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By C. G. Anderson

Industrially proven and applied nitrogen species catalyzed (i.e. NSC) acidic pressure leaching has been utilized to treat a number of ores, concentrates and recycled materials. This versatile technology offers many advantages including low temperatures, low pressures, low capital costs, low operating costs, faster throughput and less costly materials of construction than conventional pressure oxidation. This paper will elucidate the application of this technology for production of gold, silver, palladium, rhodium, zinc, germanium, gallium, cobalt, copper and nickel. Recycled material applications will also be elucidated. In addition, details of an application for treatment of a refractory chalcopyrite copper and gold bearing ore will be presented and pertinent economics discussed.

Jan 1, 2004

By Michael Samis

The real option valuation method is often presented as an alternative to the conventional discounted cash flow (DCF) approach because it is able to recognize additional project value due to the presence of management flexibility. However, these two valuation methods can be separated on a more fundamental level by their differences in risk discounting. Real option valuation applies the risk-adjustment to the source of uncertainty in the cash flow while the DCF method adjusts for risk at the aggregate level of net cash flow. This seemingly small difference is the reason why the real option method is able to differentiate between projects according to each project?s unique risk characteristics while the conventional DCF approach cannot. This paper provides an overview of the real options and DCF valuation frameworks and discusses the differences in risk discounting that exist between the two methods. Using grade-school mathematics, this paper clearly demonstrates how, with real options, a unique project risk discount can be calculated which is directly linked to the project?s unique risk profile. It also highlights why the DCF method fails in this regard and shows why a call to ?increase the Risk-Adjusted Discount Rate? is an incomplete solution at best. Finally, a heap-leach project and satellite reserve development project are valued with both techniques and the difference in investment conclusions is explained in terms of the risk-discounting concepts discussed here.

May 1, 2003

By H. F. Maulson

For the benefit of those who are not familiar with the history of the western Provinces-Manitoba, Saskatchewan, and Alberta-as regards our natural resources, a few words of explanation may be in order before taking up the consideration of the Mines Act of 1930. In 1867, The British North America Act was passed by the Imperial Parliament. That Act, which is our constitution, created a union between the provinces of Nova Scotia, New Brunswick, and Upper and Lower Canada (now known as Ontario and Quebec respectively) under the name of the Dominion of Canada. Provision was made therein for embracing other parts of Canada from time to time. That portion of Canada which today comprises the Provinces of Manitoba, Saskatchewan, and Alberta and the lands to the north of them, was then known as Ruperts Land and the North West Territory. In the year 1670, King Charles II had granted by Letters Patent to Prince Rupert and his associates, known as ?The Governor & Company of Gentlemen Adventurers of England, Trading into Hudson's Bay?, commonly known as the Hudson's Bay Company, the lands and territories therein described, being roughly all the lands adjacent to and west of Hudson's bay; also the gold and silver to be found or discovered therein and other rights as more fully described in said Letters Patent. The land so granted was called 'Ruperts Land'.

Jan 1, 1930

By K. O. J. Sidwell

STRATMAT LIMITED, through its subsidiary, the Strategic Manganese Corporation, controls two adjoining iron-manganese properties five miles west of Woodstock, New Brunswick. One is a staked property of 77 claims traversed by one trunk highway, several secondary roads, and a branch line of the Canadian National railway. The other property, a 20-square-mile Concession immediately to the north-east, is also traversed by an excellent network of roads. Both proper-ties are situated in gently rolling farmland. The deposits were discovered in 1836 by Dr. C. T. Jackson. The first attempt to exploit them was made in 1848 when a blast furnace was erected with a capacity of 7 tons per day. The ore was mined by a series of deep trenches that followed the folds of the enclosing slates. In the late years of operation, bog iron ore from Burton and Maugerville, in Sunbury county, was used in conjunction with the Wood-stock ore. An additional 5-ton furnace was erected in 1863 and mining was carried on intermittently until 1884. No further extensive work was done until 1953. During the period of activity, approximately 70,-000 tons of ore are said to have been smelted ( 1). During these earl y operations the Iron Ore Hill and Moody Hill deposits were partially opened, with the ?bulk of the furnace feed being mined from the Iron Ore Hill workings. The low tenor and apparently limited extent of the deposits, the high. ?content of phosphorus, and the increasing scarcity of fuel, were the chief factors that brought the enterprise to an end.

