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By Daniel J. Schulze

Abstract-Eclogite is an important source of diamond in the upper mantle, but is more localized than peridotite. Using eclogitic minerals in kimberlite and diamond exploration is also more problematic than using the well-known peridotite-derived indicator minerals Cr-pyrope and magnesiochromite. The problems include color similarities between orange garnets from eclogites, Cr-poor megacrysts, and crustal garnets, chemical similarities with Cr-poor megacryst suite garnets (specifically elevated Na2O contents), and low abundance of eclogite garnet xenocrysts in most known kimberlites. Chemical screens must be used carefully to distinguish between varieties of orange garnets in exploration samples. For example, most orange garnets of crustal origin have >22 wt% FeO, with mantle eclogite garnets having lower values. Na2O-bearing garnets from the Cr-poor megacryst suite can be distinguished from Na2O-bearing garnets from diamondiferous eclogites by the elevated TiO2 contents of the former. The low abundance of eclogite garnet xenocrysts in kimberlites worldwide, however, may dictate that use of eclogite garnets in diamond exploration in most cases be restricted to advanced stages of kimberlite exploration and evaluation of kimberlite diamond potential. Crpyropes, Mg-ilmenites and Cr-rich chromites are more useful than eclogitic garnets in most stages of diamond exploration. If orange garnet xenocrysts are sought in a kimberlite exploration program, those from the Cr-poor megacryst suite will be more useful than eclogite derived garnets, due to the typical great abundance of the former, although they carry no information of the diamond potential of the host kimberlite.

Jan 1, 1997

By Daniel J. Schulze

Eclogite is an important source of diamond in the upper mantle, but is more localized than peridotite. Using eclogitic minerals in kimberlite and diamond exploration is also more problematic than using the well-known peridotite-derived indicator minerals Cr-pyrope and magnesio-chromite. The problems include color similarities between orange garnets from eclogites, Cr-poor megacrysts, and crustal garnets, chemical similarities with Cr-poor megacryst suite garnets (speci?cally elevated Na2O contents), and low abundance of eclogite garnet xenocrysts in most known kimberlites. Chemical screens must be used carefully to distinguish between varieties of orange garnetsin exploration samples. For example, most orange garnets of crustal origin have >22 wt% FeO, with mantle eclogite garnets having lower values. Na2O-bearing garnets from the Cr-poor megacryst suite can be distinguished from Na2O-bearing garnets from diamondiferous eclogites by the elevated TiO2contents of the former. The low abundance of eclogite garnet xenocrysts in kimberlites worldwide, however, may dictate that use of eclogite garnets in diamond exploration in most cases be restricted to advanced stages of kimberlite exploration and evaluation of kimberlite diamond potential. Cr-pyropes, Mg-ilmenites and Cr-rich chromites are more useful than eclogitic garnets in most stages of diamond exploration. If orange garnet xenocrysts are sought in a kimberlite exploration program, those from the Cr-poor megacryst suite will be more useful than eclogite derived garnets, due to the typical great abundance of the former, although they carry no information of the diamond potential of the host kimberlite.

Jan 1, 1997

By Herbert D. Drechsler, James B. Stephenson

"AbstractThe paper identifies the major components of price change which affect the determination of the internal rate of return of a mining project. It illustrates several price indexes which may be used to measure general price increases, identifying techniques which might incorporate them into mine valuation procedures. The ""hurdle rate"" for new investment is discussed.IntroductionDECISIONS regarding the value of an orebody and whether or when to mine an orebody are based on an estimate of the cash flows which would be associated with its exploitation. These pro-forma cash flows represent cash in or out of a possible mineable deposit and include exploration and construction costs, sales revenues, operating expenses, taxes, debt borrowings, interest and debt repayment. It has long been recognized that when combining the cash flows occurring over the life of the mine, dollars received or paid out early have greater value than those received or paid out later. This time value of money has been incorporated into mine evaluation calculations through the use of present-value or discounting techniques. Another factor affecting mine valuation, inflation, is not accounted for by valuation techniques now in use. In recent years, price changes have become more volatile. In the past, price change could easily be ignored when evaluating potential mines. Today, the combination of larger investments and greater price volatility leads to great concern about the effects of price change on mine valuation."

