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By J. Ji, A. Shi, B. Grcic

Floating copper minerals selectively against iron minerals such as pyrite has been challenging for most copper and copper/gold deposits, and many operations continuously strive to maximise copper recovery whilst meeting target concentrate grades. Maximising grade is achieved by selectively floating copper minerals and rejecting pyrite. This challenge is to minimise copper and gold losses in the roughers if this approach is used. A flotation testing program was conducted by Bureau Veritas Minerals on a high-level pyrite bearing copper/gold ore sample to establish the potential to reject pyrite in the rougher stage, but also maximise copper and gold recoveries, and ultimately final product grades. The test program included feed characterization, rougher and open-circuit cleaner flotation as well as locked cycle flotation tests. The main variables tested for achieving selective flotation of copper and gold were collector type and pH control, through lime addition. Grind sizes used in the rougher and cleaner tests had been established from previous test work. The collectors tested were SIPX, Aerophine® 3418A, Aerophine® 3421, Aerophine® 3422, Reagent S-11192 Promoter, Reagent S-11193 Promoter and FloMin C4150. The two best performing collectors were then tested in open-circuit cleaner tests, with the optimum conditions examined further in locked cycle tests. INTRODUCTION Bureau Veritas Minerals Metallurgical Division was retained by Eldorado Gold Corporation to perform a metallurgical testing program on a high-level pyrite bearing copper/gold ore sample from a gold- copper porphyry deposit to optimize flotation reagent scheme to improve gold and copper recoveries and copper content in the concentrate. The test program included feed characterization, rougher and open-circuit cleaner flotation as well as locked cycle flotation tests. Initially, various collectors were screened in kinetic rougher tests, and over a pH range of 8.5 (i.e the natural ore pH) up to 11.5, using a primary grind size of 80% passing 120 µm. The collectors tested were SIPX (sodium isopropyl xanthate), Aerophine® 3418A, Aerophine® 3421, Aerophine® 3422, Reagent S-11192 Promoter, Reagent S-11193 Promoter and FloMin C4150. The enrichment ratio, which is the ratio of copper to sulfur in the concentrate to that in the feed, was used as proxy for rating selectivity (i.e. degree of pyrite rejection or depression).

Jan 1, 2019

By Gordon E. Forward

Sustainable development in the mining and metallurgical industrial sectors can be implemented by two distinct groups: 1. The managers and operators of existing facilities ? working with industrial processes and systems that have been operating for many years, in some cases several decades 2. Those who are engineering and building new facilities or upgrades of existing plants. The focus of this paper is to look at approaches and tools available to bring sustainable development thinking and action to these two distinct areas. The paper will discuss: 1. The concept of working with existing facilities and processes to minimize waste and maximize product from a regional raw material/resource consumption perspective using By-product Synergy. The BPS concept has been carried out in Texas (TXI-Chaparral?s STAR Example), in Calgary, Alberta with Suncor assistance, in Montreal, Quebec with Noranda as project leader and currently in Ontario with Dofasco as industry champion. Successful outcomes are presented. 2. A new approach to designing greenfield facilities or upgrades to existing plants using a sustainable development review process. Undertaking the review early in every project can institutionalize the concept of discussing and implementing waste elimination, design for environment, eco-efficiency, risk minimization and community awareness and involvement in the future capital stock. The review process has been developed as an excellent tool for measuring and reporting on a corporation?s sustainable development progress. Examples of how this approach has been adopted in the mining and metallurgical industry, and the resultant outcomes are given.

May 1, 2002

By D. O. Downing

"The 1990s saw enormous changes in the Canadian coal industry and the future promises to be no less turbulent. While the markets served by Canadian coal producers have changed and buying practices continue to evolve, the coal mining, or supply side, has also changed remarkably in response and now provides the basis for an interesting industry story.The dynamic situation in coal mining has led to some surprising outcomes and seemingly contradictory developments. This paper outlines the changes that have occurred, and which are still unfolding in Canadian coal mining, firstly, in terms of mining technology and productivity, secondly, in terms of corporate divestments, acquisitions and bankruptcies, and finally, in terms of resource development. The paper also outlines some plausible futures for the industry looking ahead."