Jan 1, 1957

By Gonzalo Mato, Colin Godwin, G. Ditson

"The mid-Cretaceous Seagull batholith intruded Mississippian sedimentary and volcanic rocks and Jurassic(?) granitic and ultramafic rocks within the Omineca Crystalline Belt in the Yuk on Territory near the British Columbia boundary. Leucoerotic fluorine- and boron-rich granites of the batholith exhibit many textural variations from aplite to pegmatite, but are dominated by a coarse-grained seriate unit and a fine-grained porphyritic unit.Four distinctive tin vein occurrences within and near the batholith are described, the most interesting of which is the MC showing of quartz-calcite-chlorite-cassiterite veins in intensely fractured zones of sedimentary and volcanic rocks. Three other showings occur within the batholith:J) the EC showing of quartz-fluorite-cassiterite-sulphide veins with prominent muscovite-illite alteration;2) the DU showing of quartz-hematite-fluorite-sulphide- sulphide-cassiterite with considerable manganese staining and sericitic alteration; and3) the VAL showing of quartz-tourmaline-cassiterite-fluorite-arsenopyrite veins with little associated alteration.Most cassiterite occurrences are within easterly-trending, vertical structures and all occurrences are thought to represent parts of a single system. These mineralogical and physical variations are apparently related to the distance from the upper contact of the batholith.For the Seagull batholith, Rb-Sr isotopic data give a 100±1.4 Ma isochron age that is concordant with the K-Ar model age from biotite of 101±4 Ma. Initial Sr isotopic ratios for the batholith are high at 0.712, indicating an old, sialic crustal source for this pluton. This initial ratio is similar to values for granitic rocks associated with tungsten deposits in the Yukon Territory. The high initial ratio for Sr, the high Si02 content, the high s/I index, the presence of normative corundum. leucogranitic composition and associated lithophile-tungsten mineralization demonstrate that the Seagull batholith is probably an S-type granitic body. This factor is significant to regional exploration jar tin and tungsten in the Canadian Cordillera."

Jan 1, 1983

By P. Mottahed, E. K. S. Passaris, J. Q. Ran

"The jointed roof of underground mine openings in stratified rock can be analyzed in terms of a voussoir beam. Because of the essential indeterminacy of the structure, previous attempts of theoretically solving the equilibrium equation have been unsuccessful. Numericalanalysisby the finite element method taking the geometrical and joint non-linearity into consideration combined with the experimental method has been adopted to study the performance isopara of the voussoir beam. Deformation and failure mechanism is analyzed in relation to the failure modes. Equations are proposed to estimate the elastic buckling strength and the crushing strength of the voussoir beam and to verify the failure mode of shear sliding. For application of the mechanism of the voussoir beam in mining operations, methods are described to predict the stability of a jointed roof and to design the dimensions of mining openings.IntroductionThe roof stability of an underground mine opening has direct effects on the selection of support methods, opening dimensions and, more importantly, on the safety of mining personnel. The prediction of the roof stability can be of importance in the design of a mining method and in mining operations. The jointed roof of mine openings in stratified rock can be stable under transverse load depending on the roof geometry and properties of the roof material and joints. The stability of this type of roof can be analyzed in terms of a voussoir beam which was introduced by Evans (1941) to study the strength of underground strata. Brady and Brown (1985) analyzed the voussoir beam and suggested that the mechanism of the voussoir beam could be used in the design of underground mine openings in stratified rock instead of the traditional continuous beam theory."

Jan 1, 1993

By J. Erik Scheel

Overview ? About Hard Creek Nickel ? Turnagain property ? Proposed power line ? Recent Preliminary Assessment ? Favourable economics ? Property Geology ? Mineralization and metallurgical characteristics of major lithologies ? Development of the acNi (ammonimum-citrate H2O2) technique ? Overview of necessary steps ? Results of the technique ? Conclusions