Jan 1, 1977

By J. Asfahani

"The inverse slope method (ISM) was applied to reinterpret vertical electrical soundings (VES) data from pits at the Al-Sharquieh phosphate mine, in order to demonstrate applicability and suitability of the ISM for interpreting VES data from sedimentary phosphatic environments. The ISM overcomes limitations of the curve matching method and the complexity of lithological sections. The ISM geo-electrical interpretation results correlated well with lithologies of the pits. This method characterized resistivity and thickness of the phosphatic layer, and identified favourable phosphate-prospecting areas using the newly developed thickness/depth parameter. The ISM is recommended for interpreting VES measurements in similar sedimentary phosphatic regions.RÉSUMÉ La méthode d’inversion de la pente (ISM) a été utilisée pour réinterpréter les données de sondages électriques verticaux (VES) effectués dans des puits de la mine de phosphate Al-Sharquieh, afin de démontrer l’applicabilité et la pertinence de cette méthode pour interpréter les données VES dans des environnements de sédimentation de phosphates. Cette méthode (ISM) surmonte les limitations de la méthode de comparaison de courbes et la complexité des sections lithologiques. Les résultats de l’interprétation géoélectrique ISM correspondaient bien aux lithologies des puits. Elle a permis de caractériser la résistivité et l’épaisseur de la couche phosphatique et d’identifier les secteurs favorables à la prospection pour le phosphate en utilisant le paramètre nouvellement développé épaisseur/profondeur. ISM est recommandée pour l’interprétation des mesures VES dans des régions semblables où se trouve du phosphate sédimentaire."

Jan 1, 2016

By F. Chiesa

The permanent mould process, which is a favoured process for producing premium quality aluminium casting, is rarely used to produce magnesium alloy parts. This may be attributed different factors such as: the reservation with which the automotive industry considers using magnesium in structural castings; also the relative hot shortness of most magnesium alloys when compared to aluminium A356/357 is another factor. A third reason stems from the fact that the "heat content" of magnesium is much less than that of aluminium, resulting in the difficulty, for a relatively slow process such as permanent mould (versus pressure die casting), to reach a mould dynamic equilibrium temperature sufficiently high to avoid premature freezing and misruns. The present work will address this problem by carrying out controlled cycling of a laboratory mould, poured with aluminium and magnesium alloys. The influence of insulation of the mould and artificial electric heating on the run-in mould temperature will be determined experimentally. A thermal model will be sought for these thermal devices that will allow to predict the thermal behaviour of moulds of different geometry before a single casting is poured. The model will be tested on an industrial casting in a workshop environment.

Jan 1, 2006

"The outlook for Eastern Canada is decreasing coal production over the next few years; however, a reappraisal of the long-term requirements and increased prices of coal could lead to a revitalizing of the industry. The market for Western coal is expanding and is expected to exceed 50 million tons per year in the metallurgical and thermal power fields. Western coal reserves are currently estimated at 119 billion tons. Technical developments in Eastern Canada include a shearer and gate-end support system to mechanically cut the stall and brushing at the tail-end of a longwall. In Western Canada, the most modern equipment is used in mining, beneficiating and shipping coal. Results to date on the underground hydraulic experiments exceed expectations. The importance of reclamation is recognized and plans have been made to restore and re-vegetate disturbed areas and mine dumps. In Eastern Canada, experiments were started to determine the feasibility of coal reclamation from mine dumps, including one dump that is on fire. The Mining Research Centre, Mines Branch, continued to conduct research work oriented toward solving Canadian mining problems The Western office of the Centre, opened in 1970, was set up primarily to study problems associated with a resurgent coal industry."

Jan 1, 1971

By W. G. Miller

An overall study was conducted to evaluate the properties and processes influencing the rate and magnitude of consolidation for oil sands fine tailings produced using different extraction processes. As part of this overall study, consolidation tests using slurry consolidometers were carried out for caustic and non-caustic fine tailings. The influence of a change in bitumen extraction process (caustic versus non-caustic) on consolidation properties, namely compressibility and hydraulic conductivity, was determined, as was the effect of adding a coagulant (calcium sulphate [CaSO4]) to caustic fine tailings. For fine tailings originating from two different oil sands ores (Ore A and Ore B), results were presented in terms of variation in average void ratio with time (settlement), void ratio with effective stress (compressibility), hydraulic conductivity with void ratio and coefficient of compressibility and hydraulic conductivity with sodium adsorption ratio. Findings indicated that chemical characteristics of fine tailings (water chemistry, degree of dispersion) do not have a significant impact on their compressibility behaviour and have only a small influence at high void ratio (low effective stress). The biggest advantage of non-caustic fine tailings and treating caustic fine tailings with coagulant is an increased initial settlement rate and slightly increased hydraulic conductivity at higher void ratios. Thereafter, compressibility and hydraulic conductivity is governed by effective stress.

