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By Laszlo Imreh, Pierre Trudel, André C. Tessier

"The Siscoe gold mine is ranked as the fourth largest mine in the history of the Val d' Or mining district with a total production of 27.4 tAufrom1929 to 1949. Most of the gold mineralization occurred in quartz veins, hosted in a small (.69 km2) intrusion of altered quartz gabbro known as the Siscoe stock. The southern contact of the Siscoe stock is crosscut by a major shear zone (the ""K"" zone) trending 295/80 NE and from which gold mineralization was also exploited within the limits of the stock. Field and petrographic observations of the Siscoe stock combined with chemical analyses of major, trace and rare earth elements of the stock and its volcanic host rocks (Dubuisson Formation) suggest that:The Siscoe stock comprises four alteration facies formed from a homogeneous precursor: 1) the actinolite - Mg-chlorite facies, characterized by low FeOt,Na2O andTiO2 , and highAlp3 and MgO; 2) the albite- Fe-chlorite facies, containing high concentrations of FeOt and Nap; 3) the Mg + Fe-chloritefacies, which is transitional between the actinolite- Mg-chlorite and albite- Fe-chloritefacies; 4) the carbonate-chlorite facies, which consists of rocks that were subjected to extreme hydrothermal alteration, is spatially associated with mineralized veins and part of the K-zone. The first three facies are depleted in SiO 2, CaO and Au, and enriched in MgO, relative to fresh rocks of the Siscoe stock and the equivalent rocks of the Dubuisson Formation.Hydrothermal fluids introduced mainly along the K-zone ""channelway"" induced three types of element remobilization, resulting in the various alteration facies: 1) redistribution of elements within the stock from one facies to another (e .g., FeOt, Nap, Ti02 migrated from the actinolite- Mg-chlorite facies to the albite- F e-chlorite and Mg + Fe-chlorite facies); 2) remobilization of elements from the intrusive rocks into veins (e.g ., SiO 2 and CaO ); 3) introduction of elements by hydrothermal fluids in rocks of the Siscoe stock (e .g., Al2O3, MgO, H2O, CO2 and FeOt).The Siscoe stock and the Dubuisson Formation form part of the same tholeiitic suite. Similarly, the Bourlamaque batholith and the Val d'Or Formation belong to a single calc-alkaline suite. In view of this relationship, dissimilarities between the petrochemistry of the Siscoe stock and the Bourlamaque batholith suggest that the two intrusions are not co-magmatic.Finally, gold may have been leached from rocks of the Siscoe stock and remobilized into the quartz-carbonate mineralized veins. In order to account for the total production at the Siscoe mine, approximately 1.2 km3 of the Siscoe stock is thought to have been partially leached of its gold."

Jan 1, 1990

By H. Itou

A mechanism of scorodite formation at ambient pressure was investigated using transmission electron microscopy (TEM). Several types of iron arsenate were obtained from Fe/As solutions (Fe/As = 1.0 and 1.5) at pH values of 1.0, 1.25 and 1.5 at 95°C. Amorphous FeAsO4.xH2O was precipitated from solutions having a higher mole ratio of Fe/As at pH l.5, even after 9 hours. A few micron sized particles were observed by SEM, but these proved to be agglomerates of 10-50 nm amorphous FeAsarxH2O particles when observed by TEM. This means that supersaturation of the solution causes the acceleration of nucleation of iron arsenate hydrate. Crystalline scorodite was obtained from a solution in which the Fe/As mole ratio was unity, at pH l.0 and pH 1.5, after 3 hours. Almond-type crystalline scorodite particles were observed by TEM and most of them showed high crystallinity. The addition of scorodite seed material enhanced the crystallization. Amorphous FeAsO4.xH2O, however, was observed at the surface of the seeds during the early stages of precipitation. It is postulated that crystalline scorodite is not directly precipitated even on crystalline scorodite seeds, but requires a certain time to crystallize on the seed material.

