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By Anthony A. Zoobkoff

Gotcha! ? What Did I Just Agree To? ? You can?t repeat or use anything you heard. ? Did you agree before you knew what you were going to be given, told or shown? ? If you knew what you were to be given, told or shown, would you have still agreed?

May 1, 2013

By F. Habashi

Lead is an ancient metal, has been produced to-date from its ores exclusively by pyrometallurgical route. The process suffers from high operating cost and excessive pollution problems. Extensive research has been going on since the beginning of the twentieth century to find a non-polluting process for its production and a solution for its complex refining scheme. It has been assumed correctly that the hydrometallurgical route should be the most promising. Pilot plants have been constructed and operated for a reasonable periods, but no process has proved to be satisfactory. As a result, a number of smelters and refineries have been shut down. The present review analyses the situation and suggests that the best route to treat lead sulfide concentrates is by leaching with fluoroboric acid, HBF4, containing ferric fluoroborate, Fe(BF4)3, and electrolyzing the solution in a diaphragm cell - - a process recently invented by Italian metallurgists. In this process, any silver present in the concentrate remains in the residue together with elemental sulfur and can be recovered by known methods.

Jan 1, 2008

By Eric Barnard, Andreas Nashitati, John Tero, Guy Deschênes, Setta Mbalamba, John Rajala

The Otjikoto Mine, owned at 90% by B2Gold Corporation, is located 300 km north of Namibia’s capital city of Windhoek. The reserves from the open pit mine, estimated at 25.9 million tons with an average grade of 1.28 g/t Au, contain gangue minerals, pyrite and pyrrhotite, and have an estimated 10 year mine life. The feasibility study included an optimisation of gold leaching using CSTR for the original design. The results of the test work were used to establish the design criteria. Gravity tails from three composites (drill cores), representing the major ore types, were used. The XR3 sample (gravity tails) contained 0.32 g/t Au, while the XR2 and XR1 gravity tails samples (used for variability) contained, respectively, 0.30 g/t Au, and 0.47 g/t Au. The optimum leaching conditions were: a pre-treatment of 7 h at pH 10.5 with 100 g/t lead nitrate, DO > 5 ppm followed by cyanidation at 300 ppm NaCN, pH 10.0, DO > 5 ppm for 48 h. The gold extraction was 91.5% (97.2% overall extraction gravity/leach) and the cyanide addition was 0.57 kg/t NaCN. Increasing the DO to 16 ppm did not show any economic benefits. No pre-treatment or a 4-h pre-treatment reduced the gold leaching kinetics. The XR2 and XR1 gravity tails samples had gold extractions of 92.9% and 92.3%, respectively. At the plant scale, an 11 h pre-treatment is used followed by 42 h cyanidation with 250 ppm NaCN and an average DO of 8 ppm and 230 g/t lead nitrate in 2016. The cyanide addition was 0.49 kg/t NaCN. The commercial operation started on February 28th, 2015. The overall gold recovery and production were 98.4% and 145,696 ounces for 2015 and 98.1% and 166,286 ounces for 2016. It was found that retention times, gold content of leach residues and cyanide addition are comparable for the lab and the plant. Details of the Otjikoto process flowsheet are discussed in this paper along with the results of the lab leach optimisation test program and the plant leach circuit performance and improvements.

Jan 1, 2017

By Mi, Dong Liang, Jingyuan Bai, Victor Zhou, Xujun

Squirrel cage induction motors are the mostly used motors at present. Currently, the rotors of the squirrel cage induction motors are produced by aluminum die casting technique with the advantages of low cost of rotors. It is well known that the copper’s electrical conductivity is around 40% higher than that of aluminum. If copper is used to replace the current widely used aluminum in rotors, the total loss of motors will be reduced, hence increasing the overall motor efficiency. Copper rotors can be used to produce high efficiency and even super premium efficiency motors without enlarge the motor frame size. Considering the huge quantity of motors, the die casting process is the best solution to produce copper rotor with economic cost. Because of the characteristics of copper, it is difficult to produce copper rotors by casting similar to that done in aluminum rotors. In order to improve the die casting quality of copper rotor, a new tooling structure was developed and the casting process of copper rotor was simulated and analyzed by Any-casting software. The filling process, solidification process, inner gas distribution and residual melt modulus were analyzed. It was found that the design of symmetrical runner and inner runner on both sides was helpful to reduce the impact of molten copper to the cavity surface during the filling process. The use of Slag traps array can reduce die casting defects inside the end rings. That will be helpful to improve the rotor quality. INTRODUCTION Squirrel-cage AC induction motors are most widely used in the world. In 2017, the total installed capacity of AC motors in China has reached more than 1.2 billion kW, and the annual power consumption accounts for about 60% of the total national electricity consumption. To improve the efficiency of squirrel-cage motor will be helpful to energy conservation and environment protection. There are several ways to improve efficiency of induction motors, using copper rotor is one of the most effective solutions. It is well known that the copper’s electrical conductivity is around 40% higher than that of aluminum. If copper is used to replace the current widely used aluminum in rotors, the total loss of motors will be reduced, hence increasing the overall motor efficiency. Copper rotors can be used to produce high efficiency and even super premium efficiency motors without enlarge the motor frame size.

