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By C. R. van Staal, L. R. Fyffe, J. A. Winchester

"The geochemical characteristics of Early Paleozoic volcanic rocks are used to establish the following tectono-volcanic regimes in the northeastern mainland Appalachians: foreland continental rift volcanics; fore-arc ophiolites; island-arc volcanics; back-arc ophiolites; and back-arc ensialic volcanics. A Late Precambrian calc-alkaline magmatic arc bounds the Early Paleozoic volcanics to the southeast.The Precambrian calc-alkaline volcanics of the Caledonian Highlands, primitive Cambro-Ordovician oceanic-arc volcanics of the Eastern Townships, and within-plate Ordovician volcanics of the Miramichi Highlands can be related to a progressive change in mode of subduction from compressional Andean-type in the Late Proterozoic to extensional Western Pacific-type in the Early Paleozoic. The development of marginal oceanic basins in the Paleozoic created a more favourable environment for volcanogenic sulphide deposition, particularly in back-arc areas.The influence of tectonic setting is reflected in the distribution, size and metal ratios of the massive sulphide deposits associated with the volcanic rocks; deposits within intra-oceanic arcs in the Eastern Townships of Quebec average two million tonnes grading 2.2% Cu, 4.0% Zn, and 0.6% Pb, whereas those within a back-arc, ensialic rift near Bathurst, New Brunswick, average nine million tonnes grading 0.6% Cu, 5.4% Zn, and 2.2% Pb."

Jan 1, 1990

By C. S. R. Rondestvedt

In February 2010, Teck?s newest Concentrator at Mina Carmen de Andacollo (CDA), Andacollo, Chile was commissioned. The Concentrator is a single line configuration, comprising of one 36 ft diameter x 20 ft long SAG mill driven by an 18,000 hp gearless drive. The SAG mill feeds two ball mills each 25 ft in diameter x 40.5 ft long, each driven by a total of 19,000 hp through dual pinion drives. A series of four phases will be reviewed from operational readiness, mechanical completion, commissioning, and ramp-up. Also, now after 6 months of operation, this paper will review the significant steps taken during ramp-up enabling the announcement of commercial production, in October 2010.

Jan 1, 2012

By N. E. Izatt

Molecular recognition technology (MRT) has a wide range of applications in the hydrometallurgical and chemical processing industries for the selective removal of iron as well as various other impurities from a variety of streams, including aqueous solutions through a wide pH range, as well as organic solutions. An example of a commercial application is provided for the removal of iron from an aluminum chlorohydrate stream. In this example, MRT has a selectivity for iron relative to aluminum which is significantly higher than that of ion exchange resins. A discussion of MRT capabilities for other impurities and streams is also provided.

Jan 1, 2006

By Alan Bauer

New developments in drilling, blasting and explosives in both open-pit and underground mining operations are discussed, as well as novel surface blasting techniques such as are used in tar sand mining.

Jan 1, 1978

By J. Lui

At its Copper Cliff Smelter, bulk nickel and copper concentrate is processed in two Inca flash furnaces and Peirce Smith converters to produce Bessemer matte containing 0.6%Fe. After slow cooling and Matte Separation, Bessemer matte is converted into three main products using magnetic separation and flotation technology: (1) a nickel containing chalcocite concentrate (MK); (2) two types of copper containing nickel sulfide (ME and MR); (3) metallics (MYN). MK is further processed in the Inca top blowing bottom stirring MK Reactor to produce semi-blister copper containing ~4%Ni and ~3±1 %S. The semi-blister copper is then purified in the multi-purpose vessels (MPV) to produce blister copper by reducing Ni, Fe and S content through oxidation. High melting point NiO is formed inside the MPVs. The accumulation of solid NiO and other oxides requires periodic cleaning by adding reductant and furnace matte, a unique process called "washout" at Inca. For many years, the reductant used for the "washout" process has been 15%Si Ferro-silicon. With increasing cost and limited suppliers for 15%FeSi, alternative reductants were pursued. This paper summarizes the development and commercialization of new alternative reductants for MPV "washout".

