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By P. C. Benedict

Introduction and Summary The Northern Empire mine is a mile east of Beardmore, and 100 miles northeast of Port Arthur, district of Thunder Bay, Ontario. Production started in March, 1934, and terminated in September, 1941. During this period, the mill treated 425,866 tons of ore, from which 153,103 ounces of gold were recovered. The lowest level from which ore was mined was the 1900, but considerable drifting was performed on the 2075 level and 800 feet on the 2415, the deepest level. The following description of the geology of the mine is recorded by the senior author but is based on the observations and complementary mapping of both authors. The vein strikes about N.72°E. and has an average dip of 80°S. (Figure 1). In stoped sections, the quartz averaged about two feet wide. On the 1725 level it was drifted on continuously for more than 7,000 feet, but in the mine as a whole practically no commercial ore was found beyond points 1,400 feet west and 1,800 feet east of the shaft. Conspicuous wall-rock alteration extended throughout this section but not much beyond its limits. There was some splitting of the vein and widening of the alteration halo on the lower levels. The average general colour of the quartz changes with depth. It may be generalized, from top to bottom, as light grey to dark grey to brownish. The brownish quartz first appeared near the bottom of the ore.

Jan 1, 1947

By Malcolm Black

Introduction Before beginning to write this paper, I decided that I should first find suitable definitions of the words Sample and Sampling. The dictionary gives: "Sample.-A portion indicative of the whole"; and according to Baillie (1), sampling is "That process whereby a representative and comparatively small portion of material is selected from a large bulk, and preserved under such conditions as shall prevent contamination or avoidable alteration, with a view to the formation of valid conclusions regarding the suitability of the bulk for specified purposes". These comprehensive definitions are alike in substance, and indicate that unless a truly representative portion is taken, it is not a sample. Ore 'as mined' generally varies a good deal in composition, and, in crushing, segregation takes place. Some of the minerals present, due to differences in hardness and friability, break into smaller pieces than others, and, on reaching the bin, the coarse particles roll away, leaving the fines behind. The result of this segregation is generally quite noticeable on the conveyor feeding the mill, especially when the bin is nearly empty and the crushing plant shut down. Should the sampling period synchronize with either the coarse or the fines, the sample obviously would not be representative. I agree that this is rather far fetched, but I maintain that such a condition is possible. Assuming that a representative sample may be procured from the feed conveyor, the method of cutting it down for assay has considerable influence in maintaining the original condition of the sample. The finer the material is ground after each cut, the more uniform the sample will remain. To illustrate this point, let us take a quantity of fine sand and add, say, three grains of rice to represent metallic particles. We may mix this sample by any of the known methods, then cut it into four equal portions. It is obvious that at least one of the portions will be without a rice grain. But let us grind the three grains of rice into flour and proceed as before. Now there will be a much greater chance of including some of the rice in each portion.

Jan 1, 1935

By Z. Manafi

Bioleaching of a copper sulfide ore containing "activated pyrite", using a mixed culture of mesophilic bacteria, was studied. This type of copper ore had been found unsuitable for flotation because it produces a concentrate containing relatively high iron concentrations and, therefore, a low copper grade. Microscopic observations showed that pyrite particles had been activated by the formation of a thin film of chalcocite. Hence, a bioleaching process was considered as an alternative to treat this ore. Following shake flask and acid consumption tests, column tests of the crushed ore (75% -12.5 mm) were initiated and the effects of culture medium, agglomeration, and irrigation type on copper recovery were studied. The results showed that all the columns containing bacteria had copper recoveries around 90% compared to the abiotic control column with a recovery of 50%. It was concluded that bioleaching could be successfully utilized to process copper ores containing activated pyrite.

