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By J. F. Liu, L. Chen, C. P. Wang

"Calcite-cemented joints abound in the rock masses of Beishan area, which is the most potential area for the high-level radioactive waste (HLW) disposal of China. The mechanical properties of Beishan granite containing a calcite-cemented joint with a dip angle of 82° was investigated under uniaxial compression and the acoustic emission (AE) characteristics were also studied in this paper. Compared to intact granite, the calcite-cemented joint caused a decrease more than 50% in uniaxial compressive strength and a decrease more than 90% in shear strength. The Young’s modulus was also decreased, while the circumferential deformation of jointed granite was sharply increased. The AE monitoring system successfully recorded the process of micro-crack development and the results indicated that the risk of rock-burst could be reduced due to the appearance of calcite-cemented joint.INTRODUCTIONThe properties of jointed rocks differ considerably from that of intact rock. Due to the difficulties in specimen preparation, analogue experiments with artificially prefabricated fractures are often used to study the mechanical behavior of jointed rock (Chen et al. 2012; Kulatilake et al. 2001; Singh et al. 2001). However, natural joints are not quite similar to the artificial fractures and it is necessary to investigate the mechanical behavior of jointed rocks. Xie et al. 2011 studied the mechanical properties of marbles with natural joints by uniaxial compression tests and found that the uniaxial compressive strength of jointed rock is greatly decreased. With the unaxial compression tests, Jacobsson 2005, 2007 tested the intact and jointed granites, which were taken from the potential site for high-level radioactive waste (HLW) disposal of Sweden. However, no significant difference in strength or modulus was found. The above research results are inconsistent and it indicates the complexity of the mechanical properties of natural joints."

Jan 1, 2015

By J. W. G. Hannon

FOLLOWING the experimental work of Denny, Robson, and Irwin, and the clinical investigation by Crombie and Blaisdell, an investigation of aluminium therapy was begun at Washington, Pa., which is situated in a very large industrial section of the State. Some of the men to be studied were from plants manufacturing silica brick, refractories used in steel and glass manufacturing, and semi-porcelain table-ware; others were workers in foundries, sand blasters, and men engaged in the quarrying of ganister rock. This group of workmen gave an opportunity to study the effects of aluminium on various types of silicosis which differed somewhat from that found in hard-rock miners. EXPOSURE In their occupations, the men studied were exposed to silica dust concentrations ranging from 17 to 97 per cent free silica. In the silica brick industries, the unfired product averages 96 per cent silica in the form of quartz, whereas the fired brick contains 50 to 62 per cent cristobalite plus 17 to 30 per cent tridymite, forms of silica that, on account of their higher solubility, are more toxic than quartz. The operational dust counts in the plants varied from 15 to 9,500 particles per c.c., and the median particle size from the aerial samples was 1.0 micron for the green product and 2.0 microns for the fired product. The length of exposure varied with the occupation as well as with the individual plant, but disabling silicosis could be produced in less than four years in certain exposures. The average time needed to produce radiological silicosis in those susceptible to this disease was eight years. Some of the men in our series of cases have been treated as long as fifteen years after exposure had ceased, and have improved under treatment.

Jan 1, 1944

Ni and samaria-doped ceria (Ni-SDC) cermet are desirable materials for making a solid oxide fuel cell anode working at intermediate temperature (800°C or lower) due to its good ionic/electronic conductivity at the reduced operating temperature. An advantage of the use of a Ni-SDC anode is the enlargement of the effective reaction zone in the interfacial area between the anode and the electrolyte. As a result of the mixed ionic/electronic conductivity of the anode, the electrode reaction rate is enhanced. Investigations into the properties of the ceria-based anode reveal that the performance of the anode is closely related to its microstructures, which are dependent on the composition and fabrication conditions of the ceramics. In this paper, a method for quantitative characterization and correlation of Ni-SDC cermet microstructures to the performance of an anode is investigated. A series of Ni-SDC anode samples are prepared by screen-printing (SP) and spin-coating (SC) techniques, and different microstructures of the samples are obtained through controlling the SP or SC conditions and the sintering temperature. Individual phases (Ni, SDC and pore) in the tri-phase boundary (TPB) microstructures in the electrode are differentiated and segmented from each other in optical and SEM images based on the differences in refractivity and atomic contrasts among the phases. The geometric properties of the segmented phases are characterized using image analysis methods, so that a quantitative skeleton illustrating the TPB microstructures of the Ni-SDC electrode is obtained. Statistical analysis of the distribution of the three phases in the TPB microstructures is performed and the relationship of the microstructures with the optimum electrode is interpreted in terms of the microstructure analysis data.

