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By J. R. Lewis, J. H. Hamilton, V. D. Hanson, K. W. Heinlein, J. M.194-000-000-006 Vonfeld, J. P. Denny

TWO overfeed drum-type separators using a suspension of magnetite in water as the separating medium have been installed in the Champion NO. 1 preparation plant of the Pittsburgh Coal Co., Division of the Pittsburgh Consolidation Coal Company. A simplified flow diagram of the Champion No. 1 coarse coal circuit is shown in Fig. 1. A railroad car rotary dump, capable of handling 20 cars per hr, discharges the coal into a hopper. Coal is fed from the hopper of the rotary dump to a 60-in. belt conveyor by two reciprocating pan-type feeders. The belt conveyor feeds the run of mine coal onto the main raw coal screen. The first deck is fitted with 3 in. round hole perforated plate which removes the 3x0-in. coal. The second deck of the screen is equipped with 6-in. lip screens which separate the remaining coal into +6 in. and 6x3 in. The +6 in. coal is transferred to a shaking picking table and then discharged onto the loading boom. The 6x3-in. coal is fed to the No. 2 dense medium vessel for cleaning. The clean coal from this unit flows to a vibrating screen where the medium is removed and the coal sized into 6x4 in. and 4x3 in. The 6x4-in. coal is transferred to the loading booms and the 4x3-in. is conveyed to the clean coal classifying screens to remove degradation. The 3x0-in. raw coal is blended in a system composed of three storage bins having a total capacity of 400 tons. From these bins the coal is fed onto a 48-in. flight conveyor by three reciprocating feeders. This flight conveyor delivers the coal to the Rheo plant. The 3x0-in. coal is then cleaned in two 48-in. Rheolaveur launders each equipped with two Rheo boxes. The first set of boxes removes a primary refuse and the second set produces a middling product which is recirculated in the launders. The cleaned coal and water overflows from the primary launders to two sizing and dewatering shaker screens where the water and — -in. coal are removed for further cleaning in the Rheo fine coal plant. The 3x3h-in. clean coal is combined with the 4x3-in. coal from the No. 2 vessel, sized into 4x2 in., 2x1 34 in., and 1'/4x in., then sent to the loading booms. The 3x0-in. refuse from the primary launders is normally fed to the No. 1 dense medium circuit, but any portion or all of this material can, as an alternate, be processed in the Rheo rewash launder. The primary refuse when fed to the dense medium circuit is screened into YSXO which is cleaned in the fine coal plant and 3x for cleaning in the No. 1 vessel. The clean coal from this vessel is passed over a vibrating drainage and rinse screen, then sluiced to the rewash sizing shaker where it is dewatered and sized for loading. The installation of a pilot plant separating vessel using a suspension of magnetite in water was pro-

Jan 1, 1953

By J. H. Hamilton, J. R. Lewis, K. W. Heinlein, V. D. Hanson, J. M. 194-000-000-006 Vonfeld, J. P. Denny

TWO overfeed drum-type separators using a suspension of magnetite in water as the separating medium have been installed in the Champion NO. 1 preparation plant of the Pittsburgh Coal Co., Division of the Pittsburgh Consolidation Coal Company. A simplified flow diagram of the Champion No. 1 coarse coal circuit is shown in Fig. 1. A railroad car rotary dump, capable of handling 20 cars per hr, discharges the coal into a hopper. Coal is fed from the hopper of the rotary dump to a 60-in. belt conveyor by two reciprocating pan-type feeders. The belt conveyor feeds the run of mine coal onto the main raw coal screen. The first deck is fitted with 3 in. round hole perforated plate which removes the 3x0-in. coal. The second deck of the screen is equipped with 6-in. lip screens which separate the remaining coal into +6 in. and 6x3 in. The +6 in. coal is transferred to a shaking picking table and then discharged onto the loading boom. The 6x3-in. coal is fed to the No. 2 dense medium vessel for cleaning. The clean coal from this unit flows to a vibrating screen where the medium is removed and the coal sized into 6x4 in. and 4x3 in. The 6x4-in. coal is transferred to the loading booms and the 4x3-in. is conveyed to the clean coal classifying screens to remove degradation. The 3x0-in. raw coal is blended in a system composed of three storage bins having a total capacity of 400 tons. From these bins the coal is fed onto a 48-in. flight conveyor by three reciprocating feeders. This flight conveyor delivers the coal to the Rheo plant. The 3x0-in. coal is then cleaned in two 48-in. Rheolaveur launders each equipped with two Rheo boxes. The first set of boxes removes a primary refuse and the second set produces a middling product which is recirculated in the launders. The cleaned coal and water overflows from the primary launders to two sizing and dewatering shaker screens where the water and — -in. coal are removed for further cleaning in the Rheo fine coal plant. The 3x3h-in. clean coal is combined with the 4x3-in. coal from the No. 2 vessel, sized into 4x2 in., 2x1 34 in., and 1'/4x in., then sent to the loading booms. The 3x0-in. refuse from the primary launders is normally fed to the No. 1 dense medium circuit, but any portion or all of this material can, as an alternate, be processed in the Rheo rewash launder. The primary refuse when fed to the dense medium circuit is screened into YSXO which is cleaned in the fine coal plant and 3x for cleaning in the No. 1 vessel. The clean coal from this vessel is passed over a vibrating drainage and rinse screen, then sluiced to the rewash sizing shaker where it is dewatered and sized for loading. The installation of a pilot plant separating vessel using a suspension of magnetite in water was pro-

