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By Christopher Boys

"Many water inflows in Saskatchewan potash mines are linked to salt anomalies. Potash ore and three anomalies in the PCS Cory potash mine in the Patience Lake Member of the Prairie Evaporite Formation were studied to understand the processes involved in their formation. Another goal was to find geological indicators of the proximity of anomalies. A geological model that relates the potash to the salt anomalies has been developed.Up to five post-burial facies may be recognized. These range from carbonate-mud collapse breccias to bedded sylvinite, and probably result from post-burial leaching. In this model, the same fluids that caused widespread recrystallization and possibly enrichment of the potash salts, started by dissolving huge cavities in the evaporites. The effects of the leaching were highly variable, indicated by selectively preserved delicate laminae and chevron textures, to deformed and totally dissolved salt beds. In at least two major events, Late Devonian and Cretaceous, collapse structures may have acted as conduits for overlying formation waters to cause pervasive leaching and recrystallization of the Prairie Evaporite Formation.Geological indicators of the proximity of an anomaly may include: a change in insoluble seam color from greenish-gray to mottled brown and greenish-gray, unusual local increases in ore grade, large patches (e.g., >200 cm2) of sylvite-poor potash crosscutting units near the top of the ore wne, and drops in topography > 10 m of the marker seams. Anhydrite was more common in an anomaly than in ore. The local abundance of anhydrite in ore may indicate the proximity of some salt anomalies. Once an anomaly has been encountered, indicators of a major collapse feature may include: stretched clay seams, folded beds, small collapse features (1 m to 20 m), numerous washouts, or split clay seams with injected salt. Any number, or none, of these indicators may be found close to a major collapse feature."

Jan 1, 1993

By J. Donovan

Underhand cut and fill mining is being planned for selected areas at the David Bell Mine where high ground stresses have resulted in particularly challenging mining conditions. In order to test the placement and performance of a variety of underhand cut and fill paste mats three different designs have been installed and extensively instrumented along the A-Zone 9C ore sill. The sill is approximately 87m long, 4.0m high, and 5.0m average width. The sill was broken into 3 sections each of which will contain one of the sill mat designs. The underhand sill will be mined 3.75mW x 4.0mH, allowing for some overbreak while minimizing the risk of the back span exceeding the design limit of 4.0mW. Each test sill mat includes pre and post-support and includes 0.5m (18?) broken muck mat placed along the sill floor. Upon developing beneath these mats quantitative and qualitative measures will be used to determine which design is the most suitable for application in underhand mining at David Bell.

May 1, 2007

By Julian Boldy

"A review of lI5 significant volcanogenic massive sulphide discoveries in the Canadian Precambrian during the past 65 years reveals that only 7% resulted from surface exploration methods aimed at depths below the effective reach of current geotechnical systems. This has been due to the relative ease of shallow discovery, resulting in the harvesting of ore deposits within 100 m of surface. This surficial layer has been more or less effectively supersaturated by routine exploration. In view of the fact that a mining district's metal content is not likely to be confined to a surficial layer, the time has come to explore the vertical dimension, prospecting for ore at depths in excess of 150 m in productive districts.Essential to this task is an understanding of the Precambrian volcanogenic ore deposit model. The deposits generally have .a tendency to be associated with the terminal phases of felsic volcanism, and to be located along certain time-stratigraphic horizons, marked by the products of volcanic exhalation. The significant massive sulphide deposits are discrete entities, ranging from the top 5% of deposits greater than 45 million tonnes in size, with a surface area of 0.30 km2, to median-sized deposits greater than 1.2 million tonnes in size with a surface area of 0.02 km2. These significant economic ore deposits range in value from $5.5 billion for the top 5% of deposits to $125 million for median-sized deposits. In terms of their frequency of occurrence, the former group has a 4% distribution and the median-sized deposits have a 15% distribution.An historical review of many of the principal Precambrian mining districts, such as Noranda and Flin Flon, shows that major tonnages are usually discovered during the initial phase of application of each new geotechnical search system, until carried to its ultimate limit of effective depth penetration. With the exception of the Noranda district, the mean depth of ore discovery in the other districts is still generally confined to within 50 m of surface.Targeting deep ore is difficult. One effective prospecting method is the detection of fracture-controlled mercury leakage haloes in outcrop (or core) above and peripheral to blind deposits. This technique has proved to be a useful pathfinder, and focuses attention on deposits buried at depths in excess of 700 m in some instances. Down-hole EM systems also promise to be effective in locating deposits previously bypassed by drilling. In addition, trend surface analysis programs of trace element geochemistry should be used as an aid to targeting ore by directing exploratory drilling along the plane of ore-hosting stratigraphy.By definition, mining districts have a proven ""favourability"" for the occurrence of ore. Discovery probabilities in these districts will be considerably enhanced if future search efforts are concentrated below a depth of 150 m, and more use is made of ""deep"" ore search systems coupled with sound geological reasoning. Deep drilling programs to a depth of800 m should initially be designed to search for the top 25% of deposits greater than 3.3 million tonnes in size, with a surface area of0.05 kmt. :a value of$310 million and a 12% frequency of occurrence; This can be accomplished for an over-all cost approximating $40,000 per drill hole. If the search depth is limited to 400 m, the over-all cost of each drill hole is $20,000, equivalent to expenditures routinely allocated to grassroots exploration drilling in the remote greenstone belts of the Precambrian. Depending on a company's objective, prospecting for deep ore offers a stimulating challange - though risky, it has its rewards."