Jan 1, 2005

By K-A. Adamson

If fuel cells and hydrogen are to become a mass market reality a substantial amount of further research and development needs to be undertaken. Work in hydrogen storage, production, the economics of all aspects of fuel cells and hydrogen, materials balances, and product integration are just a few of the areas that are under focus. Setting R&D targets, and providing R&D funding are therefore areas that are central to the long term development of the market, and areas in which a number of governments worldwide are highly active. Some governments, such as Japan and Korea, have set a number of very ambitious, highly focused, long term targets and are backing this up with substantial funding, others such as the EU are working on a more integrated approach, wrapping some fairly fundamental R&D into large integrated projects which run in combination with a number of other market aspects, such as public acceptance and roadmapping. The US is slightly different, in that although is has a number of long term programmes and targets, FreedomCar and SuperGen being just two, the levels of funding are set annually with the passing of each years Fiscal Budget. This paper takes three high profile regions and analyses the R&D targets and funding levels for fuel cells and hydrogen. Criteria that will be looked at include: Time frame of target(s), level of ambition, funding issues, including: Funding windows, levels available, funding barriers, overall programme goals. The added value to this paper is that it will provide a clearer picture of where each region is heading, what are its strengths and weaknesses, in terms of R&D and where there may be areas for potential international collaboration.

Jan 1, 2005

By A. Gillis

"In order to obtain the equipment necessary to automate the equipment it was decided that the Department of Mines and Milltronics would jointly survey the circuit. This survey involved a metallurgical study by the Department of Mines and Milltronics took sound recordings during manual operation, checking in circuit bottle necks and determining the number of sensors that could be applied.The conveyer is driven by 2 PIV drives, each has a variable speed of 3/ 1. The cross conveyer that feeds directly into the rod mill feed chute will contain an automatic sampler and will eliminate the necessity of stopping the belt feeders to take samples. At present, hourly samples are taken from this point and the circuit is upset and cycling results.The Adequate scale is very close to the rod mill to totalize and thereby give a continuous indication and the second purpose is to take a signal from it and control the solution addition to the rod mill.A pneumatic positioner was obtained and put on the scale which produces a 3 tp 15 psi signal which is proportional to the actual tonnage going across the scale. This signal was fed to a bias loader which was mounted on the control panel. From there the operator can set the amount of solution that is wanted by the rod mill. No matter what the feed rate is, the signal coming from the bias loader will follow it automatically. This in turn goes to the pneumatic solution valve (1 ½” ) and the solution goes in with the feed to the rod mill. This is only part of the solution required for dilution since the rest of it is used as a force jet for the feed to the rod mill."

Jan 1, 1965

By Mike Power

Geophysical techniques have played a pivotal role in northern kimberlite exploration since the initial discovery at Point Lake in 1991. In the Slave Craton and surrounding regions, there are definite contrasts in physical properties between kimberlite intrusions and surrounding bedrock. Kimberlite commonly displays higher magnetic susceptibility, distinctive remnant magnetism, low electrical resistivity and lower density than surrounding rocks. In addition, the distinctive geometry of kimberlite pipes is reflected in geophysical responses which further facilitates target discrimination. There has been an evolution in geophysical exploration strategies over the past 12 years. Helicopter total magnetic field and electromagnetic (HEM) surveys have proven to the most cost-effective means of conducting first pass investigations in prospective areas. During the early 1990's, total magnetic field and frequency domain electromagnetic surveys were virtually the sole techniques employed during follow-up surveys. Inevitably, the initially high rates of kimberlite discovery declined in the areas surrounding the original finds. Marginal magnetic and EM anomalies were all that remained to be tested and this spurred interest in the improvement of existing interpretation algorithms and in the application of additional complementary techniques to reduce the exploration risk. Gravity has become a popular third survey following the deployment of the Falcon (TM) airborne gravity gradiometer system by BHP Billiton in 1999 and improvements in ground techniques. Ground penetrating radar (GPR) has proven to be particularly useful in delineating kimberlite pipes following drill discovery and in exploring for kimberlite dykes in settings where indicator mineral trains indicate such targets are likely. Seismic methods have been tested for both reconnaissance and delineation but remain underemployed. Given the high cost of drilling in the North and the proven success of geophysical techniques in reducing exploration risk, it is likely that an increasingly diverse range of geophysical techniques and innovative interpretation techniques will continue to be applied in kimberlite exploration.