Jan 1, 1953

By S. L. Miller

The development of a pilot gold geostatistical ore reserve system proved that geostatistical methods worked well for the routine production of annual ore reserves on gold mines of the Gold Fields of South Africa (GFSA) group, and that the techniques could also be practically implemented, understood and accepted by Survey Department personnel. Many side benefits of the pilot system became apparent, and a variety of useful management information was provided by manipulating the data values that were already captured. It was decided that it was a priority computing project to develop a standard production system (GORS) for routine use by all the GFSA gold mines. Experience with the pilot system enabled detailed functional specifications for GORS to be laid down. These, together with group computing policy determined the terms of reference and constraints for the GORS development. System design could not be finalized until new and appropriate mainframe database software and graphics workstation equipment and software had been found. With these in place the basic system was structured to take best ad- vantage of the interactive features of the workstation, the number-crunching power of the mainframe and the flexibility offered by a relational database and associated 4GL tools. Application sub-systems were developed for data capture, statistical applications, geostatistical calculations, contour plotting and graphical queries. GORS is being introduced to the mines in a phased manner with suitable documentation, training and support structures to enable it to be routinely and effectively used on a day-to-day basis by all group gold mines.

Jan 1, 1987

By S. K. Mukherjee, A. W. Laurito, M. M. Singh, N. I. Jayaraman

This paper describes the application of foam to control respirable dust in a double-drum longwall mining section. The feasibility of injecting an adequate quantity of foam through the shearer drum was initially established in the laboratory. Thereafter, underground testing of the foam system to determine its effectiveness on an active operating longwall was conducted in a mine in West Virginia. The foam system proved superior to the water spray system. The details of the laboratory and field investigations, the results obtained, and the degree of acceptance of this system by the mining company are discussed in this paper.

Jan 1, 1987

By C. R. Copeland

Airborne dust emission standards are receiving growing attention. This trend is motivated by significant health studies that have shown adverse health effects due to exposure to dust. Currently, the air quality standards are not specific to particles in the nanoparticulate range (<1,000 nm). However, as our understanding of health related matters increases, it is very likely that nanoparticulate standards will be adopted. It was previously believed that typical comminution and material-handling practices could not result in airborne nanoparticulates. However, experimental studies using air monitoring and SEM have verified the presence of nanoparticulates in the air as a result of comminution and material handling. This means that emerging nanoparticulate air quality standards are a real possibility for industrial operations. With this emerging problem facing the minerals industry, effective suppression methods for nanoparticulates should be explored. Systematic studies have indicated that nanoparticulates from silica can be suppressed utilizing hygroscopic reagents such as calcium chloride. This reagent was as much as 93% more effective than water in suppressing silica nanoparticulates.

Jan 1, 2007

By Dong-kil Lee

Field tests have been conducted to investigate the characteristics of flow and physical chemistry of acid mine drainage(AMD) in the Hwangji-Yuchang settling pond in south Korea. pH and ferrous concentration of AMD flowed in the settling pond is 6.79 and 25.5 mg/l, respectively. As a results, we found that the ferrous oxidation reacted strongly around the inlet of the pond and the distributions of physicochemical properties is depended on flow characteristics and ferrous oxidation rate of AMD.