Aug 1, 2010

By W. G. Miller, J. D. Scott, D. C. Sego

An overall study was conducted to evaluate the properties and processes influencing the rate and magnitude of consolidation for oil sands fine tailings produced using different extraction processes. As part of this overall study, consolidation tests using slurry consolidometers were carried out for caustic and non-caustic fine tailings. The influence of a change in bitumen extraction process (caustic versus non-caustic) on consolidation properties, namely compressibility and hydraulic conductivity, was determined, as was the effect of adding a coagulant (calcium sulphate [CaSO4]) to caustic fine tailings. For fine tailings originating from two different oil sands ores (Ore A and Ore B), results were presented in terms of variation in average void ratio with time (settlement), void ratio with effective stress (compressibility), hydraulic conductivity with void ratio and coefficient of compressibility and hydraulic conductivity with sodium adsorption ratio. Findings indicated that chemical characteristics of fine tailings (water chemistry, degree of dispersion) do not have a significant impact on their compressibility behaviour and have only a small influence at high void ratio (low effective stress). The biggest advantage of non-caustic fine tailings and treating caustic fine tailings with coagulant is an increased initial settlement rate and slightly increased hydraulic conductivity at higher void ratios. Thereafter, compressibility and hydraulic conductivity is governed by effective stress.

Jan 1, 2010

By Martin P. Raffield

Placer Domes? Campbell Mine, situated in northwestern Ontario, is undergoing an assessment of the efficiency of the operation which is necessitated by the low gold price and a reducing ore reserve grade. A decision has recently been taken to move away from a functional based departmental structure (underground, engineering, geology, etc.) towards a team-based system where crews, engineers, geologists and supervisors are responsible for the planning and operation of a particular area of the mine. The objective is to improve communication and understanding of the goals and achievements and to ensure a forum is available for the generation of ideas. It is intended to increase the accountability and decision-making ability of the teams in an effort to achieve the mines? safety and production targets. This paper presents a critical review of the progress of this organisational change process and its successes and failures at the time of writing.

Oct 1, 2001

By V. J. Southey

HOLLINGER mining operations have required development by 24 vertical shafts having a total length of 28,160 feet. Seventeen of these are sunk from surface and seven are interior shafts. Four surface shafts and three interior shafts are now active and, excepting the recently completed new main ore-hoisting shaft, the remainder are either abandoned, or are used for passes or for ventilation. The new shaft bottoms 60 feet below the 3,050 level, but there is much work to be done before it is placed in service. The term 'shaft practice' is intended to include shaft construction and a general treatment o typical equipment. It is a large subject for an organization the size of Hollinger and this paper is intended only to present the salient features. The writer wishes to thank the management for permission to publish this information and to acknowledge the advice and criticism o A. G. Irving, chief engineer, and the willing co-operation of other members of the Hollinger staff.

Jan 1, 1939

By M. Tadayonsaidi

The effect of alloying elements on the mechanical properties and thermal expansion of 336 casting alloy usually used as piston alloy which has low thermal expansion and very good high-temperature mechanical properties and good wear resistance was investigated. The mechanical properties and thermal expansion characteristic of samples with different combination of alloying elements, which enhance to reduce the cost of products, have been studies, The results show remarkable increase in the mechanical properties with increasing the amount of Cu and Mg, while are reduced with increasing amount of Ni, On the other hand, the use of eutectic aluminum alloy as 336 alloy with higher percent of Cu and Mg and lower percent of Ni are recommended for industry, due to economical viewpoint and satisfactory properties.

Jan 1, 2005

By W. van der Merwe

ABSTRACT With the gold industry processing more complex ores, the online measurement and control of cyanide addition to the gold leaching circuit has become more critical. This paper compares the two commonly employed ‘free’ cyanide online analysis methods (amperometric and potentiometric endpoint silver nitrate titration) with the rhodanine endpoint silver nitrate titration and ion selective electrode methods common at site laboratories. Measurement differences between these methods are presented and discussed for cyanide solutions containing copper and zinc with varying cyanide to metal ion ratios. The resulting cyanide available to leach gold is also compared using these measurement techniques.