Jan 1, 2007

By D. C. Brady

"Within six months from award of a project management contract, Les Mines Dumagami Limitée, Cadillac, Quebec, was operating its new hoisting facility. This was accomplished with less than a six-week shutdown of mine production while still maintaining shaft access for underground maintenance.The work involved installing a refurbished /3.5 ft diameter double drum hoist, replacing a timber headframe with a newsteel headframe, increasing the ore bin capacity from 500tons to 1000 tons, constructing a new substation, and upgrading related facilities.This paper describes the work and methods used by various contractors, Les Mines Dumagami Limitée and J.S. Redpath Mining Consultants Limited to bring this project to a successful completion. It discusses the history of the project from proposal stage through to the design, procurement, scheduling, and construction management. The paper also comments on problems that were encountered and the methods used to overcome them.IntroductionThe Donald J. Laronde Mine of Les Mines Dumagami Limitée (Dumagarni), a gold and copper producer, is located in northwestern Quebec, approximately half way between Val d'Or and Rouyn. The mine started production in the spring of 1988 and the first gold bar was poured in June 1988.Following a request by Dumagami, on February 22, 1989, J.S. Redpath Mining Consultants Limited(Redpath) delivered a proposal to increase hoisting capabilities from 1500 tpd to a minimum of 2500tpd. Although various concepts were considered, Redpath proposed a new hoist house along the same shaft axis as the existing hoist, and located on the site of the existing substation. They would then provide a new substation, replace the headframe with a largersteel structure , gain extra storage capacities by increasing the bin heights, and raising the roof of the bin house accordingly.Although underground mining would have to be stopped for a month, the mill production would be maintained by feed from Dumagami's open pit.Figure 1 shows the original plant layout and Figure 2 represents the general arrangement after the project was completed . Table 1 compares the original hoisting facilities to the new facilities.On March 2, Dumagami awarded Redpath a contract that included preliminary engineering, detailed engineering, procurement and contract administration, and later added construction management. The preliminary engineering refined the initialconcept, selected major equipment, and prepared schedules and capital cost estimates for the total project."

Jan 1, 1991

By D. Atkinson

"Porphyry molybdenum-tungsten mineralization on the east flank of Hudson Bay Mountain crops out over 5 km2 and is intersected to depths of 2 km. Features such as a hornblende-biotite aureole, mineralogical zoning and dike, vein and fracture geometries within lithologies of the Middle to Lower Jurassic Hazelton Group and Cretaceous Skeena Group reflect an intrusive complex, the Upper Cretaceous to Early Tertiary Hudson Bay Mountain stock which has been intersected by drill holes. The stock is believed to be the mineralizing agent. A southeast-dipping granodiorite sill has been outlined by drilling within the Hazelton Group. Molybdenite and scheelite veins cut all rock types; however, the granodiorite sill hosts a higher density of fine-grained, banded, quartz-molybdenite and pegmatitic quartz-molybdenite veins reflecting a competency contrast between the intrusive sill and other country rock. Due to the relative abundance of these veins, grade is higher within areas of the sill. Above the 15000£ cross-cut 20.6 million tonnes grading 0.401% MoS2 and 0.041% W03 have been defined. During exploration of the deposit sampling procedures had to be adjusted because of the nugget effect attributed to drill intersections of banded and pegmatitic veins.IntroductionMolybdenite was discovered in outcrop at the foot of Kathlyn Glacier on Hudson Bay Mountain and first reported by the Geological Survey of Canada in 1944. The deposit has several names: Hudson Bay Mountain or Glacier Gulch, both after its location, and Yorke-Hardy after the original staker.The deposit is on the east flank of Hudson Bay Mountain, 9 km northwest of Smithers, west-central British Columbia, within NTS area 93L/14 (54° 49' North, 127° 18' West, Fig. 1). Hudson Bay Mountain, on the southern edge of the Bulkley Valley, is a dominant topographical feature reaching 2590 m elevation. Mineralization is partly overlain by the Kathyln Glacier which is visible from Highway 16. Access to the 3100 m of underground development is from a portal at 1066 m elevation on the east slope of Hudson Bay Mountain."