May 1, 2003

By W. Andrew Falls

Although we have yet to reach the midway point in the decade, the copper concentrate market has already witnessed some of the most volatile swings in history, moving from record high treatment and refining charges in 1991-92 to historic lows, in real terms, during the past year. What has been the cause for such volatility? By and large the swings can be attributed to factors of supply and demand in the "custom" copper concentrate market. For example, two relatively recent events which had a major impact on the supply-demand balance were the shutdown of the Bougainville copper mine in Papua New Guinea in 1989 due to rebel insurgency and the startup of the La Escondida mine in Chile in 1992. The first event, threw a balanced to slightly surplus concentrate market into a substantial deficit, forcing treatment terms down as smelters, caught short by the loss of concentrate supplies scrambled to cover their positions. The second event, brought over 300,000 mt per year of new copper in concentrate to the market, more than reversing the losses from the Bougainville shutdown. In combination with other additions to mine capacity via new mines or expansions, the custom concentrate market moved into a huge oversupply in 1991-92 and many mines found themselves unable to place uncommitted tonnage. But even this event was quickly overcome by the use of underutilized capacity at non-traditional buyers, such as those in the C.I.S., Zambia, or those which were not traditionally buyers of custom materials. All of this has happened in the space of five short years, a mere snapshot in the history of the market. I'll return to these points a little further on, but first I would like to review the fundamentals which govern the copper concentrate market.

Jan 1, 1995

By Bryon Bisiaux, Walter Valery, Sonny Mwansa, George Amonoo, Adrian Dance

"Newmont Ghana Gold Limited’s Ahafo operation have been working with Metso Process Technology & Innovation (PTI) since early 2009 to increase mill throughput from a combination of controlled blasting practices and optimised primary crusher and grinding circuit conditions. For such Mineto-Mill projects, PTI’s methodology is termed Process Integration & Optimisation (PIO).Ahafo operate a SAG mill, ball mill and pebble crusher (SABC) circuit that processes a range of primary ore of varying hardness from different pits which is blended with soft oxide material. The PTI study focussed on ball mill limited material from the Apensu open pit.Following a benchmarking study of all blasting, crushing and grinding practices in January 2009, PTI recommended changes in both blasting and crushing conditions in order to generate a finer feed size to the SAG mill. Additional operating changes in the grinding circuit were recommended.A series of trials were conducted in November 2009 where three blasts were fired using a different blast design (hole diameter and explosive type) in the same area of the Apensu pit as the benchmarked material in January 2009. Top and bottom benches (or flitches) from each blast were sent exclusively to the grinding circuit and the material was tracked using PTI’s SmartTag™ system.The results from the six trials showed a significant increase in primary ore throughput at a reduced blend of oxide material. Ahafo have since standardised on these modified blasting conditions for all Apensu ore zones and have been able to sustain higher throughput compared to historical performance on similar material.This paper summarises the phases of the PIO project, the changes made in operating practices and the outcomes of the blasting trials that validated the predicted increase in mill throughput."

Jan 1, 2012

By R. Tessier, R. Grant, C. Bazin

"Brunswick Mining has investigated grinding media optimization for the purpose of improving the flotation feed and regrind product size distributions to enhance metal recoveries. The paper presents findings in the on-going testing of various sizes and shapes of grinding media. Breakage rates are used as an aid to assess the effect of grinding media. Results of empirical and phenomenological analyses demonstrate the importance of adequate selection of media sizes on the milling operation.INTRODUCTIONBrunswick Mining and Smelting operates one of the world's largest lead and zinc mine near Bathurst, New-Brunswick. The No. 12 ore body is an extremely fine grained volcanogenic massive lead, zinc, copper, silver, iron sulphide body between two metamorphosed sedimentary and felsic volcanic rock units. Pyrite content is about 60% with 20% non-sulphide minerals, mainly silica and chlorite. The operation is currently processing 10,500 tonnes of ore per day in conventional crushing, grinding, differential flotation and dewatering circuits. Details on the circuit can be found elsewhere (e.g. Hendriks and Ounpuu, 1985; Grant et al., 1991).The mill has operated for more than 25 years and despite the past milling experience, there has been much disagreement as to the required grind size. Since 1964, fineness of the flotation feed ranged from 60% to 80% passing 400 mesh (37µm) and averaged slightly over 71%in1992. Results from mineralogical analysis (Petruk and Schnarr,1981; Coleman, 1988), Brunswick metallurgical laboratory (Grant et al., 1991; Shannon et al., 1992) and Lakefield pilot plant tests (Hendriks, 1984; Hendriks and Ounpuu, 1985) clearly indicate that improved metal recoveries can be achieved by an increase in the fineness of grind, and more specifically by maximizing the amount of material in the 15-25µm range."