Jan 1, 2019

By A. D. Dalvi

Economics, Resources, Environment and Technology are the major driving forces in the base metals industry. However, these factors are intertwined and together will propel the industry in the future. The demand for metals has grown with economic expansion, between 2 to 4 % p.a. The current growth cycle has been driven by economic expansion in China where the demand for base metals has risen from - 7 % of the world demand in the 90's to - 25 % of world demand today, and rising. Base metals are commodities and their demand and price are cyclical. Historically metal prices have declined in constant dollars, forcing the industry to reduce costs, increase productivity and increase the scale of operation for economies of scale. Due to resource depletion and capacity expansion the industry is driven to expand its reserve and resource base. However, in the case of sulphide deposits of copper and nickel it appears to be a losing battle. For nickel the laterites represent a vast source at this time. Their development requires development of new technologies to make these resources economic. Emission reduction is being increasingly mandated in most jurisdictions with all governments enacting progressively more stringent regulations. The industry has been responding with technological innovation. With the Kyoto protocol there is a push to reduce energy intensity in metal production. Technological innovation is driven by all the other factors and is leading to novel ways of doing exploration, mining and processing, that would maximize resource delineation and utilization, reduce costs, increase productivity, reduce energy consumption, maximize asset utilization and reduce environmental affects. Development of alternative technologies such as Pressure Acid Leach of laterite for nickel, bio-leaching, heap leaching, SX-EW etc are being adopted to achieve the aims of the industry.

Jan 1, 2005

By M. E. Holuszko

A research program has been carried out at the Mining Department of the University of British Columbia to study the effect of wettability of coal on its handleability and bulk density. The effect of moisture content on the bulk density of coal was found to be more pronounced for hydrophilic coals than for hydrophopbic ones. Altering wettability of coal surface leads to different effects of moisture on bulk density. The samples were studied at different fine fractions content, and it was shown that there was no effect of increased content of fines on the bulk density for hydrophobic coals, while for hydrophilic coals this effect was very significant. It was shown that the moisture content at which the lowest bulk density was reached coincides with the critical moisture content for studied samples, as determined from handleability tests using Durham Cone method. This critical moisture is the moisture content at which a sudden deterioration of coal handleability occurs. Based on the bulk density and handleability tests, the flow theory of moist coal is proposed.

Jan 1, 2006

By Harold L. Gibson, Don H. Rousell, Ian R. Jonasson

"Abstract - The Sudbury Structure consists of three major components: 1) the Sudbury Basin; 2) the Sudbury Igneous Complex which surrounds the basin as an elliptical collar; and 3) an outer zone of shatter-coned and intensely brecciated footwall rocks. Although the Sudbury Event which formed the structure may be unique, the area has, in fact, been shaped by a series of tectonic, magmatic and mineralization events which can be considered in terms of two Wilson cycles of continental extension and closure. The first cycle, from 2500 to 1700 Ma, included the following events: doming (uplift of Levack Gneiss Complex); NE-SW extension (Matachewan dikes); N-S to NW-SE rifting (faults, mafic intrusions, sedimentation, and Ni-Cu-PGE and U mineralization); NW-SE extension (Nipissing diabase, and Ni-Cu-PGE, Ag, Co mineralization); and NW-SE and NE-SW closure (Penokean Orogeny, 1900 to 1700 Ma) with superimposed meteorite impact (1850 Ma, Ni-Cu- PGE, Zn-Cu-Pb deposits). The second cycle, from 1700 to 1000 Ma, included: N-S extension (alkali metasomatism, Au); N-S extension (hornblende diabase dikes along the Murray fault set); NNESSW extension (olivine diabase dikes); NE-SW extension (Fecunis Lake fault set); and NW-SE closure (Grenvillian Orogeny).The rich and diverse Ni-Cu-PGE and subordinate Zn-Pb-Cu and Au mineralization of the Sudbury region is related to endogenic and impact-triggered crustal extension and magmatism. The Sudbury Structure apparently was the site of a triple junction or hot-spot. The Sudbury ores, although located within an impact structure, are analogous in terms of age and tectonic setting to Ni-Cu-PGE and Zn-Pb-Cu ores elsewhere in the world. Meteorite impact accentuated on-going ore forming processes and magmatism at Sudbury."