May 1, 2008

By Jean-Yve Tremblay, Michel Prud'homme

"IntroductionIndustrial minerals include a group of more than fifty minerals which are marketed into almost all the sectors of industry; they are the backbone of many manufacturing industries. Table I shows major end-uses for industrial minerals in manufacturing sectors.At Energy, Mines and Resources, industrial minerals are divided in three major categories: (I) agro chemicals and chemicals, (2) construction mineral s, and (3) ceramics and specialty minerals. A listing of the major groups of minerals is shown in Table 2.Agro-chemicals and chemicals are sold on the basis of their chemical content and purity. Construction minerals or structural minerals are distinguished by their performance as low cost and bulky commodities. Ceramics and specialty minerals are performance-specific and are sold for their property on imparting functions on end-products. Industrial minerals have unique characteristics that are useful in many stages of processing; from crushed size to micronized fillers a single mineral ca n serve a broad range of industries because of its intrinsic properties.The Industrial Minerals Industry in CanadaCanada has a large industrial minerals base and is a world leader in the production of some of them. The total value of product ion of these minerals has grown by 115% over the last 10 years despite the misfortune of asbestos.Industrial minerals have shown remarkable growth in the past 20 years at an average annual rate of 9.2%, compared to 7.8% for metallic minerals. In 1986, the value of industrial minerals rose to $4.9 billion, or 14% share of the Canadian mineral production. Figure I shows the value of production of the mineral industry for the period 1966-1986.The leading segment in industrial minerals segment since 1976 is the chemicals and agro-chemicals sector which has an average annual growth rate of 5.75 % in terms of value of production. During the same period, the growth rate for the whole Canadian mining industry was 1.37% per annum. The chemicals and agro-chemical s sector increased its contribution to the total value of production of 2% to 6070 despite the growing share of fuel minerals with 59%."

Jan 1, 1988

By John I. Sharpe

Masses of pyritic copper and zinc ores are entrapped along the contact zone between two volcanic groups in the Matagami area. The upper limits of the sulphide concentrations tend to form concordant contacts against lava or cherty tuffite units of the younger group; the lower extremities tend to either follow transverse structures or merge with zones of dispersed sulphides. The sulphides are deformed and intruded by folded dykes. Close relations between metallization boundaries and volcanic lithology and stratigraphy, and a preliminary investigation of the fabrics and crystallization temperatures of the sulphide masses, suggest that the copper and zinc (but; not necessarily all the iron sulphides) were emplaced at h1gh temperatures during volcanism in near-surface lithological-stratigraphic traps. Introduction T HE Matagami area is centered 120 miles north of the Val d'Or and Noranda camps in north-western Quebec. For the present purpose, it is considered to comprise a 155-square-mile area in Isle-Dieu, Galinee and Daniel townships which encompasses the main sulphide masses. Airborne geophysical surveys within this area in 1956 led to the discovery of a large sulphide body -the.

Jan 1, 1965

By B. Ignasiak

Laboratory studies suggest that improvements of coke strength brought about by pre-heating caking coals before carbonization accrue from inadvertent oxidation rather than from other low-temperature changes in the coal mass. Controlled oxidation of highly caking coal, followed by laboratory carbonization, produces cokes which, in terms of a laboratory scale tumble test index, are equivalent to those obtained from prime metallurgical blends. Appropriately formulated blends of exhaustively oxidized and fresh caking coal similarly yield cokes with strength indices comparable to those of cokes made from the same coal after oxidation under optimum conditions.

Jan 1, 1979

By R. L. Stanton

"The present contribution is complementary with a preceding one on the field association of the conform-able ""pyritic"" deposits. It considers the more important features of their mineralogical constitution and their microtextures, re-examines the present interpretations of these, and of-fer-some alternative explanations. The term ""pyritic"" for these de-posits is m many cases a misnomer, as two quite distinct ore types are inuolve. One is a banded pyritic sphalerite-galena-chalcopyrite ore (for which the term '•pyritic"" is in-deed quite suitable), while the other is non-banded and is composed essentially of pyrrhotite and chalcopyrite. In addition to these constitutional differences, each is distinctive in general appearance and texture. The occurrence of two such consistent but clearly distinguishable ore types is attributed -rather than to difference in source material and pressure-temperature conditions of deposition -to the contribution of similar source material to dissimilarly oxygenated environments of sedimentation. Textures in the banded ores generally thought to be indicative of replacement or of high-temperature exsolution are explained by slow, law-temperature segregation in situ during compaction, folding, and regional metamorphism."