Jan 1, 2006

By G. H. Hope, A. R. Maycock

"La Mine Doyon is a gold mining operation located in northwestern Quebec, approximately 35 km east of Rouyn-Noranda and 85 km west of Val d'Or. The mine is jointly owned by Lac Minerals Ltd. and Cambior Inc. with Lac Minerals as the manager. Production statistics as of February 1987 are 6.4 million tonnes milled at an average grade of5.8 g/t Au. Current reserves of9.9 million tonnes at 5. 7 g/ t Au to a depth of400m have been outlined. Indicated reserves below this horizon could considerably increase this reserve.The mine currently consists of two open pit and two underground mine operations, producing approximately 3600 tonnes per day of ore at an average grade of6 g/t. The ore is currently processed at the La Mine Doyon mill at a rate of1400tid and at Lac's East Malartic mill at 1950 t/d. Ore is also processed intermittently at Lac's Les Terrains Auriferes mill and at Noranda's Horne Division.La Mine Doyon is currently in the midst of a program to expand and upgrade the mill at La Mine Doyon. The expansion to 3000 t/day includes the conversion of the existing crushing and grinding circuits to a SAG (semi-autogenous grinding) mill circuit and the existing filter wash plant to a CIP (carbon-in-pulp) recovery plant. The economics of this project are based on reduced operating costs (milling and trucking) and improved recovery due to updated technology. HistoryThe area between Noranda and Val d'Or has a long history of mining activity in both base metals and gold, dating back to the early 1930s. More recently, several new orebodies have been discovered and exploited in the area including La Mine Doyon, Lac's Mine de Bousquet, Dumagami, and the Kiena operation.La Mine Doyon was discovered in the early 1970s, and brought into limited production in late 1979. The mine was started on are reserves of 2.75 million tonnes at 6.2 g/t and was, thus, considered a small, short-term operation. Mining started at an initial rate of 550 tI d with all the ore being shipped to Noranda's Horne smelter as flux. When Lac's East Malartic mill became available for custom milling, Doyon commenced shipping to that facility at a rate of 650 t/d. As a result of some equipment additions and an improved understanding of the ore, the East Malartic mill throughput was gradually increased from 650 t/d to the current rate of 1950 t/d."

Jan 1, 1988

By H. Henao, E. Kohnenkamp, L. Rojas

The slags generated in the copper conversion process are mainly composed of Cu2O-Fe2O3-SiO2 with the compounds CaO and Al2O3 in concentrations up to 10 wt%. The present work contributes to the knowledge of the conversion process, generating experimental data for the diagrams of phases Cu2O-Fe2O3- SiO2-Al2O3 and Cu2O-Fe2O3-SiO2-CaO. The experiments were carried out in a tubular furnace at temperatures of 1150°C and 1200°C under a condition of saturation with tridymite. Once the equilibrium was reached, the samples were fast quenched in water. The phases in the samples were observed in a Scanning Electron Microscope (SEM) and the elemental composition of the phases analyzed by means of Energy-dispersive X-ray spectroscopy (EDS) detectors. The addition of Al2O3 and CaO into the Cu2O-Fe2O3- SiO2 system resulted in an appreciable displacement of the liquidus lines, corresponding to an expansion of the liquid in the tridymite primary phase field. INTRODUCTION The conversion process of copper consists of oxidizing Fe and S present in mattes with 60 to 65wt% Cu (up to 16wt% Fe). This process is separated into two stages: 1- Slag blowing: Fe is oxidized, the addition of a flux such as SiO2 (silica) forms a second liquid phase called slag, this phase is removed from the furnace; 2-Copper blowing: in this stage, the matte with low concentration of Fe (<1% w/w) is again oxidized to remove S as SO2 in the exhaust gases. The product of these two processes is the formation of Copper Blister (> 98wt% Cu) (Schlesinger et al., 2011). Unlike the aforementioned conventional processes, in most Chilean smelters, conversion Peirce- Smith Furnaces are loaded with high copper matte (70–75wt% Cu) (Henao & Moyano, 2016). Due to the low concentration of iron in these matte (up to 5wt%), it is considered that separating the conversion process in two stages is neither operational nor environmentally convenient. Therefore, the process is carried out in a single stage (Pradena et al., 2006), generating a slag phase with a high percentage of Cu2O (wt%Cu>40).

