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By Karl J. C. Harries

"12.1. NO DEPRECIATION/GAAPAll calculations and computations relating to the Royalty shall be carried out in accordance with generally accepted accounting principles consistently applied to the extent that such principles are not inconsistent with the provisions of this Schedule and the agreement attached hereto, it being specifically agreed that nothing herein contained shall permit, or be construed to permit, the Operator to deduct any amount for depletion, depreciation, amortization or any deduction that represents a non-cash outlay.Comment: In cases like net profit royalties where recoupment of prior expenditures is permitted, care should be taken to avoid any implication that depreciation may also be taken. It is only logical and equitable that Property Owners should not be permitted an apparent ability to “double dip” with respect to deductions. A provision like this example should accomplish the task. It will be noted that the example specifically contemplates that the negotiated arrangements will prevail over any requirements of GAAP. Accordingly, if the parties agree to an unusual formula for recoupment, it will not be set aside to accommodate GAAP requirements. Under GAAP, revenues and expenditures are accounted for on an accrual basis. In addition, it specifically prohibits the taking of non-cash deductions, which is in keeping with the concept of recoupment.Although in some ways the example states the obvious and could be considered redundant, its presence, especially in provisions contemplating recoupment, makes it clear to the financial people that there may well be some variations from normal practices dictated by GAAP, while at the same time confirming the availability of GAAP to fill any voids.The accounting profession often makes the caveat that application of GAAP is an “art”, not a “science”. GAAP do not provide a cure-all and can create problems that will have to be addressed. For example, GAAP contemplate that asset costs are to be reduced by investment tax credits, which can cause a problem for a payor with more than one mine."

Jan 1, 2003

By Michael P. Amsden

"THE ECSTALL CONCENTRATOR is situated adjacent to Highway 101 and the Ontario Northland Railroad, 15 miles east of Timmins, Ontario. Ore is delivered to the concentrator by rail from the mine, which is 17 miles northwest of the plant. Power and fuel are obtained from the hydro and natural gas lines which pass close to the plant site. Water is obtained from the Frederickhouse River, 6 miles east of the concentrator. The main concentrator building is a large structure 500 by 640 feet by 90 feet high and contains facilities for fine crushing, crushed ore storage, grinding, flotation, tin recovery, concentrate handling and reagent handling. Located in the same building are the machine shop, warehouse, metallurgical laboratory, pilot plant, men's change room, sample preparation area and an assay laboratory. The general concentrator layout is shown in Figure 47. Originally designed to handle 9,000 tons per day, the concentrator now treats 10,000 tons per day. Two different ore types are processed by selective flotation in three individual circuits to recover copper, lead and zinc concentrates. In 1973, another circuit was added to recover pyrite and tin concentrates from the combined zinc tailings of the three main circuits."

Jan 1, 1974

By G. Van Weert

In the spring of 2010 double refractory ores from historical stockpiles were processed through Barrick's Goldstrike pressure oxidation facility, thereby providing preg robbing feeds for a variety of metallurgical testwork. This paper describes the effects of amount, type, place and time of addition of activated carbons on CIL gold recovery and shows that native carbon in plant PDX'ed discharge solids can still preg rob gold loaded activated carbon.

Jan 1, 2011

By Sandra K. Zacharias

Brass, a deliberate alloy of copper and zinc, has been known since before Roman times. There are two main methods of making brass: (1) Cementation or calamine process - crushed zinc ore (calamine, ZnC03 , or calcined calamine, ZnO), is mixed with charcoal and small pieces of metallic copper and heated to about 900°C in a closed crucible, (2) Alloying - metallic copper and zinc are melted together in a reverberatory furnace. According to most modern authorities (e.g. Smith and Forbes 1955), the calamine process was the only one used in western Europe prior to the 18th century. At that time, the alloying technique began to take over, because metallic zinc was successfully produced on a large scale for the first time. Previously, this had been a problem because zinc vapourizes at 906°C or about the same temperature at which it can be reduced from its ore. Thus, some means had to be devised to collect and condense the zinc vapour (Tylecote 1976). Metallic zinc was known, however, earlier than the 18th century A.O. Several early finds have been made, including a rolled sheet of metallic zinc found in excavations at the Athens Agora dating to the 3rd to 2nd century B. C. (Farnsworth et al. 1949). The Chinese were producing zinc by at least the 10th century A. D. and, by the 17th century, Chinese zinc ingots were being imported into Europe by the Dutch East India Company (Needham 1974). Metallic zinc is also mentioned in several European documentary sources from the 16th century (e.g. Paracelsus, Agricola). This study traces the changes in Western brass making methods from Classical to Renaissance times by examining documentary and archaeological evidence.