Jan 1, 1993

By J. C. Salas, A. Weishaupt, J. A. Guzman

The origins of the electrorefining process date back to 1869, when the first ER cathodes were produced at Pembrey, South Wales. By the time that Pembrey was closing, Chuquicamata tank house was under construction, initiating in 1915 a long history of electrolytic cathodes production. Initially electrowon cathodes and later electrorefined cathodes were produced. During the history of Chuquicamata tank house, there have been several challenges associated with the quality demanded for electrolytic copper. Among them, the transformation from electrowinning to electrorefining in 1952, the onset of the direct commercialization of ER cathodes and the phase out of wire bars in the 80s, several technological changes including the implementation of permanent cathodes, and certainly the constant increase in complexity of the anodes refined. This paper explores the manner in which Chuquicamata has addressed these challenges and examines its links to process characteristics, which have been necessary to maintain a product quality according to market requirements and a brand, “CCC”, that is widely recognized worldwide. INTRODUCTION Located in the north of Chile, in the Atacama Desert, Chuquicamata is an open pit copper mine that for many years has played a relevant role in the global and local mining industry. Known from prehispanic times, the Chuquicamata deposit was initially developed between 1912 and 1915 by the Chile Exploration Company, the operating company of the Chile Copper Company controlled by the Guggenheim Brothers in the USA (Yeatman, 1916). Officially inaugurated on May 18th, 1915, by the President of Chile who pressed a button in Santiago sending a telegraph signal to the power generation plant specially built in Tocopilla, 1500 km north. It signaled the beginning of generating energy, sending it to Chuquicamata, another 140 km east (“El mineral de Chuquicamata”, 1915), marking the beginning of its industrial operation.

Jan 1, 2019

By Hammenm R., J. Hammen, C. Hammen

"The production of salable Rare Earth Element (REE) products necessitates a sequence of chemical separation steps between the mine and market commodities. The effectiveness of the chemical separations that purify REE salts is critical to the success of the producer, as the purity of REE salt products affects their market price. This is due to the fact that impurities in REE salts, even at low levels, can be deleterious to the function and usability of the end product. The purification of REE by removal of low levels of contaminant has been referred to as "product polishing". The technologies commonly in use for product polishing, solvent extraction (SX) and ion exchange (IEX) are challenged by the availability of separation chemistries to separate the contaminant from the desired REE salt. In simple terms, if a product specification is 99.9% purity, the SX or IEX separation reagents need to have at least a 999:1 selectivity ratio. Significant testing has been carried out on the use of solid phase extraction (SPE) columns to extract low-level impurities such as aluminum or zinc from REE product streams. The SPE columns are nano-composite materials that have rapid equilibration kinetics with the solutes being processed by the columns. The SPE matrices have been modified with chelating ion exchange ligands that bind the contaminating ion with great selectivity in residence times of a few seconds. Thus, REE streams with 1 to 2% of contaminating aluminum ions, have been polished to >99.99% purity. In this paper, results are presented on the removal of aluminum impurity from a didymium (neodymium+praseodymium) product stream using SPE technology. The selection of the SPE medium and the process steps to treat the feed solution for aluminum removal and ultimate stripping and recycle of the solid phase extractant are discussed."