Jan 1, 1960

Forward-Looking Statements Information set forth in this presentation may involve forward-looking statements under applicable securities laws. Forward looking statements are statements that relate to future, not past, events. In this context, forward-looking statements often address expected future business and financial performance, and often contain words such as "anticipate", "believe", "plan", "estimate", "expect", and "intend", statements that an action or event "may", "might", "could", "should", or "will" be taken or occur, or other similar expressions. Forward-looking statements or information relate to, among other things expected iron ore demand, timing for a production decision, expected share price drivers, potential railway options, timing, grade and quantity of potential resource estimates, employment and economic benefits, taxation estimates and timing of key project milestones. By their nature, forward-looking statements involve known and unknown risks, uncertainties and other factors which may cause our actual results, performance or achievements, or other future events, to be materially different from any future results, performance or achievements expressed or implied by such forward-looking statements. Such factors include, among others, the following risks: the risks associated with the need for additional financing; operational risks associated with exploration; fluctuations in commodity prices; title matters; environmental liability claims and insurance; reliance on key personnel and other risks and uncertainties discussed in the management discussion and analysis section of our interim and most recent annual financial statement or other reports and filings with the TSX Venture Exchange and applicable Canadian securities regulations. Forward-looking statements are made based on management's beliefs, estimates and opinions on the date that statements are made and the Company undertakes no obligation to update forward-looking statements if these beliefs, estimates and opinions or other circumstances should change, except as required by law. Investors are cautioned against attributing undue certainty to forward-looking statements. NI 43-101 Qualified Person Alderon?s exploration work on the Kami Project is supervised by Edward Lyons, P.Geo., the Chief Geologist for Alderon and a Qualified Person as defined byNational Instrument 43-101. Mr. Lyons has reviewed and is responsible for the technical information contained in this presentation. Mr. Lyons is a member in good standing of the Association of Professional Engineers and Geoscientists of British Columbia (APEGBC) and the Professional Engineers & Geoscientists Newfoundland & Labrador (PEGNL) as a registered Professional Geoscientist (P.Geo.).

May 1, 2011

By D. J. McLaren

"Arctic Canada is one of the largest undeveloped terrains remaining in the world, and is in many ways unique. The ecological balance of the region is more delicate than tropical or temperate regions of similar size. This region is likely to be developed by research for and production of resources, primarily petroleum, in the immediate future. As well as sensitive terrain surface caused by permafrost in some areas, many large and small mammals and birds are also in a delicate balance with the environment. Small changes in this balance can have large effects.The probability of finding petroleum in different regions varies widely, but already there are good indications on the mainland and in the Islands that both oil and gas are present. Geophysical work in the offshore, particularly the Beaufort Sea, suggests further promising potential. Possible reserves in the Islands and mainland Arctic may amount to 50 or more billion barrels.A responsible approach to problems facing exploitation in an Arctic environment includes the careful monitoring by industry of likely effects of their activities. The Mackenzie Valley Pipeline Research Association test loop at Inuvik provides an example of such monitoring. Outside Canada, the operations at Prudhoe Bay on the north coast of Alaska show how major companies may operate responsibly and reduce environmental interference to a minim'.::at. Nevertheless, four variables must affect any decisions to be made concerning energy resource exploitation in the Arctic. These are man's need for energy, economic and industrial pressures to develop energy sources, the desire to preserve a deteriorating environment, and the role of government as representing all individuals in the country and their several points of view. Factors that must be taken into account in making any decisions include the importance of Canadian oil in a world picture, the need for alternative sources of energy in the near future, the depletion of nonrenewable resources at an accelerating rate and the increasing awareness that the major problems facing man have no direct technical solution and that social or political decisions must precede further techno-logical development."

Jan 1, 1971

By Suzanne Paradis

Geographic distribution ? Deposit economics ? Temporal distribution ? Tectonic settings ? Basin architecture ? Morphology ? Ore-fluid chemistries Key exploration criteria

May 1, 2006

By T. R. Yu, D. B. Counter

"In an effort to increase productivity, the use of fly ash as a binder for consolidated backfill was studied. From laboratory and underground tests f or its cementitious properties and environmental effects, it was found that a portion of Portland cement could be replaced by the same amount of type ""C"" fly ash to produce an acceptable consolidated rockfill product for use at Kidd Creek.The environmental concerns in terms of dust control and emanation of radon gas were unfounded from measurements. The dust count was comparable to the use of Portland cement only, or with ground blast furnace slag, and the radiation readings were low, averaging one-seventh the regulation level.Since May 1984, a total of over 100 000tonnes of fly ash has been consumed as a binder blended with Portland cement, producing over four million tonnes of consolidated rockfill. To date, the fill in the stopes has performed very satisfactorily, while yielding considerable cost savings.IntroductionThe Kidd Creek minesite, located 27 km north of the city centre of Timmins, Ontario, produces 4.5 million tonnes of base metal sulphide ore annually. The mining method for both No. I and No .2 mines is mainly sub-level blasthole stoping with delayed backfilling.No. 1 mine was developed with a shaft to a depth of 930 m in 1973 to recover the ore between the floor of the open pit at the 216 m horizon, and the 792 m horizon. Stopes are normally 18 m wide, 22 m to 65 m long, with heights varying from 90 m to 135 m. Vertical rib pillars between stopes are typically 24 m wide and sill pillars are 30 m thick.Pillar recovery is implemented after the consolidated rockfill placed in the mined stopes has cured for a period of at least three months. This allows a maximum recovery of the ore with a minimum of dilution, while also maintaining safe working conditions.No. 2 mine was developed from a second shaft, sunk to a depth of 1530 m in 1978, for the recovery of ore beneath the No. I mine. Sub-level stoping in No .2 mine is similar to No.1 mine in methodology, yet differs in sequencing, as no rib pillars are left."