Jan 1, 2002

By B. Tiryaki, M. Ayhan, O. Z. Hekimoglu

"This paper discusses the aspects of tracking cutters related to the computer-aided design of shearer drums. A comprehensive computer analysis of drum dynamic parameters for multi-tracking tool arrangement is not presently available, as the current computer programs mainly consider the aspects of single tracking. Despite the fact that the single-tracking arrangement is recommended for efficient cutting, some major drum manufacturers have been seen to persistently adhere to multi-tracking, probably due to a lack of information. Further studies in this field are believed to contribute greatly to the current understanding of the computer-aided design of shearer drums.A number of laboratory simulation trials and long-term underground investigations were carried out in detail on tracking cutter arrangement, and an equation required for a computer program was derived. The results obtained from computer assessment of dynamic parameters for drums with multi-tracking arrangement were found to be in accordance with those of the underground trials, indicating the validity of the equations. The procedure adopted for the computer appraisal of the shearer drums designed with a multi-tracking concept, as described in this study, is therefore recommended to be considered in the currently employed computer programs."

Jan 1, 2003

By Karl J. C. Harries

"9.1. INTRODUCTIONIn Chapter 5 of Volume I royalties are dealt with and several topics would appear to be duplicated in this Volume. However, Volume I may be looked upon as a general guide, whereas this Volume is a reference volume. It deals in considerable detail with specific provisions and concepts relating to royalties between private parties. This does not, however, mean that Chapter 5 can be ignored. It should be looked upon as a source of general information concerning royalties between private parties and as a negotiating aid intended to give an overview of various topics. You may well find that in its general approach it will lead you to ask a question which, hopefully, will be dealt with in this Volume .It should be remembered that royalty agreements are agreements with a particular focus, and so the concepts set forth in Chapter 1 apply to them. This chapter addresses a few considerations specific to royalties that will usually form part of an agreement rather than a stand-alone agreement.9.2. FORMAT FOR ROYALTY PROVISIONSIn many of the cases where royalties arise, they are adjunct to, or part of, other arrangements. For example, a royalty may form part or all of the consideration to be given to an owner upon purchase of his property, or it may arise if a joint venturer ceases to contribute to the venture and has his interest converted to a royalty.1 It is with such situations that this section primarily deals; if the royalty is contained in an agreement that is singularly, or primarily, concerned with creating it, then it is just a normal agreement.Commonly, by the time the right to receive the royalty arises, at least some of the other provisions of the agreement have been performed and/or become redundant. For example, in an option agreement the royalty will be a continuing obligation of the optionee, usually arising only after the option has been exercised.2 In a joint venture agreement, a royalty will often arise where the interest of a non-participating venturer has been diluted and converted to a royalty, in which case the recipient will usually become a passive party, entitled only to his royalty, and most of the rights that he enjoyed as an active venturer will cease to be effective."

Jan 1, 2003

By Phil Thwaites

"The mining industry uses many types of mineral and metallurgical plants to produce saleable product from ore mined. Plant design history has left current operations with a mixture of manual operation and various forms of automated process controls. Consequently, we typically see high variability in the continuous operations together with a shortfall in the attainment of full capacity, or higher utilization of consumables.At a level of best practice, “Operational Performance Excellence” focuses on process control, using automation and control systems to deliver process optimization. This more sophisticated delivery is a great deal more difficult than the first stage of equipment selection / installation. It includes the appropriate selection of the right instrumentation, control system, key process knowledge, individuals with a solid control engineering background/experience, and the essential backing/ support of the operations management team together leading to higher value delivery. Robust solutions can be realized, considerably minimizing process variation, thus leading to process optimization. This approach results in an easier, efficient and safer process while providing considerable returns for the plant owners.How variable are your processes, and do you maintain optimized process performance with dedicated resources, modern instrumentation, ‘best practice’ control systems and performance monitoring tools? In this lecture, these questions and their possible answers are discussed.357"