Jan 1, 2019

By Ana Adé

The use of gold compounds in homogeneous catalysed organic reactions has been undervalued for many years due to the preconceived opinion that gold is an expensive and extremely chemically inert metal. However, recent reports have changed this assessment and gold salts in small amounts are known to display high catalytic activity.[1] Thus, it has been reported recently that anhydrous AuCl3 catalyses the formation of C-C and C-O bonds (usually mediated by hydrochloric and other protonic and Lewis acids).[2] Some examples include Michael type additions, selective cross cycloisomerisation/dimerisation of propargyl or allenyl ketones, benzannulation between o-alkynylbenzaldehides and alkynes or cyclisation of alkenyl furans. It is noteworthy that some of these reactions[2a] can be also catalysed by silver salts but with much lower yields. The 1,3-dipolar cycloaddition of nitrones to alkenes is a powerful synthetic method that has found numerous applications in the synthesis of a variety of carbon frameworks.[3] Several laboratories have focused on the development of Lewis acidic reagents to modulate the selectivity of the reaction.[4] Despite the extensive study performed, there are not many examples in which a metallic complex catalyses the dipolar cycloaddition. Most of these reactions require the presence of a metallic complex and nitrone in a 1:1 molar ratio. Recently, we have carried out stoichiometric reactions of the N-benzil-C(2-pyridil)nitrone, 1, with different dipolarophiles in the presence of zinc and silver compounds.[5] Apart from an increase of the reaction rate and the selective formation of one of the possible isomers, we have shown the formation of zinc and silver-nitrone complexes during the reaction, which behave as the intermediates in the cycloaddition process. As suggested by the results obtained with silver complexes, we decided to test gold derivatives (in the oxidation states of I and III). Interestingly, we have found that they can be used not only as stoichiometric reagents but they can also mediate these cycloadditions in catalytic amounts (5 to 10 mol % respect to the nitrone). Here we present the results on the 1,3-dipolar cycloaddition reaction of the N-benzil-C(2-pyridil)nitrone (2-PyBN), 1, and methylacrilate, 2, (Eq. 1) catalysed by gold(III) derivatives.

Oct 1, 2003

By G. Agar

"E. Joe We have been working for some years on the elimination ofCANMET thiosulphates from solutions as a means of protecting ground water and fish streams. Alot of these thiosulphates result from the mill use of S02. Is there any possibility that thiosulphates will be generated by this process?Reply I don't know the answer to your question. I can speculate that there is no question that when one adds SO2 and air to a sulphide pulp one generates a host of unsaturated poly¬cyanates. I unfortunately cannot remember the reactions which arise in the cyanide destruction scheme. I think that if thiosulphate was generated the process wouldn't work. It is not oxidizing enough to destroy the cyanide.R. Wagner Would you comment on the actual cost/ton at the Scottie goldPamour mine concentrator? Would $2.50/ton be typical or is thisPorcupine just a ball park figure.Reply We wouldn't disclose Scottie's costs even if we knew them. I depends on the amount of cyanide and thiocyanate in the effluent. I have given you a hypothetical case. With the conditions stipulated the figures I Have given are realistic.K. Konigsmann I do not believe the use of S02 adds significantly to the thio Noranda Mines salt problem Certainly we use SO2 in many of our mills and thio-salt levels in a number of them haven't changed whether we use or don't use S02. For instance, Orchan and Matagami mills treating the same ore side by side in which one was using S02 and the other wasn't, the thio-salt level was virtually the same in both pulp streams. In the case of Brunswick where alot of SO2 is used (20 tons/day) there is a thio-salt problem but it is relatively insignificant.Reply Thank you for that comment. It serves to reassure us that we are not polluting the environment."