Jan 1, 1997

By Harold L. Gibson, Don H. Rousell, Ian R. Jonasson

"The Sudbury Structure consists of three major components: 1) the Sudbury Basin; 2) the Sudbury Igneous Complex which surrounds the basin as an elliptical collar; and 3) an outer zone of shatter-coned and intensely brecciated footwall rocks. Although the Sudbury Event which formed the structure may be unique, the area has, in fact, been shaped by a series of tectonic, magmatic and mineralization events which can be considered in terms of two Wilson cycles of continental extension and closure. The first cycle, from 2500 to 1700 Ma, included the following events: doming (uplift of Levack Gneiss Complex); NE-SW extension (Matachewan dikes); N-S to NW-SE rifting (faults, mafic intrusions, sedimentation, and Ni-Cu-PGE and U mineralization); NW-SE extension (Nipissing diabase, and Ni-Cu-PGE, Ag, Co mineralization); and NW-SE and NE-SW closure (Penokean Orogeny, 1900 to 1700 Ma) with superimposed meteorite impact (1850 Ma, Ni-Cu- PGE, Zn-Cu-Pb deposits). The second cycle, from 1700 to 1000 Ma, included: N-S extension (alkali metasomatism, Au); N-S extension (hornblende diabase dikes along the Murray fault set); NNESSW extension (olivine diabase dikes); NE-SW extension (Fecunis Lake fault set); and NW-SE closure (Grenvillian Orogeny).The rich and diverse Ni-Cu-PGE and subordinate Zn-Pb-Cu and Au mineralization of the Sudbury region is related to endogenic and impact-triggered crustal extension and magmatism. The Sudbury Structure apparently was the site of a triple junction or hot-spot. The Sudbury ores, although located within an impact structure, are analogous in terms of age and tectonic setting to Ni-Cu-PGE and Zn-Pb-Cu ores elsewhere in the world. Meteorite impact accentuated on-going ore forming processes and magmatism at Sudbury."

Jan 1, 1997

Applying DEM to prediction of tumbling mill performance is challenging because several different modes of breakage are active in the process. As our knowledge of breakage and computational capacity improve, it is worth revisiting previous simulation tasks which did not produce a satisfactorily realistic description of a measured process. At SAG 2006, we reported the simulated and measured outcomes of treating a well characterised ore in a 1.2 m diameter mill. This well instrumented, pilot scale mill at the University of KwaZulu-Natal has been combined with some new approaches to ore testing to allow different modes of breakage to be tested. The mill design allows the rate of generation of fine material to be measured in close to real time for autogenous and SAG mill charges. The updated simulation model estimates mass loss with particle evolution and embeds the cumulative damage and breakage. The simulated results are compared with the measured results. Issues such as relating modelling inputs to particle breakage characterisation data and the accuracy of the predictions of the models are discussed.

Jan 1, 2012

By H. Ishimoto

It always has been a serious issue to improve safety in mine sites, demolition work sites, and civil engineering work sites. Especially, collision accidents caused by construction equipment damage not only the productivity of operations but also the health and life of workers in those work sites. To solve this problem, a variety of worker auto-detection means are developed so far, but they have not still become widely used in actual worksites. There have been two controversial points in the prior methods. One is that they were not enough in respect of the detection accuracy and certainty, and the other one is that the information of the detection results was not comprehensible to the operator of equipment. In this paper, the functional requirements of the obstacle detection system in earth moving work site is redefined at first, and then, it is proposed to apply a stereo vision to the obstacle detection system for an excavator. The system consists of horizontally arrayed two digital cameras with low distortion lens, an image processing controller, and a monitor for an operator in the cab. Stereo vision calculates the depth image from images of two cameras and detects the presence of obstacles, its distance, direction, and dimensions. Sensed obstacles are informed to the operator in the monitor image. Preliminary experiments are conducted with a stereo vision system mounted on a real equipment in a demonstration site. The result shows that two controversial points of the conventional technologies are improved, and that the applicability of this system is validated.

