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By Jean-François Dorion

In an underground mine rock reinforcement elements and surface support units are often exposed to conditions that make them susceptible to corrosion. These unfavourable conditions include high relative humidity, the presence of dust and various other particles in the atmosphere, splashing of water and gases from blasting and diesel equipment. The corrosion of support systems is often associated with a loss in capacity that can be a major safety and economic concern in underground mines. A support system is composed of several components such as bolts, mesh, plate, retaining nut, cable ties. Every individual component can deteriorate due to atmospheric or aqueous corrosion and consequently can damage the integrity of the support system. This paper reports the results of a 5-yr study on the loss in capacity of individual support and reinforcement components at selected underground hard rock mines. As part of this investigation corrosion coupons were installed at selected locations at participating mines. A number of these coupons were recovered at regular time intervals and analysed for any signs of corrosion and subsequently tested to quantify any loss in capacity. The testing of the corrosion coupons was complemented by similar tests on recovered mesh and friction bolt specimens from the site. The collected data have provided useful insights on the factors that contribute to the corrosion of support systems. This knowledge can aid in the selection of appropriate support strategies and a reliable assessment of the predicted useful life of a support system and the need for rehabilitation.

Jun 1, 2012

By Michael Boyle, John Zeni

"The Blind shaft boring method is a mechanised process of excavating large diameter vertical shafts downward from the surface. It is a rotary drilling technique eliminating any requirement for personnel to enter the shaft or access underground workings during drilling and lining phases. Excavated material is delivered to surface carried by a flow of circulating fluid through the centre of drill rods. The drill assembly is suspended from a large A-frame rig and powerful winch at ground level providing vertical thrust to a hard rock cutter head. INTRODUCTION The Southern Coalfields Ventilation Shaft was constructed at a mine, 45 km north-west of Wollongong. The 5 m finished diameter (6.2 m drilled) shaft reaches a final drilled depth of 517 m, the deepest, fully lined blind bored vent shaft to date in Australia. Operated by a mining company in the Southern Coalfields, the expanding mine required a new ventilation shaft and associated surface infrastructure to service future operations. An assessment of future ventilation requirements for the coal seam operations identified a need to improve the capacity and reliability of the existing underground ventilation system in order to ensure a safe and efficient underground working environment. Installation of the new upcast ventilation shaft was determined to be the most cost effective and reliable solution to provide adequate ventilation for underground operations. The completed shaft is smooth and fully lined with steel/concrete composite liners that are hydrostatically sealed. The shaft lining is designed to meet the mine ventilation requirements for a service life of 20 years. The shaft intersects the top of the working section of the coal seam at approximately 513 m of depth. This includes the shaft collar depth and shaft bottom profiled intake section.PROJECT METHODOLOGY AND INDUSTRY BEST PRACTICE The shaft was drilled using the blind bore method, an innovative construction technique and an alternative to the traditional methods of sinking deep and large diameter shafts, such as raise boring and conventional drill and blast shaft sinking. The blind bore method allows the shaft to be drilled from the surface down without anyone having to enter the shaft or the mine during the construction process. This is by far the safest method of shaft construction and is especially suitable for difficult ground conditions where there may be unstable or water-charged strata. As this method involves drilling from the surface downward, shafts can be completed ahead of the underground mine development. Thus, allowing underground operations to focus on development and production without the conflicts of managing ventilation priority for underground contractors and mucking out spoil from excavation workings."

Jan 1, 2019

By M. A. Cristovici

"In the last few years CANMET has taken the initiative by investigating the possibility of reactivating abandoned old tailings dumps (for gold production) which would be of potential economic interest across Canada.Nova Scotia was one location where numerous gold processing plants were in operation in the early days. A survey of the old tailing dumps was conducted and some areas of interest were selected. Among them were the sites identified as Lake Charlotte and Forest Hill.Ore samples collected from those tailing ponds were examined for their chemico-mineralogical composition and investigated for gold extraction. Three technological concepts were tested: flotation, direct cyanidation and flotation followed by cyanidation of the flotation concentrate. The combined flotation- cyanidation variant, yielding a gold recovery in the range of 90%, was recommended for processing the tailing ore.Pilot-plant runs carried out by a commercial testing firm (data not included in this paper) confirmed the conditions and results of CANMET's technology.As a result a consulting-engineering firm designed the processing plant which is expected to begin operation in the near future.IntroductionIn the last few years CANMET initiated a research program to locate in Canada, abandoned gold-silver tailing dumps of potential economic interest and to explore the possibility of recovering the precious metals from these old deposits by modern techniques.A literature search revealed that the first production of gold in Canada was recorded in British Columbia in 1858 and that, production prior to 1900 was essentially restricted to the Yukon, British Columbia Nova Scotia and Quebec. During the early 1900s, Ontario, Manitoba and the North West Territories joined the ranks of the gold producers.Early milling and recovery methods were mainly restricted to sluice boxes, gravity stamps and amalgamation. Froth flotation and cyanidation were introduced at about the turn of the century.Recovery of gold at plants using flotation and cyanidation was very good, therefore the tailing ponds resulting from those operations would, very likely be of little or no economic importance. However, the gold recovery at the amalgamation and gravity concentration plants appeared to be lower, indicating the possibility that significant amounts of recoverable gold would have been carried with the tailings to the dump sites."