May 1, 2011

By G. Bee, Z. Gavelan, R. Espinel, Y. Roditis, X. Ochoa

In August 1996 Barrick Gold Corporation acquired the Pierina property, an advanced stage exploration project, high in the Andean Cordillera of Peru and in November 1998, in a record time of just over two years, poured the first gold. After more than three years of a very successful operation at some of the lowest operating costs in the world, this presentation serves to briefly describe the project through design, construction and start-up and in particular to spotlight some of the challenges that have been overcome in valley heap leaching in a high rainfall, alpine setting.

Jan 1, 2002

By A. J. Langhammer

A. J. Langhammer.—That is rather asking a question of the wrong man. However, I will reply to the question from our point of view. There is a considerable amount of iron powder available but the properties vary over a wide range. Powder metallurgy has progressed to the stage where we recognize certain requirements in powdered iron, and what may be a good powdered iron for one application will not necessarily fit the picture for the next one. Further, I believe that there is room for great improvement in the properties of powdered iron. Also, that there is only a limited quantity of powdered iron available having certain specific properties in which we are at the moment interested. F. P. Peters.—May I have a word? With all possible respect to the contributions of the Chrysler Corporation (and they have been tremendous) to the war effort, I think it is easy to get from part of Mr. Langhammer&apos;s discussion a false impression of vaster possibilities than really exist. It would be well if in addition to Mr. Langhammer some other manufacturers of machine parts&apos; might tell us in the next few minutes some of the limitations they have found. For example, what is the maximum tensile strength that is being produced in a commercial part in production today? And what is the actual size limitation on bearings that are in operation and are standing up well? We should always bear in mind the fact—and I think Mr. Langhammer will agree with me— that quoting on a particular part does not necessarily mean placing it in production. In many cases it may be several months before the quotation is resolved and we know whether the part can be made. Let us open up this thing for a little free-for-all discussion of some of the ceilings that do exist in the design of machine parts made by powder metallurgy. The ceiling is not unlimited, and Mr. Langhsmmer will agree with that, 3 am sure. H. Hendriks.*—I do not think that there is so much limitation in the making of powder metallurgic manufactured parts as mentioned. Last year we had the problem of making dies for a special machine used in the manufacturing of slide fasteners. This part was wearing out very fast. It was very hard to make, it had to be hobbed out of a special steel and it was a difficult thing to manufacture in general. The tolerances were one half of one thousandth of one inch on all dimensions. We submitted this die to a manufacturer of powder-metal parts. He thought that it was impossible, but we were not as skeptical as he was and decided to try it anyway. The Canadian General Electric Carboloy Division, in Toronto, gave us then the design for the dies, which we made to their specifications. When the first part was delivered, we submitted it to our Inspection Department and its check showed that all the tolerances were right on the dot. They delivered I9 parts of exact specification, then they went off the beam; they could not keep to the tolerances. It took them a long time to get back again. We do not know what happened, but the main point I want to&apos; make is that if a problem is attacked in the right may, the dies are made right and corrected as to dimensions found out by experiment, I do not think that there is so much diffculty in making powder-metal parts to close tolerances.

Jan 1, 1945

Mining operations have been carried out at Mt. Lyell for the past century. Until the 1970&apos;s the location of the mines in relation to the surface topography has enabled the mines to drain their copious inflows of water by gravity. Deeper mining has forced the Company to undertake pumping of increasing inflows of water. A major pumping facility is being established near the base of the known ore reserves with a view to serving the future requirements of the mines. The system has a design capacity of 600 litres per second. Run of mine water will be treated in Vertical Flow Settlers to produce clear water and thickened mud, each of which will be disposed of separately. The clear water will be pumped by six 1000 kW conven- tional centrifugal pumps. The thickened mud will be removed by a Hydraulic Displacement System. The rising mains for both the mud and the clear water are stainless steel cased bore- holes.