Jan 1, 2014

By G. W. Zhang, Changsha Research Institute of Mining and Metallurgy, X. Xiao, Y. Long, L. L. Huang

"The paper presents a scale-up and design method of vertical screw stirred mill, in which the closed circuit of mill and hydrocyclone was assumed as one factor, theoretically regardless the affects inside system of the mill and hydrocylone. The specific energy is chosen as a scale-up criterion, based on the premise that when fed the same feed material, mills of different sizes delivering the same specific energy will yield products.Batch grinding tests are conducted to determine the specific energy, and combined with industrial production data, scale-up and design of vertical screw stirred mill for industrial production are accomplished. Having developed this method for the vertical screw stirred mill used in regrinding duty of iron ore in Ma Steel, it has now been successfully applied in other installations.INTRODUCTIONThe Towermill was developed in Japan in the 1950s, by the Tower Mill Kubota Corporation, it was fine and ultra-fine grinding mill of the metallic ores and concentrates. Due to the rapid development of metal mining and useful minerals disseminated fine, fine grinding and ultrafine grinding equipment has also been more wide used in minerals processing industry. Typical fine and ultra-fine grinding mil are the Vertimill and Stirred Media Detritor (SMD) Mill of Metso, Eirich Towemill, Outotec HIGmill, FLSmidth VXPmill, Xstrata Isamill and the vertical screw stirred mill (JM) of CRIMM, etc.JM series of vertical screw stirred mill were invented by Changsha Research Institute of Mining and Metallurgy in the 1980s. Energy saving and consumption reducing have been achieved through the optimization and engineering practice. More than 500 units JM series of vertical screw stirred mill are used in the iron ore, copper ore, copper-molybdenum ore, molybdenum ore, Pb-Zn ore and Au ore."

Jan 1, 2016

By Wengui Su, Qi Zhang, Junce Wang, Zhijun Ma, Xingyuan Weng

"Mesoporous materials with large specific surface area, pore size, and pore volume have been widely used in many fields such as ion exchange, gas separation, adsorption, and catalysis. Mesoporous materials prepared using natural zeolite have the advantages of both acid and alkali resistance. In this work, mesoporous materials were prepared using natural zeolite as the starting material and diethylenetriamine (DETA) as a template. The resulting samples were characterized using scanning electron microscopy (SEM), X-ray diffraction (XRD) and N2 adsorption-desorption experiments. The influence of the crystallization temperature and crystallization time on the specific surface area, pore volume, pore size, and morphology of the resulting mesoporous materials are also discussed. Our results show that for an increase in both the crystallization temperature and time, the average pore size first increases then decreases, while the specific surface area first decreases then increases. Based on this work, we concluded that the optimal crystallization temperature was 2003 and the optimal crystallization time was 60 h. These conditions gave an average pore size of 17.93 nm, a pore volume of 0.048 cm3g-1, and a specific surface area of 16.48 m2g-1.INTRODUCTIONMesoporous zeolite, as the name implies, is a highly porous crystalline zeolite. This material is of interest due to its high hydrothermal stability, its adsorption and diffusion properties for macromolecules, and its excellent selectivity and activity as a catalyst. In recent years, it has become a hot spot among research of porous catalytic materials and has been widely used in petroleum and natural gas processing, fine chemical processing, various adsorption and separation tasks, and other uses (Carvalho & Urquieta- Gonzalez, 2015; Teh, Triwahyono, Jalil, Mukti, Aziz, & Shishido, 2015)."

Jan 1, 2016

By Robert B. Parsons

"During hard times, the focus on tax issues makes a slight change in direction. Mining companies contemplate the tax treatment of transactions and circumstances which are the product of a difficult financial environment. Some of these issues are discussed in this month's edition of Tax Notes.Every industrial sector in Canada is undergoing a major restructuring of some form, and the mining industry is not an exception. The longest recession since the Great Depression continues to affect the economy. Mining firms seek to bring their debt/equity ratios into line, and try to replenish depleted retained earnings by selling assets. This month, Tax Notes briefly examines some of the tax issues which are generally encountered during the course of such a restructuring process.Debt SettlementOne question which commonly arises during hard times concerns the tax treatment of a "" gain "" realized by a debtor on the settlement of a debt. Consider, for example, a simple situation where a creditor wants to protect itself from further losses, and makes a deal with the mining company to accept a cash payment of $8 million in full settlement of a $10 million loan. In financial terms, the debtor has made a $2 million gain on the settlement of the debt. What is the tax treatment of that gain?The Income Tax Act (the Act) contains provisions in section 80 of the Act and in section 5400 of the Income Tax Regulations which deal specifically with this question. First of all, it is noted that the $2 million gain is not brought directly into income for tax purposes. However, as indicated below, the gain could affect the debtor's income indirectly to the extent that certain of the debtor's tax pools must be reduced by the amount of the gain."