Jan 1, 1988

By D. Pawelus, J. Butra, R. Debkowski, M. Szpak

Impact of horizontal stresses on stability of underground workings in mines is a very important issue in underground mining. Identification of the initial state of stress in the rock-mass should be one of the main actions taken into account while designing and carrying out the mining activity in underground mines. The paper presents the tests on three dimensional stress pattern in Polish copper mines, owned by KGHM Polska Miedz S.A. Group, carried out in 2012. The research program covered 7 measuring stands in two mines; their average depth was about 1000 m. The main aim was to identify the values and directions of horizontal stresses in order to optimize the extraction and to improve the safety. The overcoring method with the use of CSIRO HI type probe was applied. The paper also describes the measuring technique which was developed for the purpose of specific mining and geological conditions of KGHM mines, taking into consideration the natural hazards encountered there as well as technical and operational capabilities with regard to drilling equipment. The experience gained during the underground measurements and the issue of making such measurements in underground copper mines in Poland are presented in the paper. The stress patterns obtained during the underground measurements are of application importance for the process of designing the spacing of mine workings and improving their stability and mine support selection.

Jan 1, 2015

"A 3-dimensional finite element model for stress/stability analysis of rock excavations in underground mines is presented. Developed for use on personal computer under OS/2 operating system, the model employs the 8-node isoparametric brick element and accounts for such loading conditions as in situ stresses and gravity loading of the rock mass. In addition, modelling of backfill in mine stopes as in situ stress-free material is incorporated. Material failure is assessed by Mohr-Coulomb or Hoek-Brown failure criterion. A mine design example is presented to illustrate the potential use of the model as a tool for stope design.IntroductionNumerical modelling of mine structures has become a vital tool for mine design in recent years. The need to maximize ore extraction ratio and to reach deeper mineral deposits underground has led the mining industry to employ numerical methods of analysis to undertake complex ground control studies in order to better understand the ground response to mining excavations and to evaluate the ground support requirements. Thanks to the rapid developments in computer technology, it is now possible to perform very comprehensive analyses including, but not limited to, 3-dimensional, elasto-plastic, or large deformation or time dependent nonlinear analyses on personal computer.During the past ten years or so, many researchers undertook 3-D finite element analyses of rock mechanics problems in mining engineering. The following is only a sample review. For example, Chan'!' used three-dimensional finite elements to study the mechanical response of jointed granite during shaft sinking at the Canadian Underground Research Laboratory. Wang et al.(2) performed 2-D and 3-D finite element analyses of room-and-pillar mining system with flat and rolling coal seams. Thatejatu used three-dimensional finite element method to examine the problem of branching tunnels. Dolezalovaw used three-dimensional finite elements for the analysis of tunnel-face advance with partial excavation as well as full-face excavation in combination with rein for cement of the face by long anchors. Peili (5) used three-dimensional finite elements for the simulation of rock-liner interaction near the tunnel face."