Jan 1, 1982

By H Utama, hi, A Suw

PT. Indo Muro Kencana (PT.IMK) is gold and silver mine located in Central Kalimantan province, Indonesia. Mining activities in PT.IMK is conducted in Bantian pit area by applying surface mining method and using combination of excavator and hauler (articulated dump truck and rigid haul truck) as the transportation for ore to the crushing plant and waste material to the waste dump. Current blasting practice is ore-waste blasting. Ore-waste blasting is the term where the ore and waste rock are blasted in the same blasting process. Blasting is conducted by using nonel initiation system. By multiple pits operation, monthly powder factor is varied from 0.23 kg/t to 0.27 kg/t. Emulsion blend with density 1.15 g/cc is used as bulk explosive. At this stage, the concept of geoblast is proposed as an engineering tool for Drill and Blast engineering practice in PT.IMK. In addition, there is a need to maintain rock fragmentation by blasting, to maintain monthly powder factor, and to maintain excavator’s productivity. Next, the concept of scaled depth of burial (Chiappetta and Treleven, 1997) and the concept of blastability index (Lilly, 1986) are proposed as geoblast’s tools to improve blasting practice in PT.IMK. It is expected that rock fragmentation by blasting, explosive consumption and excavator’s productivity will be maintained by integration of geoblast and drill and blast engineering. Furthermore, the objective of this paper is to integrate geoblast and drill and blast engineering in order to create an engineering guideline in PT.IMK. Additionally, blasting trials with air decking application is proposed in order to support the geoblast’s improvement. It is planned that these blasting trials will be conducted in 2022. In conclusion, it can be seen that integration of geoblast and D&B engineering in PT.IMK is relevant to improve current drill and blast current practice and applicable to maintain rock fragmentation by blasting.

Nov 29, 2022

By J E. Wajon

This paper discusses the background, requirements, need and content of plans for management of drinking water self-supplied to mining-related operations, including construction camps, especially in remote areas of Western Australia. The paper discusses the importance of cooperation between regulators, the mine site operator and the consultant in preparing a plan fully compliant with the Australian Drinking Water Guidelines to protect the quality and safety of drinking water supplied to mine sites. The paper outlines some of the issues that need to be addressed in preparing a drinking water quality management plan, such as hazard identification, risk assessment, the multiple-barrier approach and the concept of critical control points. Data requirements, monitoring, incident management, training and reporting are also covered.CITATION:Wajon, J E, 2013. Drinking water quality management for mining operations in Western Australia, in Proceedings Water in Mining 2013 , pp 321-328 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 26, 2013

ASHBEL WELCH, LAMBERTVILLE, N. J.: Dr. Dudley has given the wear of steel rails under four different conditions. He arrives at the conclusion that the softer rails, or those that from their composition ought to be softer, wear better than the harder. But there is another condition which has an important bearing on the subject, and, should not be overlooked,-the weight on a wheel. With the lighter weights of the past, the softer rails may have worn best; with the heavier weights of the future, the harder may wear best. Weights will probably be increased up to the capacity of steel to bear; then doubtless the harder steel will wear best. A leaden rail with ten pounds on a wheel might carry millions of tons, but with one hundred pounds on a wheel, it would be destroyed by a few thousand tons. So in the days of iron rails, my experience was that the softer rails under light machinery stood better than some of the harder; but under heavy machinery the softer were much the most rapidly destroyed. His doubtless the same with steel. The pounding motion of the wheels loosens or spreads the particles of a thin film of steel; the pull lengthwise on the rail de- * Metallurgical Review, vol. i, page 1. † The remarks as here given, as in the previous discussion on steel rails, have all been written out or revised by the participants in the discussion, and represent, therefore, their mature views. It has been thought that this plan, when it can be carried out without doing any of the speakers injustice in debate, is much to be preferred to a strictly verbatim report. The remarks of Mr. Chanute were sent to the secretary after the. meeting, and although they did not form a part of the actual discussion, there can be no doubt of the desirability of including them in this report. The papers under discussion were “Rail Specifications and Rail Inspection in Europe,” by C. P. Sandberg ; " The Wearing Capacity of Steel Rails in Relation to the Chemical Composition and Physical Properties," by C. B. Dudley, and a Rail Patterns," by A. L. Holley. T. M. D., Secretary.