Jan 1, 1999

By H. Agnerian

"A survey of 925 mineral property transactions worldwide was carried out between 1987 and 2004. These mineral properties with reported Mineral Resources include 457 gold properties, 322 base metal properties, and five platinum group element (PGE) properties. Based on constant Canadian dollars, the results of the survey indicate that:• In general, unit metal values in the ground (e.g. $/oz Au or $/lb Cu) have kept pace with the changes in the respective metal prices during the period of the survey.• A general decrease in unit gold values in the ground has occurred from about $57/oz Au in 1987 to about $11/oz Au in 2002 for Canadian mineral properties, with the exception of a peak of $58/oz Au in 1996.• A similar trend for mineral properties has occurred in the United States, but with lower unit values, in the range from $1/oz Au to $10/oz Au during the last three years of the survey. • Unit metal values in the ground for gold properties in Canada were higher than for those in the rest of the world.• Unit metal values in the ground for copper properties in Canada were in the mid-range compared with other countries in the rest of the world; the United States and Australia were higher and Latin America, Asia, Africa, and Europe were lower than in Canada.• Unit metal values in the ground for zinc properties in Canada were also in the mid-range compared with other countries in the rest of the world; Latin America and Europe were higher and the United States, Australia, and Asia were lower than in Canada.• Unit metal values for nickel properties in Canada were highest compared with other countries in the rest of the world, followed by the United States, Australia, Africa, and Asia.• Gold values in the ground in Canada have ranged from 6% to 14% (with an average of approximately 10%) of the gold price.• The unit values of base metals in the ground have been in the order of 2% of the quoted metal price, during the period of the survey."

Jan 1, 2006

By Karl J. C. Harries

Mineral Agreements and Royalties

Jan 1, 2003

By C. P. Patel

"The Sturgeon Lake Joint Venture volcanic massive sulpide deposit was discovered in 1970. Milling was started by Falconbridge Copper Ltd. at Sturgeon Lake in September 1974. The Sturgeon Lake pit and mill are located 88 kilometers by road northeast of Ignace, Ontario. IgnE1ce is a town of some 2800 people located on the Trans-Canada Highway, 241 kilometers west-northwest of Thunder Bay. The mill is treating an average of 1100 TPD producing separate concentrates of copper, lead and zinc. Initially, difficulties were experienced in achieving accept-able concentrate grades and recoveries but these were eventually overcome. This presentation describes current metallurgical strategy as practiced at the Sturgeon Lake mill.But first, a few words about the type of ore being treated. In geological terms the ore is classified into two main categories. They are the massive sulphides with underlying zones of stringer sulphides as illustrated in Fig. 1. The plan view is shown in Fig. 2. The areas of East-limb and North-limb are as shown. These last two ores have suffered enough alteration to cause problems during treatment. The massive sulphides consist of chalcopyrite, sphalerite, galena, tetrahedrite and small amounts of pyrrhotite among other gangue materials. The stringer ore is comprised of predominantly chalcopyrite intrusions into rhyolite and has lesser amounts of sphalerite and tetrahedrite. At present we are treating a predetermined blend of massive and stringer ores from zones that have been metallurgically tested to ensure compatibility with current treatment procedure in the plant. Ore responding to this treatment is classified as normal ore while the ore proving incompatible is classified as north-limb ore or east-limb ore."