Jan 1, 1995

By James E. Wennen

The through-put and energy efficiency of an autogenous (AG) grinding mill are adversely affected by variability in rock size and rock competency. This applies to both fully autogenous and semi-autogenous (SAG) grinding circuits. In this paper we focus on an approach to overcome the problem of inconsistent mill through-put related to variability in mill feed size and rock competency. The focus is on ores containing hard, competent rock. This approach consists of preparing feed to an autogenous mill that contains 20% coarse media rock and 80% of material crushed to pass 37 mm. Results of pilot-scale testing for two iron-ores will be presented to show that a 10% to 12% reduction in unit energy consumption is possible with prepared feed, compared with feeding the mill with conventional primary crusher discharge.

Jan 1, 2012

By D. R. Boyle

"The basal type uranium deposits in south central British Columbia occur within unconsolidated, late Miocene fluvial paleochannel sediments that overlie major fault zones within the Okanagan Highlands Intrusive Complex. Prior to the formation of mineralization, paleovalleys containing host sediments were flooded by Pliocene valley basalts of the Plateau Basalt Formation. Five uranium deposits have been outlined to date, of which the Blizzard (4020 tonnes U) and TYee (650 tonnes U) are the largest. The basement intrusive complex underlying the deposits varies in age from early Cretaceous to Eocene and is comprised of quartz monzonite, granodiorite, Coryell monzonite, porphyritic granite and pegmatite.The mineralized host sediments comprise a complex sequence of interfingering conglomerates, arkosic sandstones and mudstones. Organic material is abundant in many, but not all, mineralized beds. Uranium mineralization is present in the form of uranous (ningyoite) or uranyl (saleeite, autunite) phosphates coating clastic grains and filling voids. Because of very strong reducing conditions related to large concentrations of marcasite and organic material, ningyoite is the only uranium mineral in the Tyee deposit, whereas the Blizzard deposit contains a more complex assemblage of minerals (saleeite, autunite, ningyoite). The observed paragenetic sequence of mineral precipitation in the Blizzard deposit (autunite-saleeite-ningyoite) indicates that the uranyl minerals, saleeite and autunite, are primary. Small amounts of Zn, Ni, Co and Mo have been introduced into the Blizzard deposit whereas Mo is the only non ore-forming element enriched in the Tyee deposit. Mn is the only depleted element in both deposits."

Jan 1, 1986

By Matthew S. Hall

Gold/iron oxide catalysts have been prepared and their catalytic performance evaluated for low temperature CO oxidation. The method and temperature used to dry the sample has a significant effect on their catalytic activity. Analysis by TEM revealed the catalysts contained Au particles, although catalysts with high and low activity did not always differ in their microstructure as evidenced by TEM. Catalysts were characterised using XPS and the difference between the Au(4d) and C(1s) binding energies measured; in general the greater the difference, the higher the catalytic activity of the material.

Oct 1, 2003

By P. Curry, H. G. Stephenson, B. Van Den Bussche

"Three Sisters Resorts Inc. currently owns a2035 acre (824 ha) parcel of land, which previously belonged to Canmore Mines Ltd. Approximately 50% of these lands, that are slated for residential, resort and recreation development, have been undermined for coal in one or more seams.Norwest Mine Services has been contracted by the developer to assess and advise them on any past mining activity that may be potentially hazardous to their development and offer solutions to how these hazards may be mitigated or avoided.The following paper deals mainly with the procedures put in place and accepted by the approval authorities, and the Staged approach to the Investigative Procedure that Norwest follows in the mining assessment and mitigation work for Three Sisters."

Jan 1, 1996

By G. W. Neumann, J. R. Schnarr

The lead-zinc-copper-silver ores mined by Brunswick Mining and Smelting Corporation Limited at their No. 12 underground mine and No. 6 open-pit operation, and treated by distinct concentration processes in separate plants, present difficult metallurgical problems because of the extremely fine dissemination of the valuable minerals with pyrite and pyrrhotite. The problem of concentration is further complicated, in the No. 12 ore, by the presence of a varying content of graphitic carbon. This paper describes the milling of No. 12 ore and the production of copper, lead and zinc concentrates by differential flotation.