Jan 1, 2013

By J. Zollinger, J. R. Kennedy, J. H. Park, D. Daloz

"In order to improve the properties of cast Ti-Al alloys to replace Ni-based superalloys past the low pressure stages of aircraft engines investigations into inoculation for grain refinement were carried out. Previous work showed isomorphic self-inoculation using Ti-Al-Nb particles was effective for grain refinement, however the relatively fast diffusion of Nb in Ti-Al make it difficult to observe the mechanism of nucleation. An alternative alloy was developed in the Ti-Ta system for isomorphic self-inoculation, maximizing the Ta content to improve the particles survivability in the melt. The powder processing produced comparatively small inoculant particles which dissolved, however larger particles were seen to survive solidification. The density difference between the inoculant particles and melt resulted in an inhomogeneous mixing of the particles and the melt with larger particles found near the outer edges of the ingots. Variations on particle size and interaction time between the inoculants and the melt resulted in the Ti-Ta inoculant reducing the as-cast equiaxed grain size by a factor of two compared to non-inoculated samples as well as increasing the equiaxed fraction in the ingot.INTRODUCTION Lightweight metals are of particular interest in aerospace applications. The hot sections of turbines are dominated by blades made of nickel based superalloys. Recently the GEnx turbine introduced TiAl blades in the last low pressure stage of the turbine to reduce weight and improve fuel efficiency (Kim & Dimiduk, 1991). In order to carry these benefits deeper into the turbine the high temperature (>800oC) properties of the alloys must be improved. Current grain refinement methods to improve properties rely on boron additions which may not be applicable for all blades as brittle precipitates may be formed during processing (McCullough, Levi, Mehrabian, & Hyman, 1991). A novel grain refinement process was previously introduced called “isomorphic self-inoculation” using Ti-Al-Nb particles to successfully grain refine TiAl (Kennedy, Zollinger, Bouzy, & Daloz, 2016). In order to better understand the mechanism of this process an investigation was carried out using the same process but with a Ti-Ta alloy which is more stable in the TiAl melt than the Ti-Al-Nb."

Jan 1, 2017

By Sangjian Zhang, Zhu Xiao, Lairong Xiao, Rushi Chen, Mei Fang, Zhou Li

The copper-graphite metal matrix composites were fabricated by two different production methods: directly sintering with copper and graphite (Cu-Gr composite), and in-situ sintering with cuprous copper and graphite (Cu2O-Gr composite). During the in-situ reaction sintering, a redox reaction occurs at the interface of the Cu2O particles and Gr particles, resulting in the improved physical and mechanical properties of Cu2O-Gr composites. Compared with Cu-Gr composite, Cu2O-Gr composite has a higher compression strength at any given graphite content due to the improved interface bonding and uniformly distributed fine graphite particles in the matrix. Increasing graphite content decreases the mechanical properties of the copper-graphite composites. The compression strength of Cu2O-Gr composite is 50-100 MPa higher than that of Cu-Gr composite. INTRODUCTION Copper-graphite composites have been widely used in industry due to their low density, relatively high strength and hardness, good thermal and electrical conductivity, arc ablation resistance and self- lubrication ability (Grandin & Wiklund, 2018; Han & Xu, 1999; Huang et al., 2017). Electric sliding contact friction pair in the high-speed railway system and motor brush in electric contact components have a very high demand on electrical conductivity and self-lubrication ability of materials. The electric devices need to bear both mechanical load and high electric current. Copper-graphite composites with good mechanical, electric and self-lubrication properties are the best candidates for application in multifunctional electric sliding contact frication components. The relative sliding speed of friction pair is developing towards 100 m/s or even faster, which can withstand the electric flow of more than 800 A, and it is often accompanied with vibration and impact (Guo & Ding, 2008). Conventional wear-resistant materials can no longer meet the current requirements and this promotes the development of copper- graphite composites with excellent comprehensive properties (Ding, Chen, Zhu, Zhang, & Zhou, 2009; Yasar, Canakci, & Arslan, 2007). There are many ways to fabricate copper-graphite composites, mainly including powder metallurgy method, liquid immersion infiltration method, rapid sintering method and electrodeposition method (Kalin & Poljanec, 2018; Kim, Lee, & Han, 2014; Liu et al., 2018; Wang et al., 2018). Each method has its own advantages and disadvantages, and the powder metallurgy method is the most commonly used one due to its simple process, high economic benefit, and industrial production applicability. The common steps of the powder metallurgy method are as follows (Samal, Parihar, & Chaira, 2013): firstly mixing the copper (copper alloy) powders and graphite with a certain ratio, following by die-forming, and then sintering at the high temperature with or without pressure. The advantage of copper-graphite composites is that the graphite distributed in the copper matrix uniformly and it can form a carbon diaphragm preventing the wear of the composite (Fu & He, 2010). However, the bonding strength of the interface between the copper matrix and the graphite is relative low as the combination between them is mechanical interlocking but not metallurgical bonding (Ma et al., 2008). It is meaningful to develop new fabrication technology of copper-graphite composites with better interface bonding, which could provide guidance for the design of copper-graphite composites with excellent comprehensive properties.