Jan 1, 1980

By David R. Macedon

"Through the years, a wide variety of dust control methods have been utilized at mineral processing operations. While some have been successful, many have been highly ineffective. Dust Control systems currently in use include baghouse systems, fog systems, surfactant spray systems, and foam dust suppression. While baghouse systems can be effective, they are capitalintensive and costly to operate and maintain. Chemical dust control programs can be very effective. However, if applied incorrectly, they can have detrimental effect on mineral recovery. Thus, many operations utilize a combination of baghouses and water, often with limited success.Recent advancements in surfactant and polymer chemistry have resulted in substantially improved chemical dust suppression programs. These products range from non-corrosive surfactant/humectant combinations for road dust control to foam-based systems for crushers and transfer points, to advanced polymers for pile binding and soil stabilization. These advances are discussed in detail, citing results from fieldwork in the precious and base metals industries.INTRODUCTIONThe global nature of the mineral processing industry presents a unique set of challenges. Traditional thinking would tell us what works in one place should work in another. This could not be further from the truth in the area of dust control. We learn very quickly that there are a number of factors that can affect the efficiency and success of a dust control program and that these factors are not all chemical or equipment related. Some of these factors include facility maintenance, product selection, water quality and characteristics, and economic considerations.What has been learned from past experience is that each mineral processing plant presents a unique set of factors that will affect the ability to create an optimal dust control program. This paper presents a myriad of treatment options that will highlight the advancements in chemical dust suppression products and equipment."

Jan 1, 2004

By H. C. Cooke

THE gold mining industry, in Canada as in other countries, has passed through trying times in the past year. The strains and stresses of war have drawn away much of its man-power, both from the labour and the management. The urgent needs of the war machine have greatly curtailed the amounts of steel and explosives that can be allotted to the mines; and the loss, by enemy action, of supplies of such essential things as rubber, bids fair to reduce operations still further, if not cripple them entirely in time. And, as if these difficulties were not enough, war on the psychological front has been declared on the gold mines. Earnest supporters of the war effort, well-meaning theorists, and perhaps others whose intent is less disinterested, have all combined to clamour against the continuance of gold mining. We have been asked, what is the use of taking gold out of one hole in Canada to put it into another in Kentucky. We have been assured that gold will never again have any value, except for filling teeth. We have been repeatedly adjured to look at Germany, how well it has got along without gold. We have been told that it is unthinkable, when this nation is girding her loins for war, that labour and materials should be diverted to this useless effort. Gold miners should be diverted to the base-metal mines, where they can produce something of real value to the war effort; or to war factories; or, in fact, almost anywhere, so long as they are got out of the gold mines. And, what has made the situation even more disturbing, it has seemed as if all this clamour might be convincing governments. In fact, as you all know, the government of the United States did actually take the step of ordering its gold mines to cease operations. Fortunately, however, for Canada, the facts that no large favourable effects resulted from that action, and that, in Canada, gold mining is a much larger part of the national economy than in the United States, have caused our government, so far at least, to avoid this drastic step. In talking about this, however, let me emphasize that I have no more inside information on the subject than any of you. Like Will Rogers, all I know is what I see in the papers.

Jan 1, 1943

By P. A. Riveros, J. Binvignat, V. M. McNamara, D. Koren

The recovery of cyanide from a gold mill solution containing high levels of copper (400 mg/L to 900 mg/L) using the AVR process was evaluated. It was determined that acidification to pH 2 to 3 provides a suitable balance between HCN generation, copper precipitation and acid consumption. A short pilot plant campaign showed that ~75% of the feed WAD cyanide was recovered while the remainder precipitated along with copper upon acidification. The acid consumption averaged 3.5 g H2SO4 per litre of solution. The copper precipitate, consisting mostly of CuCN and CuSCN, was readily separated from the solution by gravity. The volatilization of HCN in countercurrent packed columns averaged 98.7% efficiency. Reabsorption of HCN was practically 100% in NaOH solutions and slightly lower in a lime slurry. Basic volatilizer design parameters applicable to a large-scale operation were determined, including the Henry’s Law constant and the mass transfer coefficient of HCN gas.