Jan 1, 1984

By G. R. Dunning, M. R. Wilson

"Abstract - The early Paleozoic accretionary tectonic regime that was established along the Laurentian margin of the Newfoundland Appalachians provided a favorable setting for shear-hosted gold mineralization along a major terrane suture, the Baie Verte-Brompton Line. The Stog’er Tight prospect is one of several mesothermal-style gold occurrences hosted by shear zones within accreted ophiolites and oceanic arc terranes on the Baie Verte Peninsula. It is an epigenetic, stratabound deposit that is confined to shallow-level gabbro sills within the volcanic cover sequence of the allochthonous Point Rousse ophiolite complex. Gold mineralization at Stog’er Tight is associated with hydrothermal mineral assemblages represented by chlorite-calcite, sericite-ankerite, red albitepyrite (±Au) and chlorite-magnetite alteration zones. Gold occurs with pyrite within the intensely altered gabbro, along the margins of syn- to late-shear, quartz-rich, replacement veins.The Stog’er Tight gabbro served as a rigid body conducive to shear deformation and fluid penetration, whereas, its high Fe-Ti oxide content induced fluid oxidation and gold-pyrite precipitation. Hydrothermal alteration involved progressive CO2, S, Na, and LILE metasomatism, along with significant enrichments in the REE, HFSE, and Th in the high-grade ore zone. Temperatures of vein formation and alteration are constrained by oxygen isotope thermometry to be between 250°C and 480°C. Isotopic compositions of vein quartz from the Stog’er Tight prospect are uniform (??O = +12.5 ± 1‰) and fall within the range cited for many shear-hosted, auriferous quartz veins.A U-Pb zircon igneous age of 483 +3/-2 Ma for the Stog’er Tight gabbro is consistent with its stratigraphic correlation with other Ordovician ophiolitic and volcanic arc/back-arc assemblages in Newfoundland. The U-Pb age of a rare variety of hydrothermal zircon recovered from the high-grade ore zone directly constrains the timing of gold mineralization to 420 ±5 Ma, in accord with a major orogenic episode of Silurian age that produced many of the magmatic and metamorphic rock suites in north-central Newfoundland. Our results are consistent with a post-peak metamorphic, late-magmatic model for gold mineralization that occurred during the waning stages of Silurian orogenesis, driven by emplacement of I-type granitoid intrusions into the crust."

Jan 1, 2000

By T. Guan, G. Fu, X. Zhou, L. Deng

"One kind of tailings from gravity separation of polymetallic mine contains 0.5–0.8% SnO2. The proportion of –0.037 mm size fraction of the tailings is 37.12%, and the distribution rate of SnO2 is 60.32% in it. For this tailings, two processing technology was carried out. One was felt-shaking table gravity separation in which the concentrate with a grade of 30% SnO2 at a recovery of 10% was obtained. Another was flotation-gravity separation in which the concentrate with a grade of 51.20% SnO2 at a recovery of 51.69% was obtained, but the dosage of collectors was as much as 990g/t. Therefore, the experimental research on the influence of grain size composition on the cassiterite recovery were conducted. The results show that: (1) the flotation recovery of the cassiterite distributed in +0.043 mm size fraction is only 10%, flotation recovery is not suitable for it; (2) a portion of cassiterite distributed in –0.01+0.005 mm size fraction could be recovered by flotation, but the tin flotation performance will be worsened rapidly and the dosage of collectors will be increased due to the increase of the content of –0.010 mm size fraction; (3) flotation processing is not suitable for –0.005 mm size fraction of the tailings. According to the results, a new technology has been carried out, that is discarding tailings by gravity separation-hydrocyclone desliming-flotation-gravity separation processing flow. The processing index is close to that of the flotation-gravity separation processing flow, and the collector dosage is decreased to 360 g/t by this processing technology. And, it has been achieved that the cassiterite slime is recovered economically and reasonably.INTRODUCTIONAs the density of cassiterite is higher than that of gangue, gravity separation is considered to be a low cost, pollution free, and effective process for cassiterite recovery (Wills, 2009). However, cassiterite is a kind of fragile mineral, over crushing is easy to take place and a large amount of slime is inevitably produced in the crushing and grinding of cassiterite. For the cassiterite slime exists in –0.043 mm size fraction, the efficiency of gravity separation decreases sharply. The production practice shows that, for the fine cassiterite, the recovery of tin exists in –0.043 mm +0.010 mm size fraction is about 13% through shaking table gravity separation, and the tin exists in –0.010 mm size fraction is almost impossible to be recovered by gravity separation. If flotation is adopted to recover fine cassiterite, the problems of high reagent dosage, high cost, environmental pollution, and poor economic benefit would take place. Therefore, the recovery of cassiterite slime is a worldwide problem. A key way to increase the utilization of tin resource and increase the economic benefit of tin mines is developing suitable beneficiation process for fine cassiterite."