Jan 1, 1881

By Y. Y. Li, Q. Chen, Y. X. Cai, Q. Zhang, S. Mao

"Due to the influence of combustion conditions, the fly ash produced by some power plants has the problem of high-carbon content. The unburned carbon in fly ash can be removed by flotation, and the decarbon tailings should reach the national standard level I fly ash. The fineness of the requirement is one of the important indicators and is also an important factor affecting the tail ash activity. In this paper,adopting two methods investigate the effect of particle size on the flotation index: one is direct flotation of fly ash, and the other way is wet grinding + flotation of fly ash, comparing the two methods and selecting the appropriate process,which provides a way for the effective utilization of fly ash. INTRODUCTION Fly ash is a solid waste discharged from coal-fired power plants. The annual amount of emissions of fly ash are very large in China. The amount of fly ash were discharged from coal-fired power plants are increasing gradually, and the amount of fly ash stored has exceeded 2.5 billion tons, but the comprehensive utilization of fly ash is not high, which brings about a huge environmental problems( Lu et al.,2011). Carbon is a harmful component of fly ash in cement and concrete application (Zhang et al.,2008). Fly ash decarburization is an essential link to improve the utilization efficiency of fly ash and the reduce pollution ( Yang et al.,2012). Carbon is selected from fly ash to make full use of fly ash resources and improve utilization of fly ash (Li et al.,2008). In this paper, the flotation decarburization of high-carbon fly ash is studied, through comparing the grinding and not-grinding processes, optimizing the separation process of fly ash, which provides a way for the effective utilization of fly ash."

Jan 1, 2018

By Armando Vazquez

When water enters the EAF, some chemically dissociates to H2 while some remains as H2O vapor. Depending on operating conditions the levels of combustible gases (CO and H2) and H2O are continually changing throughout the course of any individual heat and on a heat-toheat basis. The EFSOP® system has been implemented in more than 80 installations as a powerful tool to reduce furnace operation costs but with water detection technology the off gas technology is a valuable solution to improve safety. This paper describes the latest results when using Tenova Goodfellow’s new standalone water detection technology that for the first time provides real-time analysis of both H2O vapor and H2 from start-to-end of a heat. It involves a newly designed water cooled probe and heated line that eliminates condensation during off-gas sampling and an analyzer equipped with a proprietary system for analyzing both H2O vapor and H2.

Jul 30, 2018

By D Henderson, M Germain

The beneficiation of iron ore deposits to yield haematite and magnetite concentrates for steel making processes typically require the use of one or a combination of wet processing techniques based on gravity, magnetic or froth flotation processes. With the need for more cost-effective technologies with a lower water demand, a re-examination of dry processing techniques has been initiated. For example, a dry processing capability may offer an advantage where suitable quality and quantity of process water hinders the development of a particular resource. This paper describes recent laboratory test work for the production of high grade concentrates using dry electrostatic techniques for -300 ¦m haematite and magnetite ores and compares them with magnetic separation techniques.

Jan 1, 2009

By James A. Bachmann, Christopher J. Gray

On December 26, 1994, at 1:00 am, Santa Fe Pacific Gold's Twin Creeks Mine experienced a major highwall failure involving over 2.5 million tons. The resulting effects of this slide were thousands of ounces of gold that were now deferred and an unstable wall above which made mining the slough material unsafe.

Jan 1, 1996

By M P. Simpson, J L. Mauk

The Golden Cross, low-sulfidation, epithermal deposit shows a number of features that are directly or indirectly related to boiling hydrothermal fluids. Occurrences of lattice calcite and their quartz pseudomorph equivalents in veins, and occurrences of adularia in veins and in the surrounding altered rocks in the vicinity of ore, are both direct evidence of deposition in the presence of boiling hydrothermal fluids. Loss of carbon dioxide causes calcite deposition (platy variety) near the level of first boiling, while adularia deposits due to the attendant pH increase along the cooling flow path. Indirect evidence of boiling include crustiform-colloform quartz banding, late massive calcite veins, clay-carbonate alteration in the shallow and peripheral parts of the ore zone, and the restricted vertical interval of precious metal mineralisation. The colloform quartz banding strongly resembles the banding in amorphous silica deposits found in geothermal surface pipes. This implies that fluids ascending the Empire Vein structure were saturated in amorphous silica. If so, then they must have undergone phase separation, which initiated at considerable depth (e.g. =1000 m) and very hot temperatures (e.g. =300¦C). On the basis of stable isotope data, late massive calcite veins appear to have deposited from CO2-rich steam-heated waters. Calcite deposited along heating paths as these waters descended into the upflow zone during late stage collapse of the hydrothermal plume. In active systems, such steam heated waters form by deep boiling. The high CO2 contents of these waters promote hydrolytic alteration and the formation of clay-carbonate alteration. Reaction path modelling using CHILLER and a deep, Broadlands-Ohaaki water as an analogue, shows that minerals deposit along boiling flow paths over discrete spatial intervals. Calcite and adularia deposit near the site of first boiling, followed by gold and then by amorphous silica. For deep boiling starting at 300¦C, these minerals deposit over a path length that exceeds 1000 m. The distribution of banded quartz and gold at Golden Cross are consistent with such a boiling model. However, the elevation of first boiling must have fluctuated over 500 m to account for the coincidence of lattice quartz (pseudomorphs of platy calcite) and adularia, crustiform-colloform silica and gold over distances of a few centimeters in veins. We deduce that a downward propagating boiling front and expansion of two-phase flashing in a flowing water column occurred during episodes of high vertical permeability and fluid flux in the Empire vein structure.