Jan 1, 2013

By M. E. Sirkka

"INTRODUCTIONInco Ltd. has ten operating mines in the Sudbury district. Over the last ten years mining methods have changed at Inco with special emphasis on the introduction of bulk mining replacing conventional mechanized cut-and-f ill and undercut-and-fill methods. At the same time, the technology and size of LH D equipment has also progressed to meet the demands of bulk mining. This paper will concentrate on various aspects of the introduction and operation of electric LHD equipment a t Inco Limited, Ontario Division. BackgroundInco Limited received its first electric 2 cu. yd capacity LHD in July 1975 at Creighton Mine. The unit was tested pulling shrinkage stope muck and then was moved to a mechanized cut and- fill complex on 6600 Level. The electric scooptram received quick acceptance from the operators, due to its quiet operation and low heat generation, in a relatively hot operating environment. Although there are only two of these units operating a t present, this initial favourable experience, both in cost and efficiency, led to the development and purchase of electric scooptrams of the 5 cu. yd size. There are currently eleven 5 cu . yd electric LHDs in operation.The most recent development a t Inco is the move to yet larger electric LHDs in the 8 cu. yd size. The first electric ""Eight"" has now been in operation at Copper Cliff South Mine for over a year. This unit has the distinction of being the first one of its kind in service in North America. At the time of writing, there were ten 8 cu. yd electric ma chines operating in Inco's Ontario Division Mines, with three on order."

Jan 1, 1989

By Francis Chartrand

The Kwyjibo deposit is an iron oxide Cu-REE-F-Mo-Au mineralization of Mesoproterozoic age located in the Grenville Province approximately 120 km NE of Sept-Îles, Quebec (Figure 1). Occurring along the SE margin of the Canatiche granitic complex, the deposit is composed of several polymetallic showings that are related to different textural facies of magnetite. The mineralization process at Kwyjibo is complex, and is divided into Early Granitophile, Magnetite, Main Polymetallic and Specular Hematite stages (Cayer et al., submitted for publication). The Main Polymetallic stage, comprising chalcopyrite, pyrite, fluorite, molybdenite and REE-bearing minerals, is superimposed on pre-existing magnetiterich rocks. Discovered by SOQUEM Inc. in 1993, the Kwyjibo deposit shares many characteristics with other hydrothermal polymetallic iron oxide deposits around the world. Foose and McLelland (1995) suggested that this class of mineralization could occur in the Grenville Province. However, only a few polymetallic occurrences are known to be associated with low-Ti iron oxide deposits in the Grenville. Kwyjibo is one of the most significant examples of a polymetallic iron oxide deposit to have been found in the Grenville Province to-date.

May 1, 2003

By Aleksandar D. Bugarski

Despite extensive research efforts conducted in the past decades, occupational health risks associated with exposure to nano and ultrafine aerosols emitted by diesel power equipment are still not completely understood. The complexity of physical and chemical properties of diesel aerosols, constantly changing with the implementation of advanced diesel emissions control technologies, make this task rather challenging. The objective of this paper is to identify and characterize nanometer and ultrafine aerosols emitted by diesel engines in the underground environment and evaluate the effects of selected contemporary control technologies on physical properties, chemical composition, and in-vitro toxicology of diesel aerosols. The physical and chemical properties of the nanometer and ultrafine diesel aerosols are to be characterized through a test series in the NIOSH Lake Lynn Laboratory experimental mine. The crucial part of the study has been development of a facility that allows researchers to generate field results with precision and accuracy characteristics of a laboratory environment. The knowledge obtained from this study should strengthen our understanding of the health implications related to exposure to diesel particulate matter and aid in assessing the potential of various control technologies for reducing this exposure.

May 1, 2007

By Kathleen A. Altman

"This paper supplements the information provided annually at the Canadian Mineral Processors Operators Conference regarding the education of Mineral Processors in Canada. The purpose of the paper is to provide information regarding the engineering accreditation process in the United States and the universities that offer programs in Mineral Processing and Extractive Metallurgy in the U.S.There is a critical shortage of trained Mineral Processors and Mining Engineers world wide. The Society for Mining, Metallurgy and Exploration (SME) formed a task force to evaluate the national needs for trained engineers and to track the number of engineers who graduate from U.S. universities each year. The statistical information for Mining Engineers is well-developed. The current effort is to assemble similar information regarding students who graduate with expertise in Extractive Metallurgy and Mineral Processing as well as to explore the limitations of the accreditation system in the United States and its impact on the education of Mineral Processors. The long-term objective is to develop a data base regarding Mineral Processing programs and Mineral Processing graduates that is as complete as the one that has been maintained by the Canadian Mineral Processors.INTRODUCTIONIn the United States engineering curricula are accredited by ABET, which was formerly known as the Accreditation Board for Engineering and Technology. The objective of ABET accreditation is to ensure that educational programs in applied science, computing, engineering and technology meet quality standards set in conjunction with the professional organizations that represent professionals in the industries which hire students graduating from those educational programs. For example, the Society for Mining, Metallurgy and Exploration (SME) is the lead society for accrediting Mining Engineering programs in the U.S. For Materials Science and Metallurgical Engineering programs, the lead society is The Mineral, Metals and Materials Society (TMS). SME is a cooperating society for accrediting Metallurgical Engineering programs. Cooperating societies for the accreditation of Materials Engineering include the National Institute of Ceramic Engineers (NICE), the American Institute of Chemical Engineers (AIChE) and the American Society of Mechanical Engineers (ASME)."