Jan 1, 1981

By Zhang Junzhi

This paper relates cross-border mergers and acquisitions (M&A) risk management theory to actual coal enterprises in China. The 3 phases of M&A are preparation, implementation and integration. By using the Analytic Hierarchy Process and fuzzy evaluation methods, we will try to establish a model to assess risks of the cross-border M&A of China?s coal enterprises. We then apply this model to the case of Yankuang Group acquisition of the Felix Company and receive the assessment results. There are significant reasons for quantitative research on risks of cross-border M&A of China?s coal enterprises, such as effective prevention and risk-aversion, and facilitation of cross-border M&As.

Aug 1, 2013

By M. A. Power

The diamondiferous Drybones Bay kimberlite pipe is the largest pipe (900 m by 400 m) discovered to date in the Northwest Territories. The pipe intrudes granodiorite of the Archean age Defeat Pluton and contains crater, reworked crater (epiclastic) and diatreme facies kimberlite. In-situ measurements of seismic p-wave velocity were recorded with in-line refraction arrays over representative areas. Refractions from fresh kimberlite were recorded over epiclastic facies kimberlite in the eastern portion of the pipe and returned an average velocity of 4300 m/s. Refractions from weathered kimberlite were recorded on all lines and returned velocities ranging from 1900 m/s to 2200 m/s. Granite surrounding the pipe returned an average velocity of 5400 m/s. The results indicate that there is a definite contrast in seismic velocities between kimberlite and country rocks at Drybones Bay and suggest that seismic refraction surveys may be an effective means of screening kimberlite targets in glaciated areas underlain by igneous or metamorphic rocks.