Jan 1, 2016

By D. R. Lentz, C. J. Beaumont-Smith, S. H. Mcclenaghan

"Abstract - The Louvicourt Au-Ag-Cu-Zn-Pb sulfide deposit is hosted by a Middle Ordovician calc-alkaline sequence of aphyric rhyolite flows and associated fragmental rocks at the top of the Flat Landing Brook Formation. The Zr/TiO2 (average = 0.110) and Y/TiO2 (average = 0.021) ratios in the footwall felsic volcanic rocks are consistent with known values for the Reids Brook member. The deposit consists of two concordant lenses of semi-massive to massive sulfides, approximately 150 m long and up to 9 m thick, which represent a fold repetition of a single exhalative horizon. The deposit contains a geologic resource of 136 000 tonnes grading 1.2% Pb, 1.0% Zn, 0.4% Cu, 90.9 g/t Ag, and 0.96 g/t Au; the deposit locally contains elevated Au (2.9 ppm) and Ag (320 ppm) contents. A laterally continuous iron formation that contains barite caps the deposit, and is gradational vertically and laterally into laminated siltstone. The exhalite confirms the stratiform nature of this deposit, but a large percentage of sulfides occur as late replacements of altered felsic fragmental rocks in the footwall. Abundant examples of colloform pyrite and perlitic and spherulitic textures in volcanic clasts are well preserved. The base- and precious-metal content of the Louvicourt deposit is atypical of the Bathurst Mining Camp (BMC). Reported assay data (n = 27) indicate an average Pb/Zn ratio of 2.6, the highest in the BMC (average = 0.39). Lead exhibits a strong Spearman Rank correlation (r&apos; = 0.92) with base metals throughout the sequence, indicating a preponderance of galena in both the stockwork and stratiform zones. The Ag and Au contents in this deposit are among the highest in the BMC and exhibit a Au-Ag- Cu-Pb association. Barite-rich exhalative pyrite exhibits a moderate Au correlation with Ag (r&apos; = 0.77; n = 10) and Cu (r&apos; = 0.76) and occurs in portions of the exhalative sulfides that are enriched in Pb. Chemical exhalative rocks are conformably overlain by trachy-andesitic volcaniclastic (possibly pyroclastic) rocks that are assigned to the Little River Formation. These are enriched in Nb (average = 38.4 ppm) and P2O5 (average = 0.17 wt.%), and have much lower Zr/TiO2 (average = 0.056) and Y/TiO2 (average = 0.0062) relative to rocks higher in the hanging wall. The intermediate volcanic rocks are conformably overlain by massive to pillowed basalt flows and related hyaloclastite that have Nb/Y = 0.60 and high TiO2 contents (average = 2.8 wt.%). This chemistry is consistent with rocks of the Brunswick Mines member (Little River Formation), except that these rocks are considerably enriched in P2O5 (average = 0.82 wt.%). This syngenetic exhalative deposit is unique for the BMC with a high Pb/Zn and elevated Au and Ag contents, as well as an epithermal signature (Sb-Ag-Au-Tl-Hg), analogous to high sulfidation volcanogenic massive sulfide deposits. Its intimate relationship with an emergent felsic dome (Flat Landing Brook Formation), chlorite-silicate-oxide-sulfide exhalite (locally hematitic), and the abundance of barite are classical features of many of the Kuroko deposits."

Jan 1, 2006

By T. H. Etsell, P. C. Holloway

Vanadium is concentrated in the fly ash which is produced as a solid waste from oil sands operations in northern Alberta. Although a process flowsheet using sodium chloride as a roasting reagent has been developed at the University of Alberta, recent studies examine the p otential o f p otassium o r c alcium s alts a s alternative reagents for roasting Suncor fly ash to recover vanadium. Suncor fly ash was roasted with CaO, Ca(OH)2, CaCO3, CaSO4.2H2O and KC1 at 750, 850 and 950°C. Water leach extractions for the calcium compounds were low (<45%); leaching with 100 g/L Na2CO3 gave maximum extractions of 56 to 69% at 950°C. Ash roasted with KCI behaved similarly to ash roasted with NaCl. These tests indicate that similar roasting conditions (25 to 30% KCI, 850°C, and 2 to 4h) could be used to achieve similar water leach extractions (75 to 85%). However, the lower solubility of KVO3 in solution, compared to NaVO3, would make the use of KCI instead of NaCl less attractive from a process and economic standpoint. Mineralogically, leucite (KAlSi3O8) was the predominant phase in ash roasted with KCl while, in crystalline samples of ash roasted with calcium compounds, anorthite (CaAl2Si2O8) and pseudobrookite (Fe2TiO5) were identified. Ash roasted below 950°C with the calcium compounds remained poorly crystalline.