Jan 1, 1986

By Hans Lundberg

An electric survey from a 'plane flown over the ground is much faster and cheaper than an electric survey carried out on the ground. The results are obtained as continuous recordings that are resolvable into both a depth expression and a conductivity effect, so that the indications are easier to evaluate, as well as to correlate from one flown line to the other. The prospecting technique adopted in our electric airborne surveys may be brie fly described as follows: A loop of many turns of insulated copper cable is fastened around the fuselage of the 'plane and connected to a generator supplying a few ampere alternating current, usually of a frequency less than 1,000 cycles per second. Just as the current in the primary coil of a common transformer will induce current in the secondary coil when shorted, the alternating magnetic field from this primary current now induces alternating current in electric conductors that happen to be located in the vicinity of the path over which the 'plane is flown. This induced secondary current in each conductive section of the ground causes, in turn, an alternating magnetic field, secondary field, which disturbs or dampens the normal alternating magnetic field from the primary loop flown by the 'plane. These secondary fields are then picked up and recorded by the help of detecting solenoids, amplifiers, and recorders carried in the 'plane. By closer study of such a secondary field it is possible to localize the secondary current causing it and, thereby, the conducting body that contains the secondary current. In the 'plane are continuously recorded, besides the amplitude or intensity of the field, also the phase, which is a measure of how much the recorded secondary field is out of step with the primary field.

Jan 1, 1950

By C. J. Havard, G. C. Taylor, D. G. Cook, N. C. Ollerenshaw, D. K. Norris

"The area encompassed by this report is the eastern and northern Cordillera, shown on the composite map accompanying these background papers. It extends from the 49th pm•allel to the Arctic Ocean and from the Rocky Mountain and Tintina trenches to the Interior Plains. The Mackenzie delta is included in the discussions because of the implications of the bedrock geology of the Arctic Plateau and Coastal Plain on the hydrocarbon and mineral potential beneath it.The eastern and northern Cordillera forms the back-bone of the Western Canada sedimentary basin and from it most of the principles of orogenesis and epeirogenesis relating to the understanding of the structural, depositional and fossil record of the basin have been derived. It may be divided roughly into two parts, reflecting basic differences not only in structural style but also in mineral potential. The more easterly and younger rocks generally contain hydro-carbons, coal and non-metallic minerals; the more westerly and older rocks contain metallic and industrial minerals."

Jan 1, 1970

By D. Laguitton

The basic chemistry of a1•senic related to its dissolution and subsequent precipitation in gold-mine waste waters is discussed. The lime addition methods provides the most economic treatment of arsenical slurries, but requires a careful control of the oxidation of Asm into Asv, of the pH (>12) and the filtration of the precipitate. If arsenic levels below 0.5 mg/ l are required, a modification of the method by phosphate addition must be considered.

Jan 1, 1976

Despite the fact that mined minerals and gemstones have allowed human beings to continuously improve their standard of living throughout the ages, mining has also been implicated in violent conflict for two principle reasons. The first is that mineral resources have been used or traded to conduct or finance violent conflict from small to large scales. The second is the substantial social, economic and environmental changes that occur in a community or a region as a result of mining activity which can either precipitate or re-awaken latent conflict. A modern complication of mining-related violent conflict is the trend for activists, international NGOs and intergovernmental organisations (e.g. the United Nations) to regard any human consequences of resource extraction in terms of Human Rights violations. Acknowledging but not labouring the Human Rights implications of mining-related violent conflict, this paper explores whether or not there is a relationship between the actual or perceived value of mineral resources and the level of violence that occurs in mining-related conflicts. Key to the investigation is a mapping exercise of mining related conflict from 2005 ? 2012: to see where mining related conflict is happening; to identify precipitant causes of mining related conflict; and, to discover what correlation ? if any ? there might be in the degree of violence and the value of the mineral(s) implicated. Findings of the analysis are presented in this conference paper.