Jan 1, 1998

By A. J. Sinclair, N. Champigny

"The Cinola gold deposit in the northern Queen Charlotte Islands, British Columbia, is in a clastic sequence consisting of a lower shale of the Late Cretaceous Haida Formation and an overlying interbedded sequence of pebble conglomerate and coarse-grained sandstone of the Middle Miocene Skonun Formation. Both formations are intruded by a stock and dykes of porphyritic rhyolite. Two K-Ar model ages indicate mineralization and probably porphyritic-rhyolite intrusion at about 14 Ma (middle Miocene). A splay of the Sandspit fault system constitutes the footwall on the west of the deposit.The Cinola deposit can be classed as Carlin-type based on features such as (1) small particle size for gold, (2) Tertiary age of mineralization, (3) element abundances (e.g. high Hg), (4) dominantly argillic alteration, (5) a structural setting associated with major faults, (6) porosity of the host rock and (7) spatial and possibly genetic association with felsic intrusions. Gold is widespread and occurs mainly as grains of< 0.5 11-m in silicified sedimentary rock, and in quartz veins. Locally, coarse > 100 11-m particles of native gold occur in quartz veins, especially in strongly brecciated porphyritic-rhyolite. Ore minerals are mainly pyrite and marcasite, but include small amounts of chalcopyrite, sphalerite, galena, pyrrhotite, cinnabar, tiemannite (HgSe), rutile, magnetite, hematite and limonite in addition to native gold and electrum. No silver minerals have been found; silver was found in gold particles in amounts varying from 6.2 to 24.2 weight per cent. Alteration products are sericite, illite, kaolinite and chlorite, with abundant quartz of several stages.The host rocks, specifically the Skonun Formation, formed as an alluvial plain facies in a braided river system discharging into a marine basin in early Middle Miocene time. During the Middle Miocene, this sequence was intruded by a rhyolitic stock. The highly porous and permeable Miocene clastic sequence apparently provided an optimum setting for the development of a large geothermal system, the energy for which probably derived from the rhyolite stock. Mineral deposition followed a well-defined paragenesis, which, from oldest to youngest, is: (1) precipitation of iron sulphide minerals, and early quartz; (2) several stqges of quartz veins, with deposition of sphalerite succeeded by galena, chalcopyrite and visible gold. Micron-size gold was precipitated throughout these two stages of mineral deposition. Argillitization of the host rocks probably in part coincided with the mineralization and continued during cooling of the geothermal cell.In-situ reserves have been estimated at 41.1 million metric tons averaging 1.85 g Au/tonne using a cutoff grade of0.86 g Au/ tonne."

Jan 1, 1982

By Rachel S. Prudhomme, Michael L. Jeremic

"The consolidation of mine backfill by free zing is a concept which has been under study in the mining engineering laboratories at Laurentian University during the past three years. The proposed underground application of freezing involves the artificial freezing of in-situ backfill by means of a refrigerated brine solution which would be circulated through a circuit off freeze pipes. The most interesting findings to date are: (I) The uniaxial compressive strength off frozen fill is considerably higher than that of cemented fill in a ratio of 20:1 (aggregate to cement), and (2) load deformation characteristics of the frozen fill suggest that a higher ice content results in more brittle failure and that samples which have initially failed can still support up 10 one-half the ultimate load without additional failure.Although at this early stage a derailed economic analysis of the procedure has not been possible, a general evaluation of the costs involved suggests that the method could be competitive with the hydraulic placement of cemented backfill. Results obtained from laboratory investigations indicate that the freezing of backfill is a structurally feasible option .IntroductionGround consolidation by freezing is based on the principle of transformation o f water contained in an aggregate-slurry into ice, which act s as a binding agent between the bulk particles, and which results in the transformation of a granular soil into a ""rock -type"" material. The abrasive nature of the particles enhance s the strength o f the ice by providing internal friction. As a result of this internal friction, the chances of plastic flow of the frozen mass when in a loaded condition are reduced(1). T he strength of a frozen aggregate is al so dependent on the grain shape of the aggregate particles which may or may not promote particle interlocking(2) and on the temperature since, below the freezing point of the water/aggregate mixture, the strength of the frozen mass increase s with decreasing temperatures.In the shaft sinking industry, artificial freezing of loose , unconsolidated soils has been in practice for several decades. Shafts for Saskatchewan &apos;s potash industry have been sun k to depths of 3000 feet by employing artificial freezing to stabilize the Blairmore Formation(3). The common procedure for freezing ground for shaft sinking is summarized as follows(4,5): I) 150 mm diameter bore holes spaced on 1.5 m centres are drilled in a circular pattern with a radius of 1.5 m outside the periphery of the proposed shaft."