Jan 1, 2004

By B. McLaughlin

"The Penna shaft is the deepest single-lift shaft in North America. Agnico-Eagle started sinking the Penna shaft in 1995 with a hoisting plant capable of hoisting 1800 t/d from a 2240-m deep shaft. Exploration success at depth led to the replacement of the existing double drum hoist by another double drum hoist capable of hoisting 7000 t/d. The use of another double drum hoist, instead of a Blair multi-rope winder, to hoist 24.5 t skips was only made possible by lowering the safety factor.This paper describes recent experiences at Penna and in South Africa, and examines the possibility of extending the double drum hoisting system to a depth of 3 km. IntroductionThe original Penna production hoist was a 4.88 m (16 ft) diameter double drum and single clutch machine. Béliveau (1996) and Scott (1996) have described this hoisting plant. In 1998, a decision was made to increase mining capacity from 1800 t to 4500 t of ore per day from the shaft bottom. Final capacity had to include an allowance of 1800 t of waste per day for future capital projects. While daily capacity was to be 6300 t, it would, by taking into account the different rock densities, be equivalent to hoisting 7000 t of ore.The steps taken to lower the safety factor were presented by McLaughlin and Scott"

Jan 1, 2004

By E. J. Marcotte

"INTRODUCTIONThe Upper Canada Mine is located at Dobie, approximately ten miles east of Kirkland Lake, Ontario.The mill contains Upper Canada's cyanide circuit and Upper Beaver's flotation circuit. The combined capacity is 590 tons per day consisting of 415 t.p.d. of Upper Canada gold ore and 175 t.p.d. of Upper Beaver copper-gold ore.The Upper Beaver ore is trucked five miles to the Upper Canada mine site.Crushing:The crushing circuit consists of primary, secondary and tertiary crushing employing one C .A. C. 15 in. x 24 in. Superior jaw crusher, one 4 ft. x 8 ft. Tyler-Niagara double deck screen, one 3 ft. Symons standard cone crusher and one 3 ft. Symons shorthead cone crusher.The -2 in. product from the jaw crusher is fed to the double deck screen. The+ 5/ 8 in. passes over the top deck to the 3 ft. standard cone crusher; the+ 3/ 16 in. material passes over the lower deck to the shorthead cone crusher. The - 3 / 16 in. material pas sing through the lower deck of screens is the product to the mill.The screens used prior to the installation of rubber screen cloths were: one 4 ft. x 4 ft. section with 3/ 4 in. square openings and one 4 ft. x 4 ft. section with 5/ 8 in. square openings on the top deck; two 4 ft. x 4 ft. sections with openings of 3/16 in. x 4 1/2 in. slot on the lower deck. The fine screens were positioned so that the 4 1/ 2 in. slots were parallel to the flow of feed.The crushing circuit is operated on a three shift per day basis by one operator per shift."

Jan 1, 1968

By G. E. Rowan

"DURING the dark ages, the cherished dream of chemists was to find a process for converting base metal into gold. Many a wealthy-but-gullible patron lost a fortune in the search. Men who work with metals today are a bit more realistic. I haven't heard of a metallurgist who expects to develop any one alloy that will resist all corrosive media. In the field of stain-less steels, there are about forty different types of alloys that are used where corrosion is a •problem.A stainless product is ordinarily selected because it offers one or more of the following qualities:(1) Resistance to corrosion (2) Resistance to oxidation at high temperatures (3) Good mechanical properties at room temperature (4) Good mechanical properties at high or low temperature (5) Attractive appearance (6) Ease of maintenanceToday we are interested in discussing the stainless steel family of alloys because of their .ability to resist corrosion. We• will not try to explain the Theory of Corrosion. Let us assume that, when surface potential and oxide formations are properly controlled, iron will resist attack in various chemi.cal solutions. The addition of alloying elements to iron does this for stainless steels. The principal stainless alloys used by various Canadian industries are listed in the accompanying Table."