Jan 1, 1993

By R. D. Brown

"Concerns over possible additional involvement of governments in Canada's mining industry and its adverse effects on the industry 's growth were a frequent topic of conversation at the recent Annual General Meeting of the CIM.Still painfully fresh in the minds of industry leaders are the disastrous results of the federal/provincial scramble over resource revenues which followed the relatively high metal prices witnessed in 1973/1974. At current metal prices, it is not surprising, then, that a nagging fear persists that these governments may once again restructure tax and other rules to the detriment of the industry and the country.This month, Tax Notes recalls some of the progress which the industry and governments have made in 1979 in the taxation of the resource sector, and urges that higher metal prices be viewed in light of the costly exploration, development and production efforts which will be required for the industry to continue to play its important role in our economy.IntroductionAt the Annual General Meeting of The Canadian Institute of Mining and Metallurgy, held in April, 1980, it was abundantly clear that there is widespread concern in Canada's mining industry that this country's tax regime may once again be blasted by ill winds of change.A stable and more favourable tax climate, as well as higher metal prices and profits, made 1979 almost a golden year for Canadian mining. However, from the tax viewpoint at least, there are some spots on the silver lining as apprehensions grow that the well-heralded battle between federal and provincial governments over oil and gas may spread to the mining sector, with serious damage to the industry and its newfound federal-provincial cooperation."

Jan 1, 1980

By G. Armand, A. Noiret, D. Seyedi, J. Morel

"Clay formations in their natural state exhibit very favorable confining conditions for repository of radioactive waste because they generally have a very low hydraulic conductivity, small molecular diffusion and significant retention capacity for radionuclides. Nevertheless, one concern regarding the hydromechanical behavior around drifts in such claystone is the associated pore pressure field disturbance during excavation works. In the short term, the very low permeability leads to an almost “undrained” condition, meaning that the stress change due to face advance will create volumetric strains leading to an increase or decrease of pore pressure. If the effective stresses reach the failure level, the induced damage around these excavations might change the favorable properties of such formations. To demonstrate the feasibility of a reversible deep geological disposal of high-level and intermediate-level long-lived radioactive waste (HLW, IL-LLW) in the Callovo-Oxfordian claystone (COX) formation, the French national radioactive waste management agency (Andra) started in 2000 to build the Meuse Haute-Marne underground research laboratory (M/HM URL). The present paper illustrates observed pore pressure changes during excavation of drifts (˜5 m diameter), of micro tunnels (˜0.7 m diameter) and a borehole (˜0.15 m diameter). All these openings are parallel to the major horizontal stress at the main level of the M/HM URL. In drifts parallel to the major stress (i.e., when the initial stress field in the drift section is quasi-isotropic) an important increase followed by a drop of pore pressure is observed in the horizontal plane at the drift wall. These observations emphasize the impact of the in situ stress state and rate of excavation on the pore pressure and provide important insight of the hydro mechanical behavior of the COX claystone and the relationship between pore pressure and excavation induced fractures zone."

Jan 1, 2015

By Robert B. Parsons

"This article is based on a paper presented by Jim Scott at the 1988 annual convention of the Prospectors and Developers Association of Canada. The paper suggests a number of factors that might be taken into account in negotiating royalty terms.IntroductionRoyal ties are a part of mining life in Canada. They are used by many kinds of individuals in many kind s of situations. Prospectors commonly take royalty interests back when they transfer claims to development companies. Mining companies disposing of undeveloped (or sometimes even developed) properties are often paid at least in part by royalties. Royalties are even used by institutional investors with no other connection with the resource industry.Such different royalty holders have different investment goals, different cash flow requirements, and different risk / return preferences. These differences have given rise to a number of different royalty type s. These types range from the simplest cents-per-ton royalty (where the operator pays a royalty at a fixed rate per ton milled) to net smelter return or ""NSR"" royalties (where the royalty is based on a percentage of the operator's NSR) all the way to net profit interest or ""NPI"" royalties (where the royalty is based on the operator's bottom-line net profit),The fundamental difference between the many royalty types is in the risk/ return relationship. The cents-per-ton royalty, for example, is relatively risk-free. Of the many economic factors which affect a mine, the only one which will affect the royalty holder is the amount of ore physically milled. On the other hand, the potential for significant gains under a cents-per-ton royalty is also very limited. The royalty holder will not share in any increases in the market price of the end product or any cost reductions achieved by the producer."