Aug 1, 2013

By R. W. Thompkins

In order to evaluate the impact of air quality control on mine design, a few examples are given of cases in wh.ich ventilation has affected the economics of the total design problem. Principles for the drainage of gas contaminants are shown, and the contamination control problems created by differential pressures in complicated booster fan installations are discussed. The paper also deals with the use of advanced mathematics for solving some of the ventilation problems likely to be encountered.

Jan 1, 1967

"SART technology is a useful tool for improving the economics of gold recovery from certain types of complex gold ores. SART liberates cyanide consumed by base metals such as copper, zinc and nickel, and enables the newly freed cyanide to be recycled to precious metals leaching while producing high-grade base metal sulphide concentrates for sale. The benefits of SART include the reduction in cyanide consumption, avoidance of cyanide destruction costs, minimization of risks of environmental non-compliance due to residues of cyanide destruction reporting to mine effluents, and generation of extra revenue from the sale of base metal concentrates. Concerns with SART typically include uncertainties around capital and operating costs and proper integration of SART into the overall metallurgical flowsheet. This paper presents two case studies addressing these concerns. The first involves actual costs of the full scale SART integrated into a gold heap leach operation and treating up to 500 m3/hr of leach solution at a mine in Mexico. The second involves field pilot testing and a preliminary cost estimate for integrating SART into a silver mine in Peru using Merrill Crowe.INTRODUCTION One of the current trends in the gold industry globally is the increasing importance of complex polymetallic gold deposits as discoveries of large Carlin type gold deposits become increasingly rare (Sceresini, 2005). The presence of cyanide soluble copper and zinc in complex gold deposits necessitates changes in traditional gold extraction metallurgical flowsheets. One of the tools available to the industry to help deal with interferences of cyanide-soluble base metals in gold extraction is the SART (sulphidization-acidification-recycling-thickening) process. SART breaks the weak acid dissociable (WAD) base metal-cyanide complexes, precipitates the metals as high-grade sulphide concentrates and makes the freed cyanide available for recycle. Although SART is a commercially available technology, it is still relatively new to the industry. Fewer than ten (10) full scale plants have been constructed in the past couple of decades. Some of these SART plants are small, most are located at remote sites, and the majority have not operated on a continuous basis. This has resulted in a general lack of information in the industry about the true costs, operability and metallurgical performance of SART. BQE Water has been involved in the design, construction, commissioning and operation of large scale SART plants in Mexico, Turkey and Chile and has conducted field testing programs as part of the technical assessment of SART integration into various metallurgical circuits. Having built and operated numerous plants utilizing selective sulphide precipitation of heavy metals, BQE Water has gained unique insight into the design and control of the sulphidization stage of SART to minimize costs and ensure high efficiency in cyanide recovery."

Jan 1, 2017

By P. S. Arthur

The copper I SAS MELT? process is a submerged lance bath smelting technology. In the 20 years since the process was first demonstrated on a semicommercial scale at Mount Isa in north-west Queensland, Australia, copper ISASMELT? plants have been constructed to treat concentrates or secondary raw materials around the world. The process is operating in smelters in Australia, the USA, Belgium, India, Germany, China and Zambia. ISASMELT? plants have been installed to improve the environmental performance of operating smelters and reduce costs for smelting companies. A new copper furnace is being commissioned at Southern Peru Copper Corporation in early 2007, while more furnaces are under design for installation in Kazakhstan and Peru. Copper ISASMEL T? plants are supplied as complete technology packages including engineering design services for the furnace and key ancillaries, supply of core equipment, provision of intensive training programs in operating plant environments and commissioning assistance services. The proven technology transfer process ensures successful implementation of submerged lance bath smelting into large scale plants. This paper summarises developments at recently constructed copper ISASMELT? plants.