Jan 1, 2008

By Bryan Wilson

Background ?Nickel Rim South Mine started production ramp-up in Q2, 2009. ?The main dewatering pumps were put into use in August 2009. ?3 Feluwa?multisafe?positive displacement pumps ?1700m single lift pumping ?Reliability has been an issue due to the amount of slimes and fibers (from shotcrete) at the pumps. ?Critiqued internal dewatering system to solve some issues we were having with our sumps Findings 1.Much of the final dewatering system was not in place. a)Temporary pain. Difficult to say something is not working when the system was not yet in place as per design. b)Not enough capacity to handle slimes within the system. 2.Need to address issues with the final design: a)Ongoing costs: The end design has operating costs of $2.5 million b)Scoops in Sumps: The end design relies on scoops to be used for cleaning the sumps c)Slimes Recovery: The system mixes 3 different products in the sumps along with the fibers d)Pump repair costs: The existing Tsurumi pumps are too light duty for our slimes

Nov 1, 2011

By D. Van Tonder

ABSTRACT The comparative economics of ion exchange and direct precipitation have been analyzed by developing indicative CAPEX/OPEX models for typical alkaline leach uranium circuits. An agitated tank ore leach application is considered, comparing resin-in-pulp and direct precipitation as recovery options. Capital and operating cost estimates are derived from rates and factors used in recent studies and projects. The analysis showed the main economic drivers to be the ore grade and resin loading. The resin loading is impacted by the prevalence of competing ions, especially chloride. At resin-in-pulp solution chloride concentrations below 3 g/L and uranium grade below 640 g/t U3O8, resin-in-pulp is more economical, whereas at chloride concentrations above 3 g/L, direct precipitation is more economical.

Jan 1, 2012

By Glenn D. Lyle

As part of an initiative to improve value in mining, CEMI is developing a handbook on best practice in mine design. Various formats were examined, and of these, the wiki was selected as being most suitable. Being web-based, its global reach and capability of being continuously updated allows the wiki to evolve as new knowledge is generated, and to capture the diversity of experience of practitioners in the mining industry. While wikis have many advantages in terms of organizing content and searching, their ability to be edited by users is often seen as a negative characteristic for quality control. To ensure reliability of information content, author attribution, specific authorship models, and a peer review process have been implemented, in addition to the standard version tracking capability of wikis. The first phase of the project concentrates on topics related to underground hard rock mine design. The scope will be expanded to cover other aspects of mining as the project matures. Strategic partnerships with various organizations, such as the CIM, and CANMET, are being formed to provide a wide range of seed material to stimulate growth of the site. www.minedesignwiki.org

May 1, 2011

By J. Paraszczak

For mining companies facing strong international competition and unfavourable commodities’ prices, automation of underground operations has the potential to increase productivity and help cut costs. However, despite considerable technological progress in this field, there still remain many problems to overcome. Furthermore, successful implementation of automation depends also on numerous operational, organizational, and even human factors. In this context, this paper briefly reviews technological progress with regard to different underground operations. Following that, several issues related to implementation of automated equipment and systems are presented and discussed. Particular emphasis is put on the factors whose importance is often underestimated. Some recommendations in this respect are also given. It is stated that the success of an automation project is a function of many “winning conditions,” which may be created through very thorough planning and preparation. It is also underlined that despite achievements made, a vision of a man-less underground mine is not yet as much a matter of near future as it may seem.

Jan 1, 2004

By Jean-François Lessard

The performance of rock pass systems has a significant contribution to the economics of underground mines. Operational concerns include hang-ups due to arching of material, blockage and degradation of the rock pass. This papers presents the preliminary results of a comprehensive rock pass database on the engineering and operation of rock pass systems in Quebec underground mines.