Aug 1, 2013

By J. A. Espinosa-Guillen, J. A. Lopez-Molina, S. García, J. A. Valencia-Quintanar

"The design and implementation of grouting treatments in rock masses are procedures that require continuous adjustment of parameters and criteria to optimize the results. In this proposal we describe a set of tools that enhance decision-making for this type of jobs particularly in dam projects. The methodology is focused on hydrogeological zoning of the site and its constant update combining engineer’s experience with artificial intelligence techniques to integrate the site knowledge; as well as the evaluation of grouting results for different scrutiny scales, with special attention on the relationship between water absorption and grout consumption. INTRODUCTIONSeveral methodologies for design, implementation and evaluation for grouting rock masses have been developed for the solution of specific problems and tested in diverse geological conditions. Each of these methodologies is focused on results evaluation for different scrutiny scales (Table 1) and is employed to assist decision-making before or during the grouting process.Some methods define specifications for grouting each stage of the borehole, making theoretical, semi empirical or experience-based considerations to define basic parameters as maximum pressure, maximum volume, grouting time, flow rate, etc. Ultimately each approach aim to optimize the injection process, adjusting volumes or the grouting time required to obtain satisfactory results, reducing risk of creating new flow paths or unnecessary grout travels, and enhancing the mixture properties to achieve adequate penetrability and long-term behaviour. Some of these criteria have been widely used in dam projects, for example the concept of Grouting Based on Facts to define the maximum pressure and volume (Ewert, 1997), the GIN method (Lombardi & Deere, 1993; El Tani, 2012), or the North American standards based on Apparent Lugeon measures (Naudts, 1995; Bruce 2011); on the other hand, there are relatively new criteria that have shown good results for dam grouting as the Aperture Control Method (Bonin et al., 2012; Carter et al., 2012) or the Real Time Grouting Control Method (Stille et al., 2012)."

Jan 1, 2015

By C. A. Morais, L. V. Resende

"The technological development observed in recent years has stimulated the application of rare earth (RE) elements. Amongst their various applications it is well worth mentioning their use in electronics, superconductors, nuclear medicine, as well as in special inks - as those used in radar invisible airplanes. TV and computer monitor screens present as coating a powder containing some rare earth elements, mainly Europium and Yttrium. The recovery of the RE elements from electronic scrap is extremely important as the economic and environmental issues are concerned. This paper describes the study of the Eu and Y recovery from e-scraps. The first step of the process was the leaching of the powder obtained by manually scraping the inside surface of the screen. After the optimization of the leaching, the dissolution of Eu and Y was higher than 98 w/t% and a pregnant sulfuric liquor containing 11.9 g L-1 Y and 0.72 g L-1 Eu was obtained. The second step was the separation of the metals found in the liquor by the solvent extraction technique. The separation of Eu and Y was carried out in a counter current circuit compound of 3 extraction stages, 7 scrubbing stages and 15 stripping stages. DEHPA was used as the extractant, whereas a diluted sulfuric acid solution was applied as scrubbing agent and a hydrochloric acid solution at high concentration was used as the stripping agent.INTRODUCTIONThe rare earths (RE) are a moderately abundant group of 17 elements composed of lanthanides, scandium and yttrium. Amongst the RE, promethium (Pm) is extremely rare, however several of the RE elements are not very rare and occur dispersed in a variety of forms (Greenwood & Earnshaw, 1984; Tyler, 2004).The innumerable applications of the RE elements are based on their particular properties, mainly their spectroscopic and magnetic properties (Martins & Isolani, 2005). The technological development observed in recent years has stimulated the application of rare earth (RE) elements. They have been used in agriculture, electronics, superconductors, nuclear medicine, automobile industry, special inks – as those used in radar invisible airplanes, X-ray screens, high intensity mercury vapour light bulbs, neutron scintilators, charged-particle detectors and optical memory reading systems (Maestro & Huguenin, 1995; Nagaosa & Binghua, 1997; Sánchez et al., 1999)."