Jan 1, 2019

By R. H. Chambers, L. Alderman

"The paper is introduced by an examination of the factors which have led to the present world-wide interest in charging preheated coal to coke ovens. Various possible methods of preheating and charging the coal are considered and reasons are given for the adoption of the methods chosen. The design of the pilot preheating plant for the British Coke Research Association is discussed and its influence on the design of the commercial units for the South African Iron and Steel Corporation's plant at Pretoria and the British Steel Corporation's plant at Beighton are explained. Operating procedures on the pilot plant are described, particularly with regard to the charging of the preheated coal. Design features of the commercial installations, engineered by Simon-Carves Ltd., are explained with emphasis on the built-in safety of the control system of the preheating plant, and the particular problems associated with the erection of such plants on working coke oven batteries. Commissioning and operating procedures are described and the problems associated with the integration of the preheating plant into the normal pushing schedule of the plant are discussed. Preliminary operating results with regard to the effect of preheating on coal throughput on the commercial plants and on the properties of the coke produced are given."

Jan 1, 1972

By M. J. Medd, G. A. Speirs

"This paper describes the simultaneous sinking and equipping of a 4.9 m diameter concrete-lined shaft to a projected depth of 1660 m. The shaft blast design utilizes the full face method using a parallel hole burn cut. Hydraulic drilling and a totally redesigned Cryderman-type mucking unit were integrated into the four deck sinking stage to provide for drilling, mucking, concreting and shaft steel equipping operations. A safety program was tailored and implemented specifically for this shaft sinking project.IntroductionIn July 1988, Falconbridge Limited commenced development of its Thayer Lindsley exploration site located some four km north of Sudbury on Regional Road 80.The first phase of this project was awarded to J .S. Redpath Mining Consultants Limited and the scope of work included the engineering and project management to construct a surface plant capable of supporting a shaft sinking and exploration program for potential future mine development. This initial phase of the project was completed on schedule and under budget on December 23, 1988, and is the subject of an independent paper.In November 1988, J.S. Redpath Limited was awarded the shaft sinking and exploration phase of this project. The scope of work consisted of sinking and equipping a 4.9 m diameter shaft to a depth of 1660 m and carrying out the development and diamond drilling on two levels. This work was scheduled to be completed by November 1991.The T .L. Exploration Project is located toward the eastern end of the south range of the Sudbury basin, north of Sudbury. Figure 1 details the projected mining area and the shaft location on the geological complex. Figure 2 is a section showing the exploration shaft that is located in the Norite. Two levels will be developed from this shaft, on the 1310m and 1588 m levels, to provide access for further geological examination of the ore bodies."