Jan 1, 1998

By J. Duncan Keppie

"Auriferous quartz veins occupy zones of dilation. Foldgenerated dilation zones are systematically distributed and are dependent upon the folding mechanism. Comparison of natural and theoretical folds indicates that different mechanisms operated in the Halifax and Goldenville formations.In the slates of the Halifax Formation, the folds are of similar type and internal strain is most intense in the limbs. This internal strain is probably accommodated with little or no dilation.In the meta-sandstone and slates of the Goldenville Formation, a combined flexural and tangential longitudinal strain mechanism, modified by pure strain, produced the folds. Tension fissures produced by this mechanism are: (a) saddle 1'eef veins in slate horizons, (b) veins normal to bedding in meta-sandstone layers in the fold hinges,(c) veins along faults in the cores of tight fold hinges and (d) zones of en- échelon veins in slate honzons in the limbs of folds. Because veins in fold hinges (a, b and c above) account for most of the gold production in the Meguma Group, other factors controlling the distribution and size of these veins are summarized below.1. The size of saddle reef veins is controlled by the curvature of the fold hinge. Thus, a Curvature Index greater than 600 degrees indicates a promising prospect, where"

Jan 1, 1976

By D. K. Uko

In the stretch-bend or bending-under-tension test, a strip is rigidly clamped and restrained at each end and bent by central transverse loading using a radiused punch: The strip deflection at failure has been used as a measure of formability for high-strength low-alloy (HSLA) steels by other investigators. In this work, a detailed study is made of strains developing during stretch bending of an 80,000-lbf/ in 2 (552 MPa) yield stress steel using different punch radii. It is shown that toward the end of the process, the bending strains at both the inner and outer surfaces are tensile and suddenly increase at a rapid and approximately equal rate. The strain ratio in the failure region departs significantly from plane strain , even using a large width-to-thickness ratio of about 10. The effective fracture strains appear to be independent of bend ratio (punch radius/thickness) and significantly below the fracture s train in simple tension. Metallographic and tensile data were obtained for the subject material and, for one bend ratio, the effects on stretch-bend parameters of annealing both on this material and a. carbon steel were compared.

Jan 1, 1977

By M. H. Attia

The concept of sustainable development has been evolved into a working framework for sustainable manufacturing, in which the environmental requirements are introduced into product development at the design stage. This keynote paper is discussing a number of issues pertaining to the impact of manufacturing on the environment. The conflicting requirements of sustainable development, sustainable manufacturing (SM) and economical growth are presented in the light of successful case studies that were able to convert conflicts into opportunities. Integration of SM into the product life cycle is also presented. A number of concepts that are related to Ecoefficiency, e.g., inverse manufacturing, demanufacturing and re-manufacturing are also discussed. The paper underlines the fact that the positive impact of this new philosophy is equally applicable and beneficial to both; developed and developing countries. The paper concludes with an overview of Global trends in environmentally benign manufacturing (EBM); e.g., product-take back and emerging material and processing technologies. The state-of-the-art approach to Life Cycle Impact Assessment and integration of design for the environment DfE principles are demonstrated through some case study.