Jan 1, 1985

By John Hoffert, Darren Colwell, Greg Tucker, Jeremy Kinch, Greg Rasmussen

"The Kemess Mine, a major producer of gold and copper, is located in north-central British Columbia. Kemess was brought into production in May 1998 by Royal Oak Mines. On February 11, 2000 Northgate Exploration Limited acquired Kemess Mine from receivership. Since acquisition in 2000 Kemess has seen many accomplishments, including the reduction of costs by 40%.One of the largest site capital costs was the construction of the tailings storage facility dam, which when finished will be one of the largest earth filled dam structures of its type. The existing construction design by AMEC called for a kilometer wide rock dam to be built from the 1350 M elevation to the 1504 M elevation at a 5.5:1 slope by hauling over 30 million tonnes of non-acid generating waste rock 7-kilometers from the open pit to the tailings dam, which was highly expensive.Kemess realized an opportunity for cost reduction was possible if the dam could be built from suitable quality tailings sand; however the sand did not meet the neutralizing potential ratio specifications. It was determined that cycloning combined with flotation to reduce pyrite concentration in the sand would produce a non-acid generating product for dam construction. The sand plant design challenges were to remove the sulphides from the tailings to obtain an NPR greater than 2:1 and provide a consistent sand product for the construction with a fines content of less than 15% passing 200 mesh. After a 2-year testing design and construction period, the sand plant was successfully started at the end 2002 resulting in higher than expected sand quality and production rates.This paper describes the plant design phase, commissioning, and operation of the tailings sand plant for construction of the tailing storage facility dam to enable us to meet all the engineering and regulatory requirements. The many challenges faced were successfully met using several innovative designs. The operational, economic, and environmental benefits are detailed."

Jan 1, 2004

"Polycom, a new approach to ore processing based on pressure comminution, is obviously a very attractive alternative to conventional processing methods.Since a full-scale pilot plant was commissioned in 1986, more than 125 commercial installations, with capacities up to 1000 t/hr, have gone ahead.Already successfully used in processing cement clinker, limestone, coal, and other minerals, Polycom high pressure grinding results in:o Significantly reduced capital costs, because smaller units can be used m new installations;o Capacity increases of up to 100% in existing facilities; and o Operating economies that include energy savings of 20% or more, and reduced wear parts consumption.1. IntroductionAutogenous or semi-autogenous mills in conjunction with rod or ball mills are used with preference for ore processing. Most ball mills are of closed-circuit design and operate with mechanical classifiers (spiral or rake classifiers) or hydrocyclones. In other words, the ores undergo wet primary grinding, since slurries are required for the downstream separation stages anyway. This paper presents a new grinding system based on high pressure comminution of ores. This grinding process allows:- Energy savings of up to 20 % or more- Capacity increases of up to 100 % and more- Reduction of wear costs- Smaller units for new installation and thus- Reduced investment costsThese advantages are highly interesting for both new installations and conversion projects, particulary in cases where an increasing hardeness of the ore, i.e. rising Bond Work Index, reduces the output of the plants or where the metal assay of the ore decreases and the capacity of the existing systems has to be increased. POLYCOM high-pressure grinding rolls have established themselves with great success already for grinding cement clinker, granulated blast furnace slag, limestone, cement raw materials, coal and other materials.Meanwhile more than 250 high pressure grinding rolls have been installed worldwide. Capacities up to 1.000 t/h with roller diameter up to 2.8 m and drive units up to 2.400 kW are installed."

Jan 1, 1991

By Paul Bedard, Réal Daigneault, Guy Perrault

"La mine Lamaque est située a Val d&apos;Or, Québec; les roches hônes appartiennent au groupe de Malartic, partie supérieure, et sont des andésites et des pyroclastites. On y retrouve deux formes d&apos;intrusifs; des petites cheminées (ca. 150 m D) et des dykes (ca. 10 m d&apos;epaisseur). Les petit es cheminées contiennent:1 - des diorites et des tonalites (cheminées principale, est et ouest) d&apos;affinité calco-alcaline: Zr 140 ppm, Sr 761 ppm, P2O5 0.31% et (La/Sm)n 3.0;2 - des diorites (cheminée 4) d&apos;affinités tholéiitique: Zr 32 ppm, Sr 181 ppm, P2O5 0.27% et (La/SM)n 1.5.La diorite de la cheminée no 5 contient deux fractions, une de chacune de ces deux affinités. Les dykes tant de porphyre feldspathique quartzifére que ceux de prophyre feldspathique sont d&apos;affinité calco-alcaline: Zr 83 ppm, Sr 500 ppm et P2O5j 0.10%.Le gisement de 10 mine 2 est filonien: veines subhorizontales (""flats "") surtout et veines sub-verticales dans des zones de cisaillement. Le dernier réajustement structural de direction de compression nord-sud a broyé le quartz des veines existant es et rendu possible leur minéralisation. Les veines minéralisées contiennent du quartz, de la tourmaline, de la calcite avec des traces de scheelite, de pyrite et d&apos;or; elles sont bordées par de minces (2 à 20 cm) bordures d&apos;altération où l&apos;on retrouve un enrichissement en carbonate, paragonite, apatite, rutile, saphène et zircon et où les phases ferromagnésiennes sont disparues. On a documenté le migrations géochimiques suivantes:I - de la bordure d&apos;altération vers l&apos;éponte, K2O, Rb et MgO;2 - de l&apos;éponte vers la bordure d&apos;altération, Na2O;3 - de l&apos;éponte vers la veine, SiO2.P2O5, TiO2, Zr, Y, Nb et CaO sont enrichis dans la bordure d&apos;altération."