Jan 1, 1991

By Jin Liu, Torstein A. Utigard

At its Copper Cliff Smelter, Vale Inco Limited processes a bulk copper-nickel concentrate in two Inco oxygen flash furnaces. Coke supplies a minor proportion of the process heat requirements, limiting the flash furnace matte grade to the target 45% CuNiCo. Coke addition to the furnace offers a potential means of establishing a reducing barrier on the surface of the molten bath. Such a practice would be conducive to producing sulfur deficient (partially metallized) matte. At the same iron content, the iron activity of sulfur deficient matte is higher than that of regular matte. A supernatant coke barrier could, therefore, be expected to lead to higher nickel and cobalt recoveries, reduction or even elimination of magnetite furnace bottom build-up and increased sulfur elimination as SO2 in the flash furnace. Extensive experiments were conducted in a miniplant flash furnace to investigate the effect on process metallurgy of the suggested modified scheme. The introduction and description of the experimental set up were given in Part 1 of this paper and an early paper published in Yazawa symposium1 together with the results and some in depth discussion on metallurgy. This paper intends to discuss the kinetics of the miniplant flash furnace testwork.

Jan 1, 2015

By C. H. G. Bushell, G. Brown, C. J. Krauss

1N FLOTATION, copper sulphate is used universally for the activation of sphalerite and marmatite and, to some extent, for the activation of other minerals. The copper activated surface readily adsorbs standard collectors such as the xanthates and dialkyl dithiophosphates whereas untreated zir~ sulphide does not. With the host of reagents available, making a mineral float is seldom difficult. The problem is to achieve selective flotation. In zinc flotation, the great value of copper sulphate results from its ability to activate zinc sulphide preferentially to gangue minerals. At the Sullivan Concentrator of The Consolidated Mining and Smelting Company of Canada Limited, the most abundant gangue mineral in the lead-zinc ore is pyrrhotite, and the zinc mineral is marmatite of somewhat variable zinc to iron ratio. For this Cominco study, selectivity between marmatite and pyrrhotite was therefore the most interesting aspect of copper sulphate activation.

Jan 1, 1961

By Yuanming Pan, Brett Rogers, Baoquan Hu, Gary Yeo, Christine Austman

The nature and distribution of radiation-induced defects (RIDs) in quartz from the Maw Zone, a yttrium- and rare-earth-element-enriched sandstone breccia complex exhibiting intense hydrothermal alteration, have been investigated by electron paramagnetic resonance (EPR) spectroscopy. EPR spectra show that detrital quartz in sandstone, from five diamond drill holes intersecting the Maw Zone and one above the crest of the so-called Quartzite Ridge, contain only background-level RIDs, indicating that Ubearing fluids were absent in this area. However, close to the sandstone-basement unconformity, in hole WR-194 immediately west of the Quartzite Ridge, the concentration of RIDs in detrital quartz is significantly above background but at least an order of magnitude lower than those at the Key Lake and McArthur River deposits. Widespread drusy quartz at the Maw Zone, which signifies intense hydrothermal alteration, is associated with hematite-, sulfide- and carbonate-bearing mineral assemblages, which exhibit complex crosscutting relationships. EPR spectra of drusy quartz in all three types of mineral assemblages are low in RIDs as well, supporting the EPR evidence that fluids at the Maw Zone did not carry significant U. These EPR results suggest that, in spite of intense hydrothermal alteration and favorable structural geology, the Maw Zone is unlikely to host any significant U mineralization. Moreover, this study shows that the EPR technique is potentially a useful exploration tool, capable of determining whether individual alteration zones in the Athabasca Basin were associated with U-bearing fluids or not.

Jan 1, 2013

By C. M. Diaz, S. W. Marcuson

In the late 19th century, the discovery of rich nickel-copper sulfide ore bodies in Sudbury and the need for tonnage quantities of the metal to be used in nickel steel armor provided the foundation for establishing the Canadian nickel industry. For almost 50 years, International Nickel was the key player. In 1930, Falconbridge Nickel entered the field. These two companies remain the key Canadian nickel producers. This paper discusses the factors that have influenced the evolution of nickel smelting processes. The initial Sudbury ore smelting and nickel copper separation technologies were imported from abroad. It was only in 1937 that International Nickel established a process research laboratory in Copper Cliff The explosive post WW II industrial development created a strong demand for a broader variety of nickel products. For both International Nickel and Falconbridge, R&D became an essential business tool to succeed in the new market scenery. In the last few decades, new technologies were developed and commercialized to respond to the raising cost of energy, society pressing environmental concerns, the advent of nickel laterites as an important source of new metal, the incorporation of new nickel producers to the market, and, therefore, the need to increase productivity. Canada thus became an important exporter of technology. In this paper, the authors review this history with the objective of highlighting the forces that have triggered the most important changes in Canadian nickel smelting.

Jan 1, 2005