Jan 1, 2006

By M. J. H. Ruscoe

"The circulation wear rates of pure nickel, cupronickel and nickel-plated-steel coins were measured and found to be in the ratio 1:3:1 . The relative wear rates of nickel and cupronickel coins were similar to those reported in earlier studies, and the circulation wear data for nickel were used as a reference in laboratory wear tests. A correlation between circulation wear rates and laboratory wear rates formed the basis for a prediction of service life using relief legibility as an 'end of life' criterion. This criterion was determined to be an average surface thickness loss of 12 um. The surf aces of nickel and Nickel-Banded-Steel (N-B-STM) coins were observed to harden both in circulation and in the laboratory tests at a rate of approximately I VHN/year of actual or simulated service life. It was also observed that the laboratory wear rate of N-B -S coins increased as nickel cladding thickness increased and this effect was attributed to differences in surface hardness.Wear test results are also reported for the new Canadian dollar coin material which shows a better wear resistance than pure nickel. IntroductionThe subject of coinage wear has a long history, and a number of studies have been published, concerned both with the measurement of circulation wear rates and with accelerated laboratory tests to simulate the behaviour of coinage materials in service. As early as 1803, wear tests were conducted by Hatchett on gold coinage using various types of vibratory and tumbling machines». These tests were commissioned by King George III of England who was concerned about the wear of gold coins in circulation.Early in this century, Adrian performed laboratory tests that showed that the wear rates of cupronickel 75/25 and nickel coins were in the ratio 3:1 and this ratio was later confirmed in laboratory tests reported by Daeppen and Zurrerw, The latter authors also weighed cupronickel and nickel coins that had been in circulation for various times and observed the same 3: I ratio. There was further support from Tylczak and Blickensderfer who reported significantly higher abrasive wear rates for cupronickel compared to nickel, when rubbed against sand paper."

Jan 1, 1988

By K. Ramji

"The development curve in the extractive sector has become longer, steeper, and riskier due to increased social, legal, and political risks from various stakeholders. Indigenous peoples are a unique stakeholder because their growing legal rights to lands and resources can often determine a project’s outcome. A project will only be successful if it is able to obtain the legal permits, withstand any judicial reviews, and gain and maintain the social license to operate. Stakeholder identification, management, and engagement are key risk-mitigation tools required to successfully convert risks into opportunities.RÉSUMÉ La courbe de développement du secteur de l’extraction s’est allongée, elle est devenue plus abrupte et plus hasardeuse en raison de l’accroissement des risques sociaux, légaux et politiques venant des divers intervenants. Les peuples autochtones sont des intervenants uniques puisque leurs droits légaux croissants sur les terres et les ressources déterminent souvent ce qu’il adviendra d’un projet. Un projet ne pourra réussir que s’il est capable d’obtenir les permis légaux, passer à travers les analyses judiciaires, puis obtenir et maintenir le permis social d’exploitation. L’identification des intervenants, la direction et l’engagement constituent les outils clés de l’atténuation des risques nécessaires pour bien convertir les risques en possibilités."

Jan 1, 2016

By M. C. Harris

The past twenty to thirty years have seen unprecedented research activity aimed at understanding the performance of flotation froths. In 1990, Finch and Dobby coined the term froth recovery factor, Rr, to represent the efficiency of the froth in delivering particles from the pulp-froth interface to the concentrate. Originally defined for flotation columns, Rr has also been found useful in modeling mechanical flotation cells, and a number of techniques, based on quite different approaches, have been developed for measuring the froth recovery in industrial flotation cells. None of these techniques is universally successful. This paper reviews the concept of the froth recovery factor, and the basis of each of the techniques that have been proposed to measure Rr, and examines the reasons for this parameter being so difficult to pin down. Advances in Mineral Processing Science and Technology Proceedings of the 48th Annual Conference of Metallurgists of CIM Sudbury, Ontario, Canada Edited by

Jan 1, 2009

By J. E. Dutrizac, J. B. O'Reilly

"Zinc is a relatively abundant element which occurs as both high-grade sulphide ores {sphalerite ZnS) and oxide ores which the ancients collectively termed ""calamine"" (smithsonite ZnC03 and/ or hemimorphite Zn4Si201(0H)2 - H20 and/ or hydrozincite Zn5(C03) 2(0H)6). Although oxidic zinc is readily reduced by carbon, the process becomes thermodynamically viable only at - 1000°C, and at this temperature the zinc is released as a vapour (B.P. 907°C). Casual cooling of the vapour results in its re-oxidation by excess combustion air or even the carbon monoxide product of the reduction reaction. ZnO + C = C09,, + Zn vapom Only fairly rapid quenching of the zinc vapour and the isolation of the reduction products from the combustion gases will yield metallic zinc; these conditions were not produced deliberately until the advent of distillation technology. Until quite recently, the principal use of zinc was in brass manufacture; galvanized iron was not discovered until the 19th century and zinc casting alloys are a relatively recent invention. As will be seen, brass could be produced without recourse to a pure zinc intermediary, and the discovery of brass preceded that of zinc by many centuries. The purpose of this paper is to outline the discovery and early development of both zinc and brass with special reference to the European scene."