Jan 1, 1983

By G. F. Cross

INTRODUCTION THE electrical system associated with the mining development of the Hudson Bay Mining and Smelting Company, Limited, at Flin Flon, Manitoba, may be conveniently divided into three main parts, namely, the Island Falls power plant, the transmission line, and the distribution systems at the mine and metallurgical plants. For a description of the Island Falls power plant and the transmission line, the reader is referred to the paper, to be presented at this meeting, by R. W. Davis and M.F. Huffaker (1). The transmission line and sectionalizing combinations are shown diagrammatically in Figure 1. The present paper deals with the distribution systems at the Flin Flon mine and metallurgical plants. THE FLIN FLON DISTRIBUTION SYSTEM In the high-tension sub-station at Flin Flon, each incoming 110 kv. line is provided with manually operated, gang-type disconnecting switches. Each line is connected to Canadian General Electric type F.H.K. 39-60B-F.2 T.P.S.T. 110 kv. 400 amp. oil circuit breakers, each provided with M.K.4 centrifugal motor-operated closing mechanism. Gang-type disconnecting switches are installed on each side of incoming line breakers, and a complete ring bus system is formed through station tie breaker, which is&apos; further provided with gang-type disconnecting switches on either side. The?bus tie breaker is of Canadian Westinghouse design, type G.22B, 110 kv., 400-amp., solenoid-operated. All three breakers are provided with bushing-type current transformers, and the two line breakers are further equipped with bushing-type potential devices. Oxide film lightning arresters (121 kv.) are installed on each incoming line and are located outside the station. Each line is further provided with interlocked gang-operated ground disconnecting switches. All disconnecting switches are mechanically connected to auxiliary switches, which provide pilot service to indicating lamps in the remote-control room, located in a separate building.

Jan 1, 1935

By Ben Murphy, Tomi Maksimainen, Antti Rinne, Ishmael Muzinda, Toni Mattsson

"A 500m3 flotation cell was commissioned during 2014 at the Kevitsa Mine in northern Finland working as the first rougher in the copper flotation circuit. Treating around 850tph with an average grade of 0.3% Cu, the TankCell® e500 has run with an average copper recovery of 71% and an average enrichment ratio of 50 during early optimization test work. In addition the cell has proved to be very energy efficient, being operating with a specific energy of around 0.4kW/m3 under production conditions.A review of the installation and operation of the TankCell® e500 at Kevitsa will be presented. Metallurgical performance of the cell during the operating period will be discussed on the basis of on-line analysis and the metallurgical samples collected during early optimization campaigns.IntroductionThe past three decades have seen a rapid increase in the size of mechanical flotation cells. This has been largely driven by demand from the copper industry to process larger volumes of material due to combination of declining head grades and the desire to benefit from the economies of scale (Lynch, Harbort and Nelson 2010). During this period Outotec has been at the forefront of development of large flotation technology with an enviable scale-up track record; 100m3 (1995), 160m3 (1997), 200m3 (2002), 300m3 (2007), 500m3 (2012) to the largest commercially available cell at 630m3 in 2013. This scale-up methodology has been developed, tested and validated (Elgueta et al., 2009; Coleman & Dixon, 2010) by the large installation base of cells in the 300m3 size class operating (over 400). The learning from large cell operation are then reviewed and incorporated back into new designs and scale-up practices (Murphy, Miettinen, and Yanez, 2014)."