Jan 1, 1971

By Steven Hart

In September 2009, Newmont began the commissioning of a 3 stage crushing and milling circuit at its Boddington Gold Operation in Western Australia. The Boddington ore has been recognized as one of the hardest and most abrasive ores treated to date and this played a pivotal role in the selection of crushing and HPGR technology for this operation as opposed to the more conventional SABC circuit. This paper will examine the scale up from laboratory to pilot plant and full scale operation of the crushing circuit. There have been many challenges to overcome in the first 18 months of operation; however, the HPGRs have in general met design expectations and performance is expected to improve further with ongoing design changes

Jan 1, 2012

By Grant S. Diamond

THE BIBLIOGRAPHY on the use of static electricity in mineral beneficiation consists largely of patents. Some references are found in mineral textbooks, but very little data on flow-sheets of commercial installations are known to the writer. As a matter of fact there have been relatively few successful commercial applications of importance. Johnson prepared and published a Table showing the polarity and static field intensity requirements of many minerals. There have been reports of successful beneficiation of rutile, zir-con, coal, potassium chloride, and phosphate rock. Otherwise, the field of success has been very limited. This may be due to three reasons: first, the mining industry has been averse to dry processes, be-cause of dust nuisances in dry crushing; second, the electrostatic processes used in the past apparently developed no substantial economic advantages; and third, because flotation or other . methods have proven successful on many minerals, the industry has not felt the need for a radically different process. In the feldspar industry there was ?an attempt at electrostatic beneficiation about twenty years ago which was based on the use of fluoride fuming of the pegmatite head feed, in order to make the mineral reactive in a static field. This process was originally said to be successful, but was discontinued because of corrosion damage to machinery. Another effort by use of a chemical additive such as an or-ganic hydroxyl compound has also been attempted. Neither of these processes is known to be in use today.

Jan 1, 1957

By D. E. Keeley

Introduction Gunite is a mixture of sand and cement applied to any surface by being shot by compressed air through a nozzle, where it is wetted just before leaving the orifice. The mixture is transported through a hose from a machine called a 'cement-gun'(l). Guniting of rock surfaces has been standard practice at the Mcintyre Porcupine Mines, Limited, for several years. Where used on walls and backs of cross-cuts; shaft stations, and other rock openings, as an air seal, gunite has eliminated the necessity of constant scaling to keep rock from falling from these places, and, under worse conditions, it has been used in place of timber supports. This has been of definite help in reducing costs, promoting safety, and minimizing fire hazards. During the past year guniting has been quite extensively used here in the rock head-works of the new internal shaft, No. 12, sunk from the 3,875-foot level. Gunite is at present being applied to the stations of that shaft well below a mile from the surface. This paper describes the method of guniting as carried out at the McIntyre, and illustrates how, by the adoption of this process, mining problems connected with scaling and loose ground have been completely solved. It is hoped that the information presented may stimulate discussion and assist in the use of gunite in this and other mines. The guniting method of applying cement was first developed by Carl E. Akeley (2), Curator of the Field Museum, Chicago, in 1907, and was exhibited in New York at the Cement Show in 1910. The museum was located in one of the old World's Fair buildings, built of roughcast and in bad repair. Mr. Akeley, who was a man of inventive nature, set about devising means of applying cement to repair the walls. The cement-gun was the result. Mr. Akeley was a taxidermist of note, a sculptor, and also the inventor of the Akeley camera. In his work, he was in the habit of using fast setting materials to build up foundations for statues, etc.

Jan 1, 1934

By A G. Rogers

This paper discusses the lubrication of surface and underground mining machinery and equipment from the standpoint of machine components. The machine components considered are bearings, cylinders, gears, chains, couplings, fluid drives, hydraulic systems, screws and wire ropes. The best selection of lubricants for these machine components, and for sub-divisions of the components, are outlined. They form general recommendations, for average operating conditions in both surface and under-ground mining operations. The American Petroleum Institute's service classification of both engine crankcase oils and gear oils is de-scribed and used in recommending products for these applications. The practical aspect of lubrication is kept foremost in the recommendations, which are designed to meet the requirements of a wide variety of equipment with the minimum number of lubricants. THE lubrication of mining machinery and equipment presents a variety of problems peculiar to the industry. The type of mine, the ambient temperature, water, dust, and operating and maintenance practices, as well as the age and condition of the equipment, are variables which have to be considered in making lubricant recommendations.