Jan 1, 2000

To develop a business case that promotes adoption of noise controls by reducing barriers to industry acceptance and enhancing drivers that foster their implementation. Background Over 75% of the U.S. mining workforce is exposed to hazardous noise, putting them at risk of noise-induced hearing loss (NIHL). Consequently, coal miners suffer high rates of hearing impairment that increase to 70%-90% by retirement age. To address the noise problem for coal miners, researchers from the National Institute for Occupational Safety and Health (NIOSH) first determined that the continuous mining machine (CMM) ranked first among machines associated with reported coal noise overexposures. Further studies found that most CMM noise is generated by three component systems on the machine: dust collection, cutting, and conveying. Of these systems, the on-board chain conveyor was found to be a dominant noise source. Noise generated by the conveying system was addressed through the development of a urethane-coated flight bar chain. The coated chain, shown in Figure 1, has demonstrated an 8-hour time-weighted average (TWA) reduction of operator exposure by 3 dB(A). It has since been accepted by the Mine Safety and Health Administration (MSHA) as a "technologically achievable" noise control for CMM operators who are exposed to noise that exceeds the MSHA permissible exposure level. Having demonstrated the noise reduction performance of the coated chain, NIOSH has assembled information into a business case that can be used by operations considering adopting the chain at their worksite.

Dec 1, 2009

By Nicholas Macrae Steven

Abstract - The Shaba-type Luamata Cu-Co(-Ni) deposit (11°50_S, 24°28_E) is located in a tectonic slice of Katangan Roan Supergroup (Mines Group) sedimentary rocks, surrounded by younger Kundelungu Supergroup lithologies in the external fold and thrust belt of the Lufilian Arc. Luamata is a classic central African copper clearing in dense woodland, visible as a tonal botanical anomaly on Landsat imagery. Supergene Cu-Co mineralization (especially malachite and subordinate chalcocite, digenite, covellite, and copper and cobalt oxides) and, probably hypogene, bornite, and chalcopyrite are hosted by altered, but essentially unmetamorphosed, moderately dipping, dolostones and dolomitic shales. Alteration products include talcose dolomite, sericite rocks and intense silicification and brecciation. Friable yellow shale is best mineralized with cobalt (up to 0.43 wt%), whereas, highest copper grades occur in brecciated, silicified shale (up to 13.5 wt% CuO). Soil copper and cobalt contents are up to 2.2 and 0.6 wt%, respectively. A newly identified nickel zone (where soil contents exceed 0.1 wt% Ni) fringes the Cu-Co deposit. Polymictic, matrix-supported breccias with a calcareous matrix that underlie the Cu-Co deposit are interpreted to be fluidization breccias related to thrust tectonics and the emplacement of the Mines Group slice. Although small compared to the Kolwezi district Shaba deposits in the Democratic Republic of the Congo, Luamata exhibits all the classic features of an ore deposit type (with low calcite contents), whose high metal concentrations could potentially be very profitably exploited by low-cost opencast mining and hydrometallurgical recovery methods.

Jan 1, 2000

By Brian J. Gorva

The key objective of forming a cartel is to increase profits to members of the cartel by taking the following action: a) control output; and b) control price. However, while attempting to obtain monopoly profits the cartel members have to contend with costs associated with cartelization and such costs include the following: political costs; the cost of coordinating output and price; organizational costs (such as cheating); and administrative costs (such as the cost of attending cartel meetings). The objective of commodity exchanges is to provide an open, free market where buyers and sellers may openly complete transactions and pricing information can be immediately disseminated. These transactions include the following: a) to provide facilities for "hedging", or transferring price risk from buyers and sellers of physical commodities to "speculators" through the medium of buying and selling futures contracts, and b) taking physical delivery of metal on due dates.

Jan 1, 1983