vein is a tension vein. Both probably developed in response to the same stress conditions. Although the absolute age of the Donalda veins is not known, structural relationships indicate that they formed during the latest movements of the HCF, but prior to the intrusion of the Proterozoic D' Eldona Diabase. The occurrence along the HCF of gold-rich synvolcanic massive sulphides and much younger vein-type gold deposits (such as Donalda) indicates that the HCF was a very long-lived, deep-seated (?)structure which has controlled the circulation of gold-rich fluids over a long period of time."

Jan 1, 1990

By T. W. Wloder

During recent studies concerning the effects that various surface treatments, surface imperfections, locked-in residual stresses and metallurgical and geometrical notches have upon the mechanical behaviour of metals and, in particular, upon their tension-bending characteristics under impact loads, it became apparent that specially developed methods and samples would be of great assistance in determining the desired data. This paper describes and discusses a number of different types of double-notched tension-bending impact samples which have been considered and examined for this purpose. The types most suitable for exploratory investigations are proposed for application in the study of the _behaviour of metals, their welds, and, in particular, their surfaces, when subjected to various notch-severities, surface imperfections, strain rates, temperatures, and constrained states of stress (i.e. the relations of the three principal stresses). It is expected that the proposed double-notched tension-bending samples and the proposed test methods will also contribute toward further understanding of the cold brittle behaviour and the notch-sensitivities of metals. The possibilities of introducing the so-called impact notch-sensitivity index and relative impact notch sensitivity of metals are discussed. Data obtained on double-

Jan 1, 1961

"In the past year, mining at the Doyon Mine has shifted entirely from open pit to underground. The mine produced 234 692 ounces of gold in 1989 and is expected to produce 225000 ounces in 1990. The Doyon Mill has been running slightly above design capacity, and recovery has increased 3%.IntroductionThe Doyon Mine is located 25 miles east of Rouyn-Noranda, Quebec (Figure I).It is a joint venture owned by Lac Minerals and Cambior, with each holding a 50% interest. Lac Minerals operates the mine under the direction of a management committee.Production at the Doyon Mine began in 1980 with the start up of the Main Zone pit. Shortly thereafter the Doyon Mine became the largest open pit gold producer in Canada.In 1983, a ramp leading to the fourth level and exploration drifts were driven. Results were very encouraging, therefore the decision was made to sink a 2150-foot deep shaft, which was completed in 1986.In mid-1986, production began in the West pit, while underground mining of the West Zone started shortly thereafter, at the end of the same year.In 1987 the mill capacity was increased to 3300 tons per day and the Main Zone underground operations commenced."

Jan 1, 1990

By Jonas Olsson

"The picture of China as an antiquated continent is changing rapidly and fast-forwarding progress is a fact in most infrastructural fields. Mining is not an exception. China is today the largest producer of aluminum, coal, steel, zinc, tin, lead and manganese and the country’s mineral resources comprising approximately 12% of the global reserves ranks them number three in the world after US and Russia.In order to feed the growth industry is needed to take extra ordinary strides to improve supply of raw material and Chinese mines are continuously being upgraded with the latest western technology to meet the increasing domestic demand of base metals.In Anshan located in China’s northeast province Liaoning we find one of the fastest developing mining companies, Angang Iron & Steel Group Co. Ltd. With their six mines that together process approximately 60 M ton iron ore/year Angang Iron & Steel Group Co. Ltd is the largest iron ore company in China. The group’s thorough pre-studies and technical evaluations over the past five years have made them very successful in both plant upgrades of existing operations and green field projects.INTRODUCTIONWe live in a time when the world market is gradually acclimatising to the global consequences of “The China effect”. An effect caused by a formerly sleeping giant nation that during the last years has awakened and developed beyond comparison, primarily because of booming infrastructure projects and demand for capital and consumer goods"

Jan 1, 2006

Mine Safety in Chile ?Since the year 2000 fatality rate averages 34 per year ?1% of world mining labour force but 8% of world?s mining fatalities San Jose Mine Safety ?From 1998 to 2010 eight fatalities ?In 2003 mine inspectors recognized no second means of egress and a raise system was developed ?In 2006 182 workers were injured, 56 of them seriously ?In January 2007, there was a fatality after a rock burst, and the government ordered the mine closed ?Less than a year later the mine was back in operations. It had not complied with some of the basic safety measures ordered. One of those measures was to complete the escape way ladder.

May 1, 2011

By D. P. Goodall

THE development of the oil and gas resources of Western Canada is not, as many suppose, a new industry. For more than half a century an intensive search for these valuable products of nature extended from near the western edge of the Precambrian Shield to the Pacific coast, and from the International boundary north to the Arctic circle. The chief centre of interest to the oil prospector has, however, always lain in that region lying east of the first range of the Rocky mountains and confined largely within the boundaries of the Province of Alberta. Although there are many geological problems yet to be worked out in this Province, the oil-well driller has helped in no small way in determining sub-surface conditions and distribution of rock formations. The chief geological conditions as they affect the drilling of wells are generally re-cognized, and for this purpose the Province may be partitioned into three main divisions: first, the disturbed belt or foothills region extending along the eastern edge of the Rocky mountains; second, the Alberta geosyncline, a broad trough lying to the east of and parallel to the disturbed belt and from which the formations rise eastward to level off and form, third, the plains ? ? region, extending over the rest of the Province. A relatively small area in the northeastern part of the Province is underlain with Precambrian rocks and may be excluded from this classification, as it is of no interest to the oil prospector. The foothills, or disturbed belt, has presented the greatest difficulty to drilling, though it has produced the largest yield of oil within the Province to date. Within the foothills belt, the rock formations consist largely of hard shales interspersed with layers of abrasive sandstones, which wear out drilling bits at an alarming rate. The strata, in most flaces, dip steeply and are cut by numerous thrust faults. Although some o the faults have great displacements, their presence may easily be overlooked or the extent of the fault misinterpreted. Many a prospect well has been located on what appeared to be a suitable geological structure only to find, after drilling through a normal succession of rocks for 4,000 feet or more, that the drill had passed through a major fault plane to a younger formation than that in which drilling was started. Only a repetition of formations already drilled could be expected at greater depths.

Jan 1, 1942