Jan 1, 2007

By E. Thune, F. Stålesen, E. O. Stensholt, O. M. Dotterud, E. E. Henriksen, P. O. Ramsdal

"The development and commercial operation of the Falconbridge chlorine leach process have been described in papers in 1985 and 1987. Since this time, various process improvements have been implemented and the capacity of the Kristiansand refinery has been increased to 85 000 t/y Ni, 40 0000 t/y Cu and 4500 t/y Co. The focus has been on continuous improvements in productivity, the use of energy and other costs. Several environmental issues have also been eliminated or reduced since 1987. IntroductionThe first nickel refining operation in Kristiansand, Norway, started in 1910 based upon raw materials from Norwegian mines. In 1929, Falconbridge Nickel mines purchased the refinery to acquire information and the patent rights to the Hybinette refining process that was practised at the small Kristiansand refinery. Falconbridge ownership has now, for more than 70 years, provided a strong base regarding raw material supply, financial resources and technical support for further expansions and major technical improvements at the refinery.The main concepts of the new chlorine leach process were developed in the laboratories from 1966 to 1969 and the process was piloted from 1970 to 1972. The main stages in the commercial plant were started in the 1975 to 1981 period. After 1981, there have been a number of process modifications, plant expansions and improvements to operating practices. The developments up to 1988 have been described in previous publications (Stensholt et al., 1986, 1988).This paper presents an overview of the process and how it is practised at Falconbridge Nikkelverk AS (FNA) today and describes some of the main changes that have been implemented since 1988. During this time, the nickel capacity has been expanded from 54 000 t/y to 85 000 t/y and the cobalt capacity from 2000 t/y to 4500 t/y. The paper describes how these expansions were achieved together with continuous improvements in operating efficiency and also gives an overview of the main environmental concerns at the refinery."

Jan 1, 2001

By Stuart J. Schofield

Introduction The study of the ore deposits of British Columbia is one of fascinating interest not only from a scientific but also from a commercial standpoint and certain wide problems in connection therewith have interested me for some years. Several of these problems have been set forth in papers presented before this Institute on previous occasions. In 1918 it was pointed out that the commercial ore deposits of British Columbia, with one exception, were associated with the granodiorite batholiths of upper Jurassic age. This was followed, in 1922, by a discussion of the ore deposits of British Columbia in which the mineral belts of the province were defined and named, showing a zonal arrangement of ores in which the Pacific coast deposits are characterized by the presence of copper, while the interior belt is marked by the presence of silver, lead, and gold. Methods Of Investigation In reading various reports on the economic geology of British Columbia one is struck with the fact that the mineral veins may be arranged as a system and further examination will show that such a system follows two main directions, one northeasterly and the other northwesterly, both related in origin to the same force.

Jan 1, 1925

By R. Clarkson

"Free gold particles occur in many base metal and precious metal mines throughout the world. Due to the high density and malleability of gold, large circulating loads of free gold particles can build up over time in grinding circuits. This gold is often deposited in unintended traps throughout the mineral processing system.These unidentified free gold deposits represent a serious security risk as well as an inaccessible inventory of gold. Deposits of free gold particles often remain undetected by mine management until they are accidentally discovered while repairing mill equipment.Nuclear tracers have been used to determine the free gold recovery efficiency of gravity recovery equipment, drills, and sampling equipment (Clarkson, 1994, 1995; Walsh and Rao, 1986; Walsh and Kelly, 1992). In November, 1993, the author inspected the grinding circuit at La Mine Doyon in Rouyn-Noranda, Quebec and made recommendations to recover coarse gold and to eliminate gold traps from the circuit. In 1995, the author salted mineral processing circuits with radioactive gold particles. The gamma and X-ray radiation from gold’s nuclear isotope (Au198) were detected through steel, in pipes, and in moving equipment using scintillometers. The radiotracers proved to be a safe, rapid and accurate method of identifying gold traps and improving security.Nuclear TracersWhen particles of gold are placed in a nuclear reactor, some of the gold atoms (Au197) absorb another neutron in their nucleus to form gold’s radioactive isotope (Au198). In the process of radioactive decay, this isotope emits high energy gamma rays and X-rays which are easily detected (even through steel) with scintillometers.Radioactive gold (Au198) has a very short halflife of 2.7 days. At the relatively low activity levels used for tracing, the particles remain detectable with a small hand-held scintillometer for about 10 to 14 days. After 14 days the irradiated gold is close to background levels and within two months it is essentially non-radioactive. The radiation has no effect on the recovery characteristics of the gold particles. The gold radiotracers are very safe due to their very low level of radiation, short half-life, and their inherent physical and chemical stability. However, the use and possession of even mildly irradiated gold is strictly licensed and regulated."