Jan 1, 2016

By Andre Panteleyev, Charels S. Ney, John M. Anderson

"Sam Goosly prospect, 22 miles southeast of Houston, B.C., was discovered in 1967 through geochemical reconnaissance. Soil sampling interpreted with respect to an east-to-west ice movement led to drilling targets.Mineralization is in a window of rocks thought to be Hazelton Group surrounded by Tertiary volcanic rocks and intruded by two stocks separated by about one mile. A westerly quartz monzonite stock is dated 61.1 m.y. and an easterly gabbro-monzonite complex is dated 52.5 m.y. The Tertiary volcanics are trachyandesites shown by the B.C. Department of Mines and Petroleum Resources to be in part extrusive equivalents of the gabbro, and they overlie Hazelton rocks uncomformably. Copper-molybdenum mineralization is sparsely developed in the westerly stock. Silver-copper mineralization forms an elongate west-dipping slab between the stocks in Hazelton rocks, which are continuously pyritized. The gabbro stock is not mineralized, but some dikes related to it are slightly so. Tertiary rocks are pyritized, but are not known to carry copper-silver mineralization. Hazelton rocks are divided into a lower conglomerate, an intermediate pyroclastic unit and an upper mainly sedimentary unit. They form a west-facing homocline. Coppersilver mineralization resides in the pyroclastic unit, mainly in a massive dust tuff through which are lenticular units of lapilli tuff. Well-mineralized rock is typically a breccia of light fragments in a dark chlorite-sulphide matrix. Sulphides are pyrite, chakopyrite and locally pyrrhotite, with very minor tetrahedrite, s phalerite and other sulphosalts. Rock alteration is predominantly a pervasive pyrite-sericite type, with widespread tourmaline, scorzalite, gypsum, ankerite and traces of fluorite. The most evident control of the copper-silver mineralization is the gross parallelism, over a strike length of 1.5 miles, to Hazelton strata, particularly a massive dust .tuff unit. In detail, mineralization crosscuts bedding and there is no appreciable banding within sulphides . A strictly syngenetic origin is untenable, but some initial concentration in a volcanogenic environment with subsequent modification by thermal processes seems likely."

Jan 1, 1972

By Jan Drzymala, Przemyslaw B. Kowalczuk

Froth flotation is widely used for upgrading of ores and other materials. Efficiency of flotation depends on many parameters, including type, chemical structure and dose of flotation reagents. Selection of a proper frother in flotation depends on the material used, necessary dose of frother and its selectivity. The selectivity of flotation can be characterized by proper separation factors and indices. In this paper separation selectivity and power of frothers were evaluated basing on separation data for a given material and frother, plotted as the recovery of the useful component in the concentrate versus the recovery of the remaining components in the tailing. Such a plot is called the Fuerstenau upgrading curve. The selectivity was defined as the location of the whole upgrading curve in relation to no and ideal separation lines, expressed on the scale from 50 (no separation) to 100% (ideal separation). In turn, the flotation power was defined as the dose of frother to reach a certain upgrading level at which recoveries of the useful and unwanted components are equal. The power and selectivity of frothers were determined for the Kupferschiefer stratiform copper ore floated in the presence of a fixed amount of xanthate and varying doses of frothers using a laboratory flotation machine. Basing on the separation results for different poly(propylene glycol) (CnH2n+1O(C3H6O)mH, CnPm) and poly(ethylene glycol) (CnH2n+1O(C2H4O)mH, CnEm) alkyl ethers, it was found that the concentrate yield and recovery of copper as the useful component in the concentrate were greatly influenced by the type and dose of frother. However, the same results plotted in the form of the Fuerstenau upgrading curve clearly indicated that the selectivity of frothers was similar, while their power was different. It proves that both selectivity and power of frothers are useful parameters for characterizing flotation systems.

Jan 1, 2016

By S. N. Kalyakin, D. S. Flett, M. A. Mulagaleeva, N. V. Gudkova, S. S. Serdyuk, V. I. Kuzmin, Institute of Chemistry and Chemical Technology SB RAS, O. A. Logutenko, V. N. Kuzmina, V. G. Lomayev