Jan 1, 2012

By G. Minhas, M. Pule, Y. Laffitte, M. c. McGurn, T. Tzanetakis, Peacey. J., R. Susilo

Titanium (Ti) metal production from titanium tetrachloride (TiCl4) using magnesium (Mg) as a reducing agent is the well-known Kroll process. A chloride route is used to avoid oxidation of the titanium sponge. The sponge is consolidated into ingots and can then be made into powder by melting and atomizing or by hydriding/dehydriding. Attempts at direct powder production have met with difficulties, including low Ti yield and the formation of very fine particles (particles between 25-100 µm are desired). This paper discusses two methods to produce Ti powder in a molten salt medium using magnesium powder as a starting material instead of a pool of molten magnesium. The first method is a direct reduction of gaseous TiCl4 injected in the melt with the magnesium powder in suspension in the molten salt. The second method is a two stage TiCl4 reduction reaction where recycled Ti was used to form titanium dichloride (TiCl2) in the first stage followed by addition of magnesium powder into molten salt in the second stage. A correlation between Ti yield and processing variables such as TiCl4 to Mg ratio, Mg particle size, TiCl2 concentration in the melt, and reaction temperature was studied. The Ti powder formed was also analyzed for particle size distribution. Despite challenges and difficulties encountered, this paper shows some promising results which could provide guidance to others working on direct Ti powder production.

Jan 1, 2015

By A. Vervoort, A. Govaerts

Geostatistical concepts are often difficult for students to understand, even those with a strong mathematical background. One of the main problems is the link between the variation of the parameter value in space or time and the calculated experimental semivariogram. Another challenge is differentiating between directional and omnidirectional semivariograms and their interpretation. For these reasons, interactive tools were developed based on the free public domain software R. The use of these interactive tools is limited to educational situations only (i.e., to visualize basic concepts). The interactive modules can be accessed at www.bwk.kuleuven.be/geostatistics.

Jan 1, 2014

By M. Bustin, A. Hosseinian, G. Preisig

Hydraulic fracturing and hydraulic shearing techniques are essential for the development of unconventional oil & gas and geothermal resources. Such techniques will also play a key role in the development of CO2 sequestration, and management of high stresses encountered with deep mining. However, the optimal design of hydraulic injections is often limited by continuum treatments of the rock mass without consideration of the influence of the natural fractures present. These may interact with the hydraulic fracture to promote offsets or arrest, or may cause the natural fractures to undergo shear and dilation. Given the limited access to the rock afforded by deep boreholes common to oil & gas and geothermal projects, advanced numerical modeling is critical for understanding key mechanisms and interactions. In this work, we first present a coupled hydromechanical distinct-element model focusing on the propagation of a hydraulic fracture. Normal and shear displacements arising from the generated hydraulic fractures are subsequently integrated into a fracture flow model for detailed analysis of specific flow behaviour and fracture permeability. For this, a scanned 3-D profile of a natural fracture is used to correlate surface roughness to dilation as a function of shearing. Fracture flow is computed at different time steps corresponding to different fracture propagation states and geometries. Modeling results indicate that the opening of a tensile hydraulic fracture is accompanied by millimetre-scale shear displacements associated with slip and wedging between adjacent blocks. This may leads to a mismatch between the upper and lower walls of the fracture if asperities are irregular and strong enough. However, fluid-induced tensile fractures have low Joint Roughness Coefficients (JRC), and associated millimetre-scale shear displacements are too small to ensure a significant offset of asperities that prevent a fully-elastic closure when the hydraulic fracture is depressurized. Injection of proppant is thus critical to keeping hydraulic fracture apertures open. Future work is planned that will see the models calibrated against field data including microseismic event locations, magnitudes and source mechanisms, tiltmeter deformations, stress change, and pore pressures.

Jan 1, 2015

By Du Xinfeng

The resource quantity of the low rank coalbed methane (CBM) accounts for 47% of the total resource quantity of CBM in China. Compared with the exploration and development of the high rank CBM in Qinshui Basin, China and the low rank CBM in Powder River Basin, USA and Albert Basin, Canada, the exploration and development of the low rank CBM are still in the initial test stage. In this paper, on the basis of analyzing the mining geological conditions such as that the Huanglong Jurassic Coalfield is largely situated in the hills and gullies zones, and the coal reservoir has the features such as the low metamorphic degree, large coal seam thickness, simple coal matrix texture, high permeability and small CBM content and so on, it discusses the key technologies such as the development pattern of CBM, well location arrangement, drilling and well completion technology and fracturing technology and so on. It indicates that the underbalanced drilling and the cavity well completion based on the reservoir protection will be the development directions of the CBM development technology in this area.