May 1, 2002

By Vincent Jourdain

Located in the James Bay Territory of Quebec (figure 1), the Clearwater property is jointly owned by SOQUEM Inc. and Eastmain Resources Inc. Exploration on the property since the early 70's has resulted in the discovery of several gold showings. Exploration work by the joint venture since 1995 has led to the definition of the Eau Claire Zone containing an indicated resource of 540 000 tonnes grading 11.1 g/t Au (8.7 g/t Au cut at 34.28 g/t Au). Hosted by the archean Eastmain Greenstone Belt, the property geology is dominated by mafic volcanics containing thin horizons of felsic volcanics and/or sedimentary rocks (figure 2). The sequence is metamorphosed to the amphibolite facies and contains two small toalitic intrusions. Regionally, the structural trend is oriented E-W but in the area of the Eau Claire Zone a second trend oriented NE-SW is also present. The first exploration work on the property was conducted by SEREM and SDBJ from 1973 to 1976. It consisted of an airborne electromagnetic survey and a ground follow-up program on several grids. This program, comprising geological mapping, geophysics and drilling, led to the discovery of the Natel showing where a drill intersection returned 8.89 g/t Au over 2.65 m. From 1978 to 1985 the area was withdrawn from staking because of the hydroelectric projects of the James Bay. In 1985, Westmin Resources Limited and Eastmain Resources began an exploration program based on a helicopterborne electromagnetic survey. Once again, a ground follow-up program was conducted on several grids. This program included a soil geochemical survey that identified a strong (up to 10 g/t) gold anomaly. Drilling of the anomaly led to the discovery of the Eau Claire Zone where resources were estimated at 270 000 tonnes grading 6.1 g/t Au at the end of 1990. In 1995, SOQUEM Inc. took an option to gain a 50% interest on the property and obtained its interest in 1998. Since 1995, two principal mineralization zones were identified on the property. The "Rosemary Zone" consists of veinlets and disseminations of pyrite and chalcopyrite within a magnetite-rich amphibolite. The mineralized zone was identified by stripping within an area of 1000 by 500 metres. Drilling indicates copper grades up to 0.32 % Cu over 49.2 m. with locally grades of 0.75 % Cu over 5.9 m. The mineralised zone is associated with QFP dykes and corresponds to a strong magnetic anomaly and a strong copper and molybdenum soil anomaly. The "Eau Claire Zone" consists principally of a set of gold bearing quartz-tourmaline veins oriented E-W and dipping at 45-50??to the south (figure 3). More than ten different veins are recognised in the zone and up to eight veins were observed in a single trench (figure 4). The host rock between the veins shows a degree of deformation similar to the regional volcanosedimentary rocks. Each vein is hosted by a unit of actinolite-tourmaline-biotite schist up to one meter thick. The veins and their hosting schist clearly cross-cut the schistosity of the hosting lithologies and the contacts between amphibolites and felsic to intermediate rocks. Usually, the veins are less than a meter thick and are composed of quartz, tourmaline and calcite. The proportion of quartz and tourmaline varies from 0 to 80% within a single vein. The veins commonly show massive, banded or brecciated texture. Sulphides, mainly pyrite, pyrrhotite and chalcopyrite, generally form less than 5% of the vein material.

May 1, 2001

By Steve Lalancette

Centre Jardin Lac Pelletier (CJLP) has been a leading actor in the revitalisation of closed mining sites in northern Québec for over 20 years. Over that period, CJLP developed a cost-efficient technique that transforms sterile mining residue into a substrate able to support a resilient ecosystem. Using a unique mix of organic matter, fertilisers and selected plant species, this technique rapidly builds a microorganic fauna and a layer of humus that will sustain the creation of vegetation coverage. The coverage is composed of over 13 different plant species, each having a unique role in the development of a resilient ecosystem, from soil stabilisation to nitrogen fixing. Considerably less expensive than traditional methods using civil engineering techniques, it does not require the use of heavy machinery or the spread of topsoil. This technique has been successfully used to restore over 20 sites in Québec such as Joutel, Yvan Vézina and Louvicourt. It is a proven technique that has passed the test of actual implementation. The presentation will review the biological, production and economic aspects of the technique through the revitalisation of the Joutel site.