Jan 1, 1963

By C. S. Gibson

"MOST of the mines in the Province of Ontario in Canada are multi-level operations in steeply dipping veins; yet there is an appreciable number whose de-posits are relatively flat-lying, ranging up to 45° inclination.The veins vary in width up to several hundred feet and may or may not be branching systems. The depths of mines range from a few hundred to 8,000 feet, approximately. The primary products of the underground group are asbestos, gold, silver, cobalt, copper, nickel, iron, uranium, talc, fluorspar, gyp-sum and salt.There are a few open-pit mines. The majority are temporary in type because, as the outcrops are removed, mining is continued be-low surface. Primary products of the open pits are copper, nickel, iron, magnesium and nepheline syenite.The industry as a whole employs about 50,000 persons, approximately 60 per •cent of whom have dust-exposure occupations. The definition of a dust-exposure occupation and the requirements for •dealing with same are set forth in The Mining Act of Ontario.Results of extensive and continuing studies on the incidence and progression of silicosis have been reported periodically for years past, in annual reports of the Mines Accident Prevention Association of Ontario and in papers presented at Conferences sponsored by Mcintyre Research Foundation of Toronto, all of which have been published. The information provided therein proves the effectiveness of the means being used to prevent silicosis and allied disorders."

Jan 1, 1960

By Jr. Jones

This paper is derived from a document that compiles autogenous and semi-autogenous mill installations worldwide, through the end of 2010. Updates have been solicited from all major mill manufacturers and most have responded. A review of AG/SAG mills sold to date and in the last five years indicates that the AG/SAG mill market is very healthy and the trend is larger diameter mills with high diameter-to-length ratios. Ring motors (gearless) are the preferred drives for large mills even though the power transmitted through a gear drive is expected to near 11,000 kW per pinion in the near future.

Jan 1, 2012

By J. M. Cummings

DURING the past year, the writer has investigated the treatment of a variety of British Columbia tungsten-bearing ores. Much of the test-work described in this paper was carried out in collaboration with Mr. A. G. Lyle in association with the British Columbia War Metals Research Board at the University of British Columbia. The remainder was completed in the laboratories of the Department of Mines at Victoria. Two mills in the Province are at present treating tungsten ores. Descriptions of these are included through the co-operation of Messrs. S. Gray (1) and A. A. Almstrom (2). MINERALOGY, OCCURRENCE, AND SPECIFICATIONS In the present paper, attention is directed solely to scheclite, inasmuch as known occurrences of other tungstcn minerals in British Columbia are of mineralogical interest only. The properties of scheclite are listed below: Percent W03 .. 80.6 Tenacity ...... Very brittle Çrystallization Tetragonal Lustre ........ Vitreous to resinous Cleavage ...... Good in 4 directions Magnetism ... Non-magnetic Specifie gravity 6.05 Diaphaneity .. Transparent to translucent Hardness. . . . . . 4.5-5.0 Scheelite may contain as much as ten per cent of molybdenum in solid solution, but most of the specimens from British Columbia examined by the writer were relatively pure.

Jan 1, 1943

By S. Jeon, T. H. Kim

"Understanding the frictional properties of discontinuities is crucial to ensure the stability of underground structures. In particular, the frictional behavior at depth depends on the complex interaction among mechanical, hydrological, thermal and chemical characteristics and their coupled effects. In this study, a series of triaxial compression tests were carried out to investigate the behavior of rough shear surface of synthetic rocks. The frictional behavior showed little variation at different confining and water pressures. The test results were analyzed using Coulomb’s failure criterion. In addition, numerical analysis was carried out using PFC2D to simulate the test.INTRODUCTIONUnderstanding coupled behavior of rock at depth is of great importance in design, construction and operation of underground structures such as a disposal facility of radioactive waste, hot dry rock geothermal system and oil reservoir. In particular, many uncertainties are involved in characterizing deep rock mass deformation in the designing process and interactions among fluid flow of groundwater, high temperature and stress disturbance should be considered. Many independent studies have been carried out to investigate the thermal, hydro, mechanical and chemical coupled effects in numerical and experimental methods. They include the researches by Lockner, Summers, Moore and Byerlee (1982), Jafari, Amini Hosseini, Pellet, Boulon and Buzzi (2003), Tembe, Lockner and Wong (2010), Lee, Lee and Jeon (2012), Indraratna, Premadasa, Brown, Gens and Heitor (2014)."

Jan 1, 2015