Aug 1, 2013

By J. Coffin, M. Muinonen, D. Fragomeni, R. Multani, C. Deredin

"Rejection of pyrrhotite from pentlandite is of critical importance to the economics of nickel concentrate production and the main goal of the Strathcona milling operations. A joint team of XPS, Glencore Technology and Strathcona Mill personnel executed a comprehensive program of work to develop and implement strategies for increased Po rejection with focus on challenging ores containing high feed Po/Pn ratios (> 7) and significant hexagonal Po content (> 40% of total Po). This paper describes the team results including minerology, bench-scale flotation tests, and plant validation tests and modeling that have defined the path forward to improving the metallurgical performance and economics of the mill operation. Techniques to quantify hexagonal and monoclinic pyrrhotites were developed at XPS to assess the differences in their metallurgical behavior since their flotation responses are quite different. Mineralogical tools including QEMScan were extensively used to determine mineral liberation, associations, optimum grind size, and nickel deportment into pentlandite, pyrrhotite and non-sulphide gangue. Several reagents/strategies were evaluated during bench-scale flotation testing to significantly increase Po rejection. A significant shift in the Po-Pn selectivity and grade recovery curves was achieved using several strategies including the use of DETA and sodium metabisulfite, and regrind of the rougher concentrate and rougher cleaner/rougher tails.INTRODUCTION The Strathcona Mill is owned and operated by Glencore Nickel – Sudbury Integrated Nickel Operations and has been processing Ni-Cu ores from the Sudbury Basin since 1968 (valuable sulphides: pentlandite (Pn) – (Ni,Fe)9S8 and chalcopyrite (Cp) – CuFeS2). Currently Strathcona Mill receives ore mined from two main sources in the Sudbury area and produces two concentrate streams – a nickel-copper concentrate that is shipped to the Sudbury Smelter and a copper concentrate that is sent to the Fonderie Horne (Glencore Copper, Rouyn-Noranda). The general flowsheet currently used at Strathcona is displayed in Figure 1. It is highlighted by separate feed circuits for regular grade Ni ores and high grade copper ores. The copper circuit has a preflotation stage prior to a rougher-scavenger stage, a copper-nickel separation circuit, and a pyrrhotite (Po) rejection circuit."

Jan 1, 2018

By Mark Sherman, M. Dennis, Raj Rajamani

"The two Alumbrera 36ft (10.97m)dia. SAG mills were sized, using the FDW ""Grindpower 'I program, to treat an average of 1852 tph each. This paper describes how modelling of the shell lifter design, using the Millsoft program, identified milling inefficiencies caused by poor charge motion. This explained the ""as built"" circuit's inability to achieve the throughput rates predcted by the circuit's designer. Use of the Millsoft program to design a new, dramatically different lifter configuration, in conjunction with a different approach to variable speed drive utilization, has resulted in an improved charge motion and a 30% increase in hard ore milling rates. The new lifter design has allowed the designer's predicted average throughput rates to be achieved.IntroductionThe Alumbrera project grinding circuit consists of two 36ft dia. X 17ft EGL, 13 500 kW, variable speed, gearless drive SAG mills coupled to four 20ft dia. X 30ft EGL, 6 000 kW fixed speed, gear driven, ball mills. The circuit is configured as two identical grinding aisles, each consisting of one SAG mill and two ball mills. No pebble crushing circuit was installed due to the expected absence of a critical size fraction in the first years of production. However, the grinding circuit layout does incorporate space for a pebble crushing retrofit. At present, only about 5% - 10% of the new mill feed reports as trommel oversize and is recycled back to each SAG mill using a water cannon.The circuit was designed to be ball mill limited and to treat the four major Alumbrera ore types at rates varying between 68 000 tpd, and 89 750 tpd, depending on ore hardness. Average throughput rate, and hence nominal design rate, for the grinding circuit was 80 000 tpd (1 852tph per line at 90% availability)."