Jan 1, 2007

By D. J. Cheung, V. N. Kazakidis

ABSTRACT Seismicity and rockburst problems in hard-rock mines negatively impact safety and profitability. The authors propose a design risk methodology as a relative risk assessment for underground excavations vulnerable to rockburst damage. It considers rock mass conditions relating to mininginduced stress, geological structure, rock mass properties, and mining influence. Application of the methodology to rockburst cases involving seismically active fault zones at the Craig mine in Sudbury, Ontario, Canada, demonstrates that design changes can reduce exposure and economic risks. Mines with high geotechnical risk can use the design risk methodology to evaluate design alternatives as a risk management strategy.

Jan 1, 2014

By S. A. G. Poppen, J. Konopka

"Petro-Canada's project investigative and experimental underground work in the Galt coal seam at Kipp, Alberta included the construction of an emergency egress and ventilation raise from surface.The Galt coal seam is 206 m below the surface and covered by 8 m of shale, sandstone and clay beds of the Oldman Formation, 128 m of shale, bentonite beds and sandstone of the Bearpaw Formation, and 70 m of glacial till and basal gravel. Free water was encountered from sand lenses in the glacial till and the basal gravel.Excavation for the ventilation raise was a nominal 2 m diameter and it was lined with a welded, continuous, steel liner of 1.2 m 1.D.Excavation in the glacial till was carried out with a surface bucket drill rig combined with hand mining. Ground support in the glacial till consisted of liner plates and backfill grout. The Bearpaw and Oldman formations were excavated by employing standard raise boring techniques. The individual liner sections of the continuous steel liner were assembled on surface and the entire liner column was lowered into the raise by employing hydraulic lift climbers. The liner column was back-filled with concrete.IntroductionThe Lethbridge Coal Field comprises an area of approximately 1 165 square km in the vicinity of Lethbridge in southern Alberta. Pacific Petroleums Ltd. proposed in a Preliminary Disclosure in January 1979 ""to open an experimental mine prior to development of a producing underground mine with an initial rate of 540,000 tonnes per year"". A 2 900-hectare group of leases in the Kipp-Coalhurst area was selected as the primary target for the Kipp experimental mine. The scope of work for the experimental mine included the construction of an access shaft with production capabilities, the construction of a ventilation and emergency exit raise, drive-ages in coal to yield a bulk sample, gathering of geotechnical information and the testing of experimental mining methods."

Jan 1, 1983

By X. Zhou

"Hydrogen induced failure and degradation in structural metals, namely hydrogen embrittlement, has been a long-standing industrial problem for more than one century and remains unsolved. Despite the proposal of numerous models, no consensus has been reached, and considerable discrepancies in experimental observations and theoretical calculations exist. One aspect that is central to the understanding of hydrogen embrittlement is the interaction between hydrogen and grain boundaries. In this study, we investigated the influence of several solute elements (i.e., Cr, Mo and Nb) on hydrogen segregation at the representative 9 grain boundary using first-principles calculations. Our results showed that the presence of Mo and Nb can reduce the tendency of hydrogen segregation at grain boundaries, while meanwhile enhance the grain boundary strength. This indicates that Mo and Nb are salutary elements that can be used to increase the material’s resistance to hydrogen embrittlement, providing new insights in designing hydrogen embrittlement resistant Ni alloys. INTRODUCTION Hydrogen embrittlement (HE), a phenomenon of hydrogen triggering premature failures in structural metals, has been a headache for industries ever since its first discovery one century ago (Johnson, 1874; Zhou, Marchand, McDowell, Zhu, & Song, 2016; Zhou, Ouyang, Curtin, & Song, 2016). It is well accepted that the segregation of hydrogen at microstructures such as grain boundaries (GBs) plays a key role in determining the occurrence and severity of HE. GBs are two-dimensional defects where significant local lattice distortion exist, which leads to large free volume and thus locations for hydrogen trapping and segregation. Numerous works have clarified GBs as the energetically preferable places for hydrogen segregation. For instance, Geng et al. demonstrated the preferential segregation of hydrogen at the S5(120) GB in several metals, and suggested a decohesion-type of HE in light of Rice-Wang thermodynamic theory (Geng, Freeman, & Olson, 2001). Birnbaum et al. illustrated that complete intergranular crack of Ni GBs can be induced by hydrogen segregation when the hydrogen concentration is sufficiently high, evidencing the significant role of hydrogen accumulation on GB weakening (Lassila & Birnbaum, 1987). Yamaguchi et al. demonstrated strong segregation hydrogen also occurs at S3 GBs in alpha-iron, showing that local hydrogen clustering (i.e., multiple hydrogen atoms, up to six, per unit cell) can be trapped at the S3 GB (Yamaguchi, Kameda, Ebihara, Itakura, & Kaburaki, 2012)."