Jan 1, 1959

By P. R. A. Andrews, R. K. Collings

"In cooperation with le Ministère de l&apos;Énergie et des ressources, Québec, le Centre de Recherches minérales, Sainte-Foy, Québec, and various silica producers, selected deposits of Quebec silica were identified in the southern region of the province and sampled to provide material for evaluation as glass and foundry sand by CANMET. The samples included both sandstone and quartz/quartzite. Head sample analyses ranged from 94.66% to 99.54% SiO2, 0.038% to 0.230% Fe2O3, and 0.16% to 4.51% Al2O3.Impurities included pyrite, iron oxides, and iron staining on quartz grains; carbonates as calcite; and alumino-silicates as clay and/or feldspar. Processing included size reduction to grain size, about 600 µm, by jaw, roll and cone crushers, and grinding in a muller-mixer. Removal of fines was achieved by attrition scrubbing and washing. Further removal of impurities was achieved by reverse flotation of iron oxide and alumino-silicate minerals employing both anionic and cationic collectors. Flotation resulted in a substantial improvement in the quality of most sands, the quartz concentrates analyzing 99.08% to 99.80% SiO2, 0.014% to 0.048% Fe2O3, and 0.06% to 0.49% Al2O3. Removal of iron oxide minerals was also investigated using the Sala HGMS. Iron oxide analyses of the non-magnetic fractions were comparable to the iron oxide analyses of the quartz concentrates obtained by flotation, 0.013% to 0.054% Fe2O3. On the basis of the samples submitted, silica from 5 of the 6 deposits studied has potential as source material for glass sand. Foundry tests showed that 3 of the 4 samples submitted for evaluation have potential as foundry sand."

Jan 1, 1987

By Jehan Rondot

Les trois intrusions alcalines de Suzorite en haute Mauricie, bien que non datees, son! sans doute d ,attacher aU)( nombreuses autres intrusions alcalines dispersees sur les blocks Grenvillia et Laurentia et datees de I 050 Ma =t= 10%, done reliees d l'orogene grenvilien. L 'utilisations de la Suzorite est liee d sa forte proportion de phlogopite (>50%). Le rapport Mg/Fey varie de 3 d 7. Sa mineralogie et sa composition particulieres (forte proportion de Mg, Ket H20) en font son attrait.

Jan 1, 1984

By Peter Wells, Adrian Sabau, Turgut Yalcin

"The nickel ores of Sudbury contain substantial amounts of the gangue mineral pyrrhotite (Fe7S&) which causes certain diflculties in the milling of these ores. This paper proposes a process called “magnetoflotation” as an effective means of dealing with pyrrhotite. The method reduces the pyrrhotite content of concentrates by applying a magneticjield on the path product as it leaves the flotation cell.Successful performance of magnetoflotation requires the optimization of several variables. In this study, three of the variables (air flowrate, collector concentration, pother concentration) were investigated by Box- Wilson experimental design, and others (magnet speed, grind size, pulp density, flotation time) were examined individually. The process was tested on a Falconbridge nickel ore, assaying 1.92% Ni, and under the best operating conditions, a concentrate was obtained with 13.56% Ni grade and 74.32% recovery in a single step. Further improvements to grade and recovery were possible by cleaning and scavenging. The same ore was also tested with conventional methods for comparison, and results indicated that magnetoflotation performed better.INTRODUCTION“Magnetoflotation” refers to the process of carrying out magnetic separation and flotation simultaneously within the same device, and is intended to prevent magnetic minerals from reporting to the froth products while non-magnetic minerals are being floated. Typical cases where this method might be beneficial include the processing of magnetite and nickel ores. Its use on magnetite ores has been reported elsewhere [Yalcin, 1992; Yalcin, 19931. This paper describes its application to nickel ores, more specifically to the nickel ore of Falconbridge Limited in Sudbury."