Jan 1, 1999

By M. A. Perras, H. A. Kasani, G. Walton

The development of an underground repository for the storage of spent nuclear fuel relies on a multi-barrier system to isolate the used fuel from the environment – ultimately, the biosphere. These barriers include engineered copper and steal canisters, dense bentonite, and the natural rock as well. In order to reduce the potential flow pathway along the excavation induced damage zone, various slots perpendicular to the excavation axis have been proposed. These slots are called cut-off seals and generally are filled with bentonite as it has high swelling potential and very low permeability. Many different geometries have been proposed, but clear guidelines on the selection of the optimum geometry have yet to be developed. In order to assess the optimum geometry, three shapes have been selected for this numerical study, including a trapezoid, a triangle, and a thin rectangular slot. The cut-offs were modelled for a conceptual shaft constructed in the Queenston Formation from Ontario over a stress to strength ratio that has been found at many underground research laboratories. It was found that the excavation of a triangular and thin slot cut-off had the smallest increase in the damage as quantified based on the extensile volumetric strain within the plastic yield zone. Both shapes showed an increase in the damaged zone by 13 cm at a stress to strength ratio of 2.75. The trapezoidal cut-off damage zone increased by 20 cm at the same stress to strength ratio. Further study is required to better define the optimum cut-off shape for wider variety of conditions and other geological formations.

Jan 1, 2020

One Data Set for the Lifecycle Complete data captured at the logging stage benefits the entire life cycle Exploration Technical Studies Production and Milling Visible Light Spectrum Hyperspectral, put simply, is the interaction of light with matter based on the nature and chemical structure of the specimen. SpectrumWe develop the library to match the liberation size fraction Analyses every 1mm2 1 meter of NQ core = 35 000 analysis data Crystal size detection : 0.1 micron

May 1, 2013

By M. Mai Manga, M. Renaud, A. Faucher, C. Bazin

ABSTRACT Grinding circuits are operated in the presence of disturbances resulting from ore changes and equipment malfunctions, such as hydrocyclone overloading, worn or partly plugged apexes, surging, and internal liner detachment that may cause a loss of classification performance. Metal recovery losses in downstream leaching or flotation circuits justify the development of methods for rapid detection of hydrocyclone malfunction. Two methods are presented in this paper. The first method uses measurements from sensors available in a grinding circuit and the second uses vibration sensors installed on the individual hydrocyclones of a nest.

Jan 1, 2011

By H. Itou

A mechanism of scorodite formation at ambient pressure was investigated using transmission electron microscopy (TEM). Several types of iron arsenate were obtained from Fe/As solutions (Fe/As = 1.0 and 1.5) at pH values of 1.0, 1.25 and 1.5 at 95°C. Amorphous FeAsO4.xH2O was precipitated from solutions having a higher mole ratio of Fe/As at pH l.5, even after 9 hours. A few micron sized particles were observed by SEM, but these proved to be agglomerates of 10-50 nm amorphous FeAsarxH2O particles when observed by TEM. This means that supersaturation of the solution causes the acceleration of nucleation of iron arsenate hydrate. Crystalline scorodite was obtained from a solution in which the Fe/As mole ratio was unity, at pH l.0 and pH 1.5, after 3 hours. Almond-type crystalline scorodite particles were observed by TEM and most of them showed high crystallinity. The addition of scorodite seed material enhanced the crystallization. Amorphous FeAsO4.xH2O, however, was observed at the surface of the seeds during the early stages of precipitation. It is postulated that crystalline scorodite is not directly precipitated even on crystalline scorodite seeds, but requires a certain time to crystallize on the seed material.

Jan 1, 2006

By G. L. Palmer

"In 1986, anomalous sampling results for heavy minerals were obtained at various sites in Namaqualand on the west coast of the Cape Province. Drilling in 1987 at Graauwduinen penetrated up to 35 meters of heavy mineral-bearing Tertiary sands which extend several kilometers inland from the coast. The heavy mineral suite includes ilmenite, rutile, leucoxene, zircon and monazite, along with gamet, pyroxene and amphibole. Three deposits are recognized, two of which comprise the resource to be mined by Namakwa Sands Limited, a recently formed Anglo American Corporation subsidiary company.Mineable reserves in excess of 500 million tonnes have been delineated, sufficient to sustain mining for over 35 years at projected production rates. During the feasibility study, on-site investigations included test mining at various sites to assess rnineability and to provide material for metallurgical testing in a pilot plant located at the site. llmenite produced at the mine will be smelted at a new facility to be built at Saldanha Bay. Saleable products comprise titania-rich slag, pig iron, zircon and rutile.During the exploration phase, company environmental guidelines were established and monitored. The feasibility study incorporated a Class 1 Environmental Impact Report, the contents of which were made public following the principles of the Integrated Environmental Management legislation."

Jan 1, 1994