"The Chuktukon niobium-rare earth elements ore deposit is located in Siberia (Russia). Weathered carbonatite crusts are the basis of the ore deposit. The deposit itself is 3.5 km in length, about 800 to 1400 m in width and up to 200–300 m in thickness. The ores are composed of iron-manganese oxides (hydrogoethite, hematite, psilomelane, pyrolusite) and contain 3–7% of rare-earth phosphates (florencite, monazite) and 0.5–1% of niobium oxide (pyrochlore). The ore is completely finely dispersed and consists of oxide particles formed of compact, dense aggregates which makes ore dressing as well as leaching of the rare and radioactive elements very difficult. Several options for processing of these ores have been considered: 1) reduction of the iron oxides to magnetite followed by beneficiation with magnetic separation to produce a rare metal concentrate; 2) processing of the rare earth elements (REE) containing minerals by direct alkaline-acid treatment; 3) processing of the ores using nitric acid leaching in an autoclave.INTRODUCTIONThe Chuktukon niobium-rare earth metal ore deposit is located in Siberia, in the Krasnoyarsk region, 110 km from the Boguchan hydroelectric power station which has recently been commissioned. This mineral raw materials is capable of providing impetus for the modernization of the Russian rare metal industry because of its qualitative and quantitative characteristics. The deposit is located in a region of promising industrial development and is a part of the territoriy where the Russian Federation’s Program “Complex Development of the Lower Angara Region” is currenly being realized. The main program directions are creation and development of industrial activities in sectors such as power, metallurgy, oil and gas, gold, rare-metals, and timber. The program will aid the development of the niobium and rare-metal resources of the Lower Angara and neighbouring regions as well as increase the national production of REE and therefore import substitution (Lapin, 1997; Lomaev & Kuzmin, 2003; Lomaev & Serdyuk, 2011; Serdyuk, Lomaev, & Kontorovich, 2000)."

Jan 1, 2016

By Lei Pan, Roe-Hoan Yoon

"Sea water flotation is becoming a reality due to shortages of fresh water. To better understand the mechanisms involved in sea water flotation, we have studied the effects of KCl and MgCl2 on the surface forces present in the wetting films of water formed on hydrophobic surfaces. The measurements have been conducted using the force apparatus for deformable surface (FADS), which is capable of measuring both the surface and hydrodynamic forces responsible for bubble-particle interactions. The results obtained with the gold surfaces hydrophobized with butanethiol (C4SH) show that the wetting films of Ultrapure water do not rupture despite the relatively high water contact angle (??= 80o) and the presence of a long-range hydrophobic force with a decay length (D) of 25 nm in the film. The film is metastable with its equilibrium thickness (he) at 140 nm, where the repulsive double-layer force is equal in magnitude to the capillary force as shown in Figure 1. The film loses its metastability and ruptures in a 10-2 M KCl solution, in which the double-layer force decreases substantially due to the decrease in Debye length (?-1) while the decay length of the hydrophobic force remains as large as 23 nm.The effects of MgCl2 has also been studied using a C4SH-coated gold surface with a water contact angle of 87o. It has been found that in a 10-4 M solution double-layer force decreases due to the decrease in the negative ?-potentials and Debye length, which should help destabilize the wetting film. However, the film remains stable due to the decrease in the decay length of the long-range hydrophobic force from 45 nm in Ultrapure water to 14 nm in the MgCl2 solution. Thus, the results obtained in the present investigation support the view that the difficulties in sea water flotation may be due to the presence of MgCl2 rather than the presence of NaCl in sea water (Ramos, et al., 2013)."