Jan 1, 1988

By Robert B. Parsons

"This article is based on a paper presented by Jim Scott at the 1988 annual convention of the Prospectors and Developers Association of Canada. The paper suggests a number of factors that might be taken into account in negotiating royalty terms.IntroductionRoyal ties are a part of mining life in Canada. They are used by many kinds of individuals in many kind s of situations. Prospectors commonly take royalty interests back when they transfer claims to development companies. Mining companies disposing of undeveloped (or sometimes even developed) properties are often paid at least in part by royalties. Royalties are even used by institutional investors with no other connection with the resource industry.Such different royalty holders have different investment goals, different cash flow requirements, and different risk / return preferences. These differences have given rise to a number of different royalty types. These types range from the simplest cents-per-ton royalty (where the operator pays a royalty at a fixed rate per ton milled) to net smelter return or ""NSR"" royalties (where the royalty is based on a percentage of the operator's NSR) all the way to net profit interest or ""NPI"" royalties (where the royalty is based on the operator's bottom-line net profit),The fundamental difference between the many royalty types is in the risk / return relationship. The cents-per-ton royalty, for example, is relatively risk-free. Of the many economic factors which affect a mine, the only one which will affect the royalty holder is the amount of ore physically milled. On the other hand, the potential for significant gains under a cents-per-ton royalty is also very limited. The royalty holder will not share in any increases in the market price of the end product or any cost reductions achieved by the producer."

Jan 1, 1989

By A. Khan, C. Ciriello, W. Oliveira

"The purpose of this paper is to demonstrate the value of Operational Readiness (OR) in the successful delivery of capital projects. OR can be captured using several technical and practical definitions:• To ensure that the capital project being delivered is capable of an effective start up, ramp-up as planned and a sustainable productive operation.• To function as intended when started, with the appropriate people able to run it.• To increase the value in delivering the product/service through established systems, processes and procedures, while simultaneously minimize risk to both the project and the business.Historically, mining and metallurgical capital projects concentrate efforts on cost and scheduling during the implementation and design phases. The completion and subsequent handover of the operational unit is the main objective.When reviewing the mining and metallurgical industry’s capital projects, it seems many poor results and errors in terms of project design and ramp-up are self-inflicted, with the project neglecting to account for key aspects of the future operational plant. Interestingly, if the problems for the future plant occur during project implementation, they can be prevented during the project phase. It is required to connect the operational knowledge with the project in order to ensure an effective start up and operation.The benefits of OR will be shown to be applicable not only to mining capital projects but also to sustaining and business transformation projects. The paper also includes industrial examples showing both proper and improper use of OR techniques.The paper will cover 3 main areas of Operational Readiness: the OR model, OR related risk elements (i.e., risks associated specifically with the improper execution of OR) and conclude with OR specific case studies."

Jan 1, 2016

By Lar Liljeblad

"As demands upon the earth's natural resources continue to grow, exploration companies, mining organizations and others face the problem of the need to tackle increasingly more difficult strata to open up new reserves. Innovations in materials technology and tool design have steadily improved this capability, but none perhaps so drastically as a recently introduced cemented carbide in which tool wear resistance and/or toughness can be tailored precisely to the user's drilling needs.Introduction Until about forty years ago, the bulk of rock-drilling operations had to be carried out with hardened steels. Short life between re-grinds was common especially in abrasive rock formations. Shortly after World War II, Sandvik, Sweden, pioneered the development of sintered (cemented) carbide-tipped steel tools as a means of improving drill tool life. The new material was a composite of tungsten carbide and cobalt, the latter acting as a 'cement' to bind the wear-resistant carbide grains together, and the composite, in turn, was brazed to the steel. The immediate effect was a 100-fold increase in the service life of the tool.Intractable ProblemsWhile the carbide-tipped tools served the mining and quarrying industries admirably there were, nonetheless, some seemingly intractable limitations. The greater the wear resistance of the material - the quality for which it is selected - the more brittle it is. Also, rocks vary widely in hardness and abrasiveness and no single tool, either in terms of material or shape, meets every need. Specifically, for fast penetration of non-abrasive rock, toughness must be combined with a relatively sharp tool prome. Highly abrasive rock, on the other hand, demands a substantially broad area of extremely wear-resistant material on the tool if long bit life is to be assured. Between these extremes there are innumerable variations in rock"

Jan 1, 1991