Jan 1, 1999

By P. R. Geoffoy, T. Koulomzine

"The discovery of the Mogador deposit concealed by 100 feet of overburden was the result of combined application of geological reasoning, ground geophysical surveys, studies of glacial float and extensive diamond drilling. The ground was acquired because it lay on the projected intersection of the Manville and Laflamme River faults. Systematic ground prospecting led to discovery of mineralized floats. A first unsuccessful exploration campaign lasted several years and consisted of 137 drill holes.In 1951 the boulder nests were reexamined and an associat'on of the mineralized float with boulders of a granodiorite, unknown in outcrops of the district, was established. Consequently, ground magnetic surveys were extended and re-interpreted, and a large anomaly interpreted as corresponding to a batholith was outlined. The existence of the batholith was immediately confirmed by drilling and the Mogador deposit discovered in third hole of new drilling programme in a zone of fractured volcanics paralleling southern contact of batholith.The Mogador deposit is a complex replacement of silicified volcanics by pyrite, pyrrhotite, sphalerite, chalcopyrite and galena carrying values in silver and gold. A total of 1,230,000 tons has been indicated, most of it now classified as fully developed proven ore."

Jan 1, 1960

By R. Stauffer, S. Lindsay

"Sherritt Gordon Mines Limited utilizes pressure hydro-metallurgical techniques to recover nickel, copper and cobalt from su1phidic concentrates, mattes and various other metal-bearing materials.A brief description of the nickel refinery operation is given. In the nickel refinery process, an ammonia pressure leach is employed to treat the feed materials to dissolve the non-ferrous metals as their respective ammine complexes. The resulting leach solution goes through a series of steps which removes copper as copper sulphide and further purifies the solution prior to nickel precipitation by hydrogen reduction. The reduction end solution, containing the cobalt which was originally present in the leach solution as well as residual nickel, is treated with hydrogen sulphide. The resulting nickel-cobalt sulphide precipitate feeds the soluble cobaltic ammine process, which separates the nickel and cobalt and recovers the cobalt as a pure powder.A detailed description of the cobalt recovery process is given. Included are the various steps, comprising: acid leaching of the mixed sulphides, solution purification, ammine complex formation and cobaltous oxidation, two-stage nickel precipitation, cobalt conversion and reduction. A brief description of cobalt powder handling is included, along with typical physical properties and chemical analyses of the cobalt product. In general, the purpose of this paper is to describe the present plant practices employed in the recovery of cobalt as a by-product of the nickel refinery operations."

Jan 1, 1967

By Vicken Aprahamian

"The Royal Canadian Mint (RCM) operates a gold and silver refining toll operation in Ottawa, Ontario, Canada. The silver refining line is a recent addition and was commissioned in 2005. One source of silver in the refinery is from gold doré which undergoes Miller chlorination before electrorefining to 99.99% cathode gold. Treatment of the Miller salt or silver-copper chloride produced consisted of a 2-stage high temperature reduction process step using soda ash prior to 2005. Copper-rich silver bars were produced and shipped offsite for further refining.The copper-rich bars could not be blended into sufficient high grade silver doré to dilute the copper and allow electrorefining in a silver nitrate medium. A new wet process was developed and commissioned to replace the high temperature reduction and allow removal of bulk copper. Thus upgraded impure silver produced was cast into anode for electrorefining to 99.9% purity silver flake. The 2005 RCM Hydromet Slag process is presented as well as its more current version. In addition, mention is made of a novel processing scenario for the introduction of Miller chlorination silver into the electrorefining circuit."

Jan 1, 2015