Jan 1, 1999

By S. R. McCutcheon, D. R. Lentz

"Abstract - The 12.1 Mt Brunswick No. 6 Zn-Pb-Cu-Ag massive sulfide deposit (New Brunswick, Canada) lies between two subaqueous felsic volcanic formations near the base of the Middle Ordovician Tetagouche Group. The footwall comprises rhyodacitic pyroclastic rocks (Nepisiguit Falls Formation), whereas the hanging wall comprises a sequence of rhyolitic flows, breccias, and hyaloclastites (Flat Landing Brook Formation), with an age difference of less than 3 m.y. The Brunswick No. 6 deposit is a proximal autochthonous deposit with a well-zoned massive sulfide body and a basal Cu zone that, at depth, develops into a stockwork stringer sulfide (feeder) system. The massive sulfides are capped sharply by a layered magnetite-chert unit that extends regionally beyond the deposit. The deposit has a keel shape (sheath) formed by the F1F2 interference pattern. The heterogeneous ductile deformation and upper greenschist-grade regional metamorphism has transposed many of the epigenetic stockwork structures and alteration within the host sequence. Hydrothermal alteration is much more extensive, both vertically and laterally, in the footwall (a few 100 m) than in the hanging wall (<100 m). Anomalies farther up in the hanging wall sequence seem to be associated with independent alteration systems related to the rhyolite domes. The least-altered footwall units exhibit keratophyric alteration (albite or adularia) and weak Mg enrichment (chlorite). More intense micaceous (sericite and Mg-rich chlorite) alteration occurs around the footwall sequence. The transposed stockwork stringer sulfides are typically composed of Fe-rich chlorite (± sericite, ± silica) with pyrite, pyrrhotite, chalcopyrite, arsenopyrite, and sphalerite. The (Fe2O3T+MgO)/(Na2O+K2O) and base metal alteration indices are the best practical lithogeochemical vectoring tools at this deposit. Sommaire - Le gîte de 12.1 Mt de sulfures massifs de Zn-Pb-Cu-Ag Brunswick No.6 est localisé entre deux formations volcaniques felsiques sous-marines situées près de la base du Groupe de Tetagouche d’âge Ordovicien Moyen. Le mur consiste en roches pyroclastiques rhyodacitiques (Formation de Nepisiguit Falls) tandis que le toit consiste en une séquence de coulées, de brèches et d’hyaloclastites de composition rhyolitique (Formation de Flat Landing Brook); la différence d’âge entre les deux est de moins de 3 m.y. Le gisement Brunswick No. 6 est un gîte autochtone proximal comprenant un corps de sulfures massifs clairement zoné ainsi qu’une zone cuprifère basale qui passe progressivement à un stockwork de filonnets de sulfure en profondeur (feeder). Les sulfures massifs sont abruptement surmontés d’une unité laminaire de chert et de magnétite dont l’extension par delà le gisement est régionale. Le gisement affecte la forme d’une quille (fourreau) résultant d’un patron d’interférence F1F2. Plusieurs des structures épigénétiques du stockwork et des patrons d’altération de l’encaissant ont été transposés par la déformation ductile hétérogène ainsi que par le métamorphisme régional au faciès des schistes verts. L’altération hydrothermale est beaucoup plus importante, tant verticalement qu’horizontalement, dans le mur (quelques 100 m) que dans le toit (<100 m). Les anomalies situées plus haut dans le mur semblent être reliées à des systèmes d’altération indépendants associés aux dômes de rhyolite. Les unités les moins altérées du mur une altération kératophyrique (en albite ou en adulaire) ainsi qu’un faible enrichissement en Mg (chlorite). Une altération en mica (séricite et chlorite magnésienne) plus intense est présente autour de la séquence du mur. Les sulfures du stockwork de filonnets transposés consistent typiquement en chlorite ferrifère (± séricite, ± silice) accompagnée de pyrite, de pyrrhotite, de chalcopyrite, d’arsénopyrite et de sphalérite. L’indice d’altération (Fe2O3T+MgO)/(Na2O+K2O) et l’indice des métaux usuels sont les outils d’exploration les plus appropriés dans ce gisement."

Jan 1, 2006

By Heikki Laurila, Sirkka-Liisa Jämsä-Jounela, Jarkko Karesvuori

"