Jan 1, 1997

By H. Clare Horwood

"In the Red Lake area in northwestern Ontario the relationships between general structures and structures containing ore deposits are among the most unusual and most interesting of any in the Precambrian Shield. The more important orebodies, which are in the central-eastern part of the area, occur in a variety of rocks on the northeastern, eastern, or southeastern sides of a series of granite stocks. Other deposits in the western part of the camp also are structurally associated with granite masses .The relationships were determined in the course of general and detailed geological mapping by detailed analyses of the fracture patterns in the rocks adjacent to the orebodies. In every case it was found that the structures containing the ore were produced by compressive stresses from the direction of intrusion of the granite masses( 2).The Red Lake area lies in the Patricia part of the district of Kenora and is accessible by boat from Hudson or by airplane from Kenora, Sioux Lookout, or Winnipeg. A road from Vermilion lake, on highway No. 17, was opened in August, 1947.The first discoveries of mineralization in the area that proved to be of economic importance were made in 1925 by Lorne Howey and George McNeely for Haileybury interests and by Ray Howey and W. F. Morgan for Mcintyre-Porcupine Mines, Limited. Both prospecting ventures were organized because of information presented by Bruce(l) in his map and report for the Ontario Department of Mines. The discoveries, which were both along the same structure, a quartz porphyry dyke, later developed into the Howey and Hasaga gold mines. Other discoveries were made at intervals as a result of prospecting and development work on ground staked for its location."

Jan 1, 1954

By N. R. Thornton

This paper discusses the rapid growth in the application of instrumentation for metallurgical process control. It covers such methods as ultrasonics, pulp density measurements, on-stream X-ray analysis and reagent control, as well as the expanding use of computer control and data acquisition.

Jan 1, 1971

By D. M. Xue, T. B. Li

"With the increase of human engineering activities, global climate change and active plate tectonics movement, the giant landslide frequently occurred in southwest China, which caused huge property and human losses. Besides, the potential landslides pose severely threaten to the construction and operation of airports, railways, highways and power stations etc. In order to provide accurate guidance for the landslide investigation, stability analysis and mitigation, the giant landslide is redefined according to landslide volume, depth of slip surface, complexity of landslide mechanisms, and degree of landslide mitigation difficulty, and classified with the typological classification approach based on the twofold attributes of landslide behavior including formation mechanisms and reactivation features. Finally, the threefold particularity of the giant landslide is also summarized, which enables a more effective landslide mitigation design.INTRODUCTIONWith the increase of anthropogenic activities, global climate change and active plate tectonics movement such as continual uplifting of Qinghai-Tibet plateau and strong earthquakes, the occurrence of giant landslides was in ascending trend in southwest China (Huang, 2009), which caused serious destruction, and greatly endangers such engineering construction from safety, time and economic aspects as airports, railways, highways, power stations, etc. Giant landslides have huge scale, complex formation/reactivation mechanisms and mechanical behavior. They may not be identified during the hazard investigation, but may be firstly initiated or reactivated due to the following engineering activities, heavy rainfall or strong earthquakes. Consequently, the landslide mitigation is inevitable and costly. However, it is difficult to control the deformation of giant landslide with lack of a correct understanding of genetic mechanisms (Marui, 2012; Zhang, 2000) and the excessive large sliding forces of the slide blocks calculated by the conventional limit equilibrium method. For instance, the failure of anchored pile wall for the No.102 giant ancient landslide (Zhu et al., 2012) and stabilization measures for the Sidi Rached viaduct landslide(Guemache et al., 2011); four rows of piles had not prevented the occurrence of the No.12 landslide in a high fill slope in the Panzhihua airport (Li et al., 2012)."