Jan 1, 1992

By J. R. D. Gravel, D. A. Poland

"The induration of iron ore pellets has always utilized prefired pellets to protect the pallet cars from the environment of the induration furnace. This paper presents the process used to obtain superior upper sidewalls. These heat resistant castings are used on induration pallet cars, and their life improvements by as much as 400% is a significant step towards the reduction of the prefired (or hearth layer pellets.) The benefit to the industry in the removal of the hearth layer is improved overall productivity. IntroductionThe Iron Ore Company of Canada (IOC) operates with production facilities located in Labrador City, Newfoundland and Sept Iles, Quebec. It has recently been acquired by North Limited, an Australian based resource oriented company. Prior to its acquisition, IOC has examined several methods of operational cost reductions. One of these was an examination of indurrating pallets. Pallets are composed of numerous assemblies and sub-assemblies. The examination of the upper sidewalls began as an intent to increase the operational life of the component. The anticipated net effect was to be a reduction in the overall pallet maintenance cost. All of the components and assemblies have undergone a severe scrutiny. IOC has found that the success of the project has depended upon not only the technical competency of all parties involved, but also upon the ability to share risk, to be innovative, and to find a partner with whom the development can proceed without fear and yet with accountability. IOC has found in Cast Steel Products (CSP) such a partner in the field of pallet development. This paper will undertake to explore the progression into the arena of partnering between IOC and CSP. CSP and IOC met in the fall of 1994. The work of re-engineering the pallets began with an initial order for 36 pallets in March, 1995. The work on the upper sidewalls involved segregation of the effect of alloy development versus physical geometry development. The nature of partnering between the two companies allocated alloy development to IOC and physical geometry development to CSP, yet no advancements were made in either area without the close co-operation or the involvement of both partners."

Jan 1, 1999

By Bertrand Wolfman, William E. Stanley

"This paper reviews the traditional mine accounting systems, including ""custodial accounting"" and unit costing, and then suggests that the use of flexible budgets represents a more suitable method of reporting costs in order to assist the mine manager in improving productivity. Examples of various applications are given to show that the result is a clear reporting structure.Custodial Accounting is Emphasized in Traditional SystemsTraditional mine accounting has been mainly concerned with the accuracy of financial reporting to ""head office"" for the use of the directors and the company's bankers and shareholders. This is often called custodial accounting and it represented the main purpose of accounting when first developed in Europe hundreds of years ago. This important development permitted the establishment of enterprises which were separated from their owners because they could rely on accurate financial reports of management's stewardship.As custodial accounting is fairly broad and historical in nature, it is often not very useful to the mine manager for ongoing monitoring of performance of mining, milling, maintenance, and other support and staff groups. In spite of the considerable investment in accounting staff and computer support, many accounting systems have not been upgraded so that they accurately reflect workplace performance on a weekly or monthly basis.Budgets are Often FixedMany mines today also still emphasize fixed budgets. Thus, the mine plan which is set in the fall of one year is converted to a monthly tonnage and detailed dollar budget for periods of up to sixteen months in the future. The only certainty in this plan is that actual events will differ; timing, mix of mining methods and production volumes will differ on a monthly basis.Unfortunately, the fixed budget has no capability to reflect these operational changes. It is frozen for the full year. The result is that actual results will inevitably be compared to an outdated target."

Jan 1, 1982

By S. Zador

"IntroductionIn the past decade, metallurgical and mining companies have shown an increased interest in the licensing of technology. When licensing technology, it is usually to the benefit of the parties, to have at least some of the technology to be licensed protected by a patent.This paper is intended to bridge the gap between the engineer in the field of mining, metallurgy and mineral processing who is interested in exploiting an invention commercially, and the patent agent or intellectual property lawyer whom he/she might retain to prepare a patent application and then prosecute the application to obtain a granted patent. It is also intended to encourage the inventor or a small business concern to consider the value of patents in the sale and licensing of technology. The lawyer may subsequently advise and assist the inventor in licensing his/her invention.A brief outline of some of the basic features of the patent system follows. The nature of the information, which the patent professional requires from the inventor to enable him/her to draft a patent application, will also be considered in general terms. Furthermore, various types of licenses which may be drawn up between a licensor of specific technical information and a licensee, will be listed and briefly discussed. No attempt, however, will be made to give a comprehensive and detailed account of the above aspects; the interested reader should consult legal publication and reference books, and patent professionals for further specific information.A granted patent is a document which describes an invention and how to practise it. The claims of the granted patent, figuratively speaking, fence off the intellectual property the inventor regards as his invention. The Commissioner of Patents, representing the Government, grants to the inventor or his assignee the exclusive right of making, constructing and using the invention, and selling it to others to be used, for a limited period of time, in exchange for disclosing the invention to the public. Thus, a patent prevents others from practising the claimed invention but it does not, necessarily, bestow the right to the patentee to practise his own invention. The term of a patent now in Canada and in most of the developed countries of the world, is 20 years from the date of filing the patent application. In the United States the patent term is still 17 years from the date of issuance of the patent. In Canada, the term was changed to 20 years in the new Canadian Patent Act which came into force on October 2, 1989. Any patent application filed prior to that date or granted before it, retains a 17 year life, commencing at the time of grant."

Jan 1, 1991