May 1, 2011

A brief description of the hydro-gen reduction of nickel from ammoniacal solutions by the Sherritt process is given, indicating how this procedure can now be used to coat a great number of materials -particularly powders -with nickel or cobalt, whereby so-called composite powders are produced. The technique for the production of composite powders is described, particularly with regard to the surface activation of noncatalytic powders, whereby it is possible to coat core powders uniformly with nickel or cobalt. The properties of some of the more interesting composite powders, such as Ni/ AI, Ni/WC, Co/WC, Ni/Graphite and i/P, are discussed as well as possible fields of application for these new products. INTRODUCTION DURING the last decade, no-table advances have been made in pressure hydrometallurgy, so that large quantities of three of the more com1r.on metals, copper, cobalt and nickel are now produced on a commercial scale by hydrometallurgical processes.

Jan 1, 1963

By S. V. Ulianov, A. Y. Senchenko, A. A. Shvets, A. V. Aksenov

Development of an efficient technology to process complex ores containing gold and antimony as well as silver is described in the paper. The results from the testwork aimed at the valuables recovery by means of flotation are presented. A process sample of antimonite gold-bearing ore was studied in TOMS institute aiming at development of a technology to process such an ore with generation of antimony concentrate and sulphide gold-containing concentrate. Material composition study indicated that the ore included 5.3% of sulphides: arsenopyrite – 2.4%, pyrite -2.4%, and antimonite – 0.5%. Gold is present as an isomorphic dissemination in arsenopyrite. At sighter testing stage a direct selective flotation flowsheet was chosen to process the ore. Antimonite flotation was activated due to addition of lead nitrate. A single cleaning of a rougher flotation concentrate resulted in antinomy concentrate with 30% Sb content and 71% recovery. Au recovery into antimony concentrate did not exceed 1%. Sb flotation tailings were used to float the remaining sulphides and gold. The resulted sulphide concentrate was characterized by Au content of 20 g/t at about 80% recovery, arsenic content - 10% at ~80% recovery, and sulphur content - 18% at ~81% recovery. The sulphide concentrate can be forwarded to further processing aiming at gold recovery. Given that the concentrate is highly refractory it should be pretreated (bacterial or pressure oxidation, Albion process) prior to cyanidation in order to liberate gold from sulphides. The proposed technology allows one to solve the problem of precious metals recovery from antimonite ores.

Jan 1, 2016

By R. Laplante, P. Radziszewski, P. De Ciccio

"Predicting the effect of wear can lead to improved control strategies that can possibly minimize the risk of catastrophic failure due to wear while maximizing useable life. In the field of geological exploration, diamond drill rod wear illustrates just such a case. Wear conditions vary with geological formations and compositions. The objective of this paper is to determine a general relationship, based in theory and practice, that will approximate drill rod wear and therefore predict remaining drill rod life in the context of Canadian, Australian and South American drilling campaigns. Simulation results allow the definition of simple graphical tools that permit the estimation of the potential drill depth remaining on a given drill rod string. IntroductionWear, in many industrial processes, is an undesired phenomenon for which enormous efforts are made to control, if not eliminate. However, wear, in many other cases, is an intrinsic phenomenon of the given process. In such cases, predicting the effect of wear can lead to improved control strategies that can possibly minimize the risk of catastrophic failure due to wear while maximizing useable life. In the field of geological exploration, diamond drill rod wear illustrates just such a case where abrasive conditions vary with geological formations and compositions.A number of studies have been published on drill rod wear especially with regards to the petroleum industry over the last thirty years (Lewis, 1968; Rollins, 1968; Smith, 1978; White 1978; Rowe and Wilson, 1981; Cheng, 1982; Eustes, 1986; Dudman et al., 1989; Besaisow et al., 1990). Of these, most studies covered management techniques (Rollins, 1968; Smith, 1978; White, 1978; Rowe and Wilson, 1981; Besaisow et al., 1990) and some described case histories (Cheng, 1982; Eustes, 1986; Dudman et al., 1989). However, little (Lewis, 1968) was presented that could aid in predicting wear in the particular case of diamond drilling in the metal mining industry.The objective of this paper is to determine a general relationship, based in theory and practice, that will approximate diamond drill rod wear and therefore predict remaining drill rod life in the context of Canadian, Australian and South American diamond drilling campaigns."

Jan 1, 2002