Jan 1, 2016

By A. Roy MacLean

"In the Maritimes, there are twelve coal areas. From east to west, these include the Sydney coal field, the St. Rose - Chimney Corner, Inverness, Mabou, Port Hood, Pictou, Colchester - Debert, Springhill, Joggins - Chignecto, Beersville, Lake Stream, and Minto. The first eight are in Nova Scotia while the remaining four are in New Brunswick.In all these areas, the coal was formed during the Carboniferous period, which existed some 300 million years ago. However, within this period not all coal formation took place during the same time. There were three main intervals, which occurred at the time that the Riversdale, Cumberland and Pictou groups were laid down (Hacquebard, 1970). The oldest coals are those of the Riversdale Group. These coals were of rather limited extent, and only a few mineable seams are present, particularly at St. Rose -Chimney Corner and Port Hood. From these two areas only 2 M tons have been extracted, and 'measured' resources of 7 and 9 M tons respectively remain. The Cumberland Group coals are confined to Cumberland County and include the coals of Springhill and Joggins River Herbert -Chignecto. Some 43 M tons have been removed and only 7 M tons of 'measured' coal remain, with an addit10nal 39 M tons of 'inferred' resources. However, there are additional resources at Springhill, which will be discussed in more detail in a later section. The coals of the Pictou Group are the youngest and the most abundant, both in actual number of seams and in regional distnbution. These coals were formed during the Westphalian C and D, a time during which the main coal deposition in Europe also took place. Here belong the coals of the Sydney, Inverness, Mabou, Pictou, Debert, Beersville, Lake Stream and Minto fields. Their total production amounted to 469 M tons or 91 % of the Maritime total of 514 M tons. The remaining resources of all Pictou Group coals have been calculated at 254 M tons of 'measured' coal and 949 M tons of 'inferred' coal. As can readily be seen, the bulk of both past production and remaining resources occur in the Sydney coal field. The Sydney figures represent 73% of total production, and 87% of total 'demonstrated' resources in the Maritime Provinces. Next to Sydney, the Pictou coal field has been the greatest producer, with 59 M tons; it also has the second largest 'measured' resources, amounting to 25 M tons. However in terms of 'inferred' coal resources, the Mabou coal field, ~ith 140 M tons, ranks second to Sydney."

Jan 1, 1985

By The Mine Staff

THE PROPERTY of the Lamaque Mining Company, Limited, ?is located in the Town of Bourlamaque, seventy miles east of Noranda, in Bourlamaque township, Abitrbi county, north western Quebec. Gold production commenced at Lamaque in April, 1935, with an initial mill capacity of 250 tons per day. The capacity was doubled in November of the same year, and in December, 1937, it further increased to 1,200 tons per day. During the war years the mill operated at a reduced tonnage, but in 1951 milling units were added along with complementary crushing and shop facilities to bring the capacity to 1,500 tons per day. Finally, in 1953, the capacity was raised to 2,000 tons per day, which rate is being maintained at the present time. The total production at Lamaque from April 2nd, 1935, to December 31st, 1956, has been 9,168,901 tons of ore from which 2,208,168 ounces of gold was recovered. The total value of this production , excluding E.G. M.À.*, was $77,869,653.

Jan 1, 1957

By G. R. MANSON

The Brisco Barite Mine lies 70 km south-southeast of Golden, British Columbia. Barile mineralization occurs in a northstriking brecciation zone within Ordovician-Silurian Beaver/ oot dolomites and quartzites. Brecciation was caused by faulting related to the Mount Forster-Steamboat Fault. The main barite vein occupies a fault zone and is up to 12 m wide and over 250 m long. It is light grey to white, fine grained and compact; BaSO4 content is 9/. 70 per cent. Production started in 1945 and has continued to the present. Barile originally was removed from an open pit; later, an adit, begun in 1957, reached more than 240 m along the vein, 15 m below the pit floor. Today ore is hoisted from a decline resting some 37 m below the pit floor.

Jan 1, 1984

By M. Jarvis, D. B. Dreisinger, T. Hitchins

Mineral carbonation (MC) has been extensively researched all over the world since it was found as a natural exothermic process to permanently and safely sequester CO2. In order to accelerate the natural process, various methods for carbonation of Mg-/Ca-silicate minerals and other industrial wastes have been studied. It has been found that the MC efficiency will increase with an increase of CO2 pressure, retention time, temperature, mass ratio of Mg or Ca to Si in minerals, specific surface area, and the slurry concentration in a specific range, and with the introduction of an effective catalysts, for example, 1M NaCl and 0.64M NaHCO3 or carbonic anhydrase. However, there still is not a successful industrial application because of high economic cost and slow reaction rate. It is not economic to exploit Mg- and Ca-silicate minerals deposits or tailings to sequester CO2 by MC, due to the cost of grinding and heat pre-treatment and in some cases the whole sequestration process may result in more CO2 emissions than the amount of CO2 sequestered, due to the requirements of energy inputs. The process however, may be profitable as a whole (with carbon credits). It is suggested to combine MC with recovery of valuable metals from ore deposits in order to reduce the cost for MC by cost sharing for mineral recovery.

Jan 1, 2017