Jan 1, 2015

By N. D. Wineinger, J. Jodouin

"An Independent Electricity System Operator Industrial Accelerator Program (IESO IAP) case study was completed for a mine in Ontario, Canada by SRK Consulting, Inc. The purpose of the study was to analyze the ventilation system to determine whether and which system improvements could reduce the overall electrical power demand of the mine. Financial incentives are offered by the IESO IAP grant program to help cover the capital costs of these improvements. This study included the completion of a full mine ventilation survey as well as measurement of a full suite of electrical parameters of the surface and underground ventilation fans. After these measurements, a base ventilation model was created and established as the system baseline. Changes to the ventilation system were modeled, and their effects on the power demand were projected. The results of the study showed that several improvements were possible which may significantly improve the efficiency of the ventilation system and reduce mine electricity demand.INTRODUCTIONIn 2017, a ventilation study was conducted in accordance with the Independent Electricity System Operator Industrial Accelerator Program (IESO IAP) at a mine in Ontario, Canada. The IESO IAP is designed to assist eligible transmission-connected Canadian companies operating in Ontario to fast track capital investment in major energy conservation projects. The program will provide financial incentives to encourage investment in innovative process changes and equipment retrofits to reduce electricity consumption on the provincial system and to help companies become more competitive by positively impacting their bottom line. There are now four initiatives under the Industrial Accelerator Program:1. Retrofit2. Process & Systems, including Small Capital Projects3. High Performance New Construction4. Energy Managers – a new initiative under the Industrial Accelerator ProgramWithin the program, companies may propose energy saving changes to their current systems where applicable and appropriate. Companies may then be awarded funding to implement the proposed changes. The program allows partial financial compensation to implement certain energy saving changes that would otherwise not be considered due to high capital costs. For larger projects, such as underground mine ventilation systems, a detailed engineering study must be submitted. This study must detail each energy saving change or measure, its savings, and calculate the financial incentives using the IESO IAP Payment Structure. The payment structure for a project is an amount equal to the lowest of the following (Independent Electricity System Operator, 2015):"

Jan 1, 2019

By A. Bhowmik

Uranium Refining is the process in which undesirable neutron absorbing elements such as Boron (B), Gadolinium (Gd), Cadmium (Cd), Europium (Eu), Samarium (Sm) and other heavy metals (Fe, Ni, Co, Ca, Mg etc.) are removed to make it nuclear pure. At present, Uranium refining is carried out by solvent extraction process by using organic based solvent e, g. TBP diluted with Kerosene. The above process generates lot of nitrate bearing liquid waste and degraded organic. In order to eliminate use of hazardous organic and ammonia for Uranium refining altogether, a new process has been developed. In the new process, Yellow Cake is dissolved in nitric acid and uranium peroxide hydrate is precipitated selectively from the solution leaving all the impurities in the solution by using commercial grade hydrogen peroxide at a pre-defined pH, U conc., temperature and stoichiometric quantity of hydrogen peroxide under mild agitation. The precipitate is filtered and washed with DM water to obtain nuclear pure product meeting purity standard as per ASTM C ? 753-99.The product is spray dried and calcined to obtain uranium oxide. The process eliminates use of organic, flammable, toxic chemicals, consumes less quantity of nitric acid and uses environfriendly chemical hydrogen peroxide. The process is simple and can be integrated in the mill. A patent application is entering national phase in several countries including CANADA and abstract/full paper is available in WIPO publication no: WO/2009/013759.

Aug 1, 2010

By J. Chretien

The ability to continuously monitor the air quality within a mine has become instrumental in becoming a low cost producer. The many considerations involved in monitoring air quality include sensor type, hardware placement, as well as data storage medium. BESTECH has had the opportunity to gain insight into these air quality monitoring considerations through deployments of NRG1-ECOTM, a minewide energy consumption optimization system. This paper explores the particular challenges overcome through these installations, and provides a set of guidelines for mines that want to maximize data capture while minimizing costs. It provides a view of additional benefits of air quality monitoring, such as ventilation control, reporting and trending.

Aug 1, 2013

By C. Feng, D. W. M. Arrigan

Arsenic is often associated with gold mining operations and poses a significant health and environmental hazard. While a number of technologies are available for removing arsenic, none of them is effective under all conditions. Although adsorption is a promising approach, most methods focus on the purification of water under neutral or acidic conditions and tend to be less effective in gold mining process waters, operating under alkaline conditions. In this study, the removal of As (III) and As (V) from both arsenic-only solutions and simulated process waters using composite magnetic nanoparticles was investigated. The nanoparticles consisted of magnetite (Fe3O4) or maghemite (?-Fe2O3) cores covered by various metal oxides with Langmuir adsorption capacities of As (III) and As (V) ranging from 31.4 to 79.1 mg/g and 10.2 to 25.5 mg/g, respectively, in arsenic-only solutions at pH 9. Their adsorption capacities were further recognised by the adsorption tests conducted in simulated process waters. The ability to remove As (III) is of particular importance as it is harder to remove it from alkaline solutions. The magnetic cores allow simple and efficient magnetic recovery of the As-loaded nanoparticles.

Jan 1, 2017

By W. M. Tupper

Municipal governments recognize the importance of aggregates in the local economy and the need to manage this resource in the interest of the public good. They have encountered problems with regulating the industry and the dichotomy between the urban need and the rural source. They have suffered from a lack of financial benefit, an adequate aggregate inventory, provincial strategy, economic information and public understanding. A provincial strategy for ensuring the availability of aggregate supplies to developing areas of the Province is essential. The Province should also be responsible for licensing, research, technical expertise on rehabilitation, public education and financial assistance. Upper-tier municipalities (regions or counties) should assume responsibility for resource management, including resource availability, demand characteristics, truck routing, phasing of resource development and sequential land-use planning. Area municipalities (towns and townships) can best determine the social and environmental impact of a specific aggregate development proposal and should therefore have the primary responsibility for the location of new pits and quarries. They should also have the authority to supplement provincial regulations concerning operating standards and the phasing and standards of site rehabilitation.

Jan 1, 1978

By L. C. Johnston, J. N. Gills

This paper reviews the basic reactions of the blast furnace and the open hearth furnace, and then discusses the quarrying and sizing requirements of the limestone feed for each. Particular emphasis is placed on the lime-stone at Irish Cove, now being mined under an agreement between Scotia Limestone Limited and Dosco Steel Limited. The drilling and blasting operations are described, along with loading and haulage, plant flow, water supply, power supply and transportation facilities.

Jan 1, 1967

By L. Heber Cole

In making this plea for a better and more sympathetic understanding of the non-metallic industry, I do not for one minute wish to give the impression that I in any way belittle the wonderful strides that have been made in the exploitation of our metallics. We in Canada can be justly proud of our Sudburys, Norandas, Flin Fions, and of the remarkable growth of the Consolidated in British Columbia, and at the same time, without in the !east detracting from these worthy undertakings, be equally as proud of our asbestos, gypsum, salt, and coal deposits, as well as of our building-stone and limestone industries. If, in my remarks, I have occasion to compare the metallic with the non-metallic industry, I do so, not with any idea of dimming the glory which the metallics of Canada have gained- not only in our own country, but in the world at large-but for the purpose? of bringing to your attention the fact, perhaps not very well recognized, that Canada contains deposits of non-metallics well worth y of your serious consideration. In the past 33 years, namely, since 1895, the value of non-metallics produced in Canada has exceeded the value of metallics in 19 of the years, and for the last three years has been increasing rapidly. The war years (1915-1918 inclusive) naturally saw an intensive metallic production, but since that time, with the exception of 1925, when there was a general depression throughout the whole country, the non-metallics have been in the ascendency.

Jan 1, 1929

By W. J. Farley

"The Sherritt Gordon mine is 100 miles north of The Pas in northern Manitoba. Copper-zinc ore was discovered on the property in 1922. Production began in 1931 and continued to June, 1932, when operations were suspended because of the low price of copper. Operations were resumed on August 1st, 1937, and have been carried on continuously from that time to the present (March 1947). The production of metals up to the end of 1945 was copper, 287,129,880 lb.; zinc concentrate (50 per cent) 104,419 tons ; gold, 79,388 oz.; silver, 2,529,974 oz.GENERALThe ore occurs in two deposits, the east and the west. Both are enclosed in gneisses that are highly metamorphosed sedimentary and volcanic derivatives. The rock beneath the deposits, and hence forming their footwall, is gneissoid quartzite; the hanging-wall rock is basic garnetiferous hornblende gneiss. Pegmatite commonly occurs along both foot- and hangingwall peripheries and as isolated blocks and fragments within the ore zone . These blocks and fragments are considered to be residuals of unreplaced host rock .The ore is relatively coarse grained and ranges from the massive to the disseminated type. The metallic sulphides composing these, named in the order of their abundance, are pyrite and pyrrhotite ( 2-1 ratio) , chalcopyrite, sphalerite (marmatite) , and minor chalmeriite; subordinate amounts of gold and silver are recovered . The insoluble content of the ore averages about 35 per cent.Another deposit known as the Bob Lake, much smaller and lower in grade but having very similar relationships, occurs about 3 ½ miles to the northeast of the main Sherritt Gordon ore masses.STRUCTUREThe Sherritt Gordon orebodies are of the replacement type, and lie within a pegmatite sill that has been intruded along a contact between quartzite and hornblende gneiss. The two main orebodies are intimately related, for the east deposit is an erosional remnant of the lower, easterly limit of an orebody once continuous with the west body. The ore lies along the southwest limb of an overturned syncline."

Jan 1, 1954

By Scott Hommema

? Bitumen in the oil sand averages Bitumen 12 wt%; water makes up 4 wt% ? Imperial Oil (operator) and ExxonMobil developing Kearl Leases #6, 36, 87 (~200 sq. km) ? Target resource > 4 Billion Barrels ? 3 Phase development, ~100 kbd per phase High-quality resource ? Surface mineable bitumen ? Average properties (full lease) ? TV:BIP < 8 ? Grade > 12 wt% bitumen ? Ore thickness of 40 m ? Overburden thickness of 20 m Status ? Phase 1 ? Front end engineering and design underway ? Detailed engineering to start 2008

May 1, 2008

By Patricia Dillon

EHS Management Standards Communication and Reporting (8) ! Establish processes for internal and external communications ! Designate responsibilities for communication with COI ! Report as defined by senior management ! Report annually to employees, shareholders, COI on EHS and social performance Community Rights and Public Consultation (9) !Identify COI?s and establish process to hear concerns !Acknowledge and respond to complaints !Support local communities !Plan for closure and conduct public consultation !New projects include identification of COI?s, concerns to be considered in design

May 1, 2004

The Project ? $1.4 billion project ? 59,000 tonnes of nickel and cobalt ? Large resource base ? First production end of 2004 The Place ? Half the size of Vancouver Island ? Population 210,000 ? 43% Melanesian, 37% European, 12% other South Pacific groups, 8% other nationalities ? Tourism principal industry ? 1/3 of world?s nickel resources The Politics ? French Overseas Territory ?1998 Noumea Accord: increased local control over domestic policy ? Referendum on independence in 2014 ? Seeking more economic autonomy, less dependence on French support

May 1, 2002