Jan 1, 2017

By Keith Jones, Largo Albert

"Decelerometer testing of a rigid guide system in a mine shaft pro vides usefuI information to operating and maintenance people. High acceleration/deceleration rates can lead to high maintenance costs to bath conveyances and shaft and can also present an operating risk . Possible disastrous results in the shaft have been avoided by restricting the maximum conveyance speed until the shaft and/ or conveyance problems have been solved.The test instrument is a valuable aid especially during commissioning or updating of a hoisting installation. High acceleration/deceleration rates also lead to reduced hoist rope life. During the past fourteen years, a total of 15,000,000 feet of testing was performed in 74 assorted shaft compartments.Based on this experience, it is possible to establish acceptable conveyance maximum speeds provided that all other conditions in the shaft compartment are normal. The body of the paper will present examples of several tests made under actual operating conditions.IntroductionMore and more mine operators are recognizing the real value in the use of the decelerometer for determining the state of shaft guide alignment in their shaft compartments , not only during the initial mine start-up periods, but also on a regular basis while the mine is in production.Decelerometer testing, is a technique in which an accelerometer , commonly known as a decelerometer, is used for measuring conveyance acceleration/deceleration in a lateral plane. lts purpose is to determine the severity of shock loads produced by misaligned shaft guides. Testing is performed by mounting the instrument on the conveyance and operating the conveyance (empty and loaded) at various speeds up to and including full speed . However, full speed may not be attained due to conditions indicated by the tests. These conditions may present an operating risk to the plant."

Jan 1, 1984

By J. N. Van der Merwe, M. Mathey

"The development and mechanical characterization of coal-crete, a composite material generated from coal fragments and some binder material, is described in this paper. Coal debris was obtained from a colliery in South Africa. The binder used in the study basically consists of cement and water, and further ingredients are added to the mixtures, such as sand, fly ash and polymers, in order to investigate alterations of the mechanical properties of coal-crete.Results from over 220 mechanical tests on coal-cretes with various binder mixtures give consistent trends for the material’s behaviour. Linear relationships are suggested between the uniaxial compressive strength, Young’s Modulus and the indirect tensile strength of the coal-crete.It is shown that mechanical properties comparable to coal can be achieved. Coal-crete is therefore suitable for physical modelling of mining situations in experimental studies and for use as backfill in underground coal mines. The latter application is particularly attractive when refuse coal is used as aggregate material. The indicated trends in this study may be used as a guideline for individual coal-crete design needs. However, some uncertainty remains as to the influence of particle shape, size and gradation, coal rank and age of the coal-crete. These aspects are recommended for further research."

Jan 1, 2015

By S. W. Marcuson, P. J. Mackey

The 1973 Oil Embargo and succeeding disruptions in supply had a profound effect on energy costs and consumption patterns in the developed world. This was especially true in the USA where post World War II growth, fueled by low-cost imported oil, left the country dependent on uninterrupted oil shipments from the volatile Middle East. In this atmosphere, Professor H.H. Kellogg of Columbia University, convinced of the necessity of good environmental stewardship by the writings of the era’s leading environmentalists, developed a methodology for evaluating energy and process efficiency of metallurgical processes and wrote a series of papers describing and applying the techniques. One of these, "Energy Use in Sulfide Smelting of Copper" is recognized as a seminal work which both described the state of energy usage in copper smelting in the mid-1970’s and portended future developments. The background to these papers is examined and the current and past Cu-Ni matte smelting practices in Canada are examined in the context of the results. Data from early 20th century publications describing reverberatory and blast furnace operation is employed to show that energy consumption for much of the century was several multiples higher than that calculated for best reverberatory operation in the 1970’s.

Jan 1, 2015

By Pierre Bernard

Contents of the presentation ? Overview of Brunswick 12 Mine ? Brief description of the mine geology ? Summary of the current Mineral Reserves and Additional Mineral Resources ? Review of the ongoing mining remnants evaluation process, particularly emphasizing the integrated work between the mine geologists, the mine engineers and the metallurgists ? Challenges and opportunities to extend the mine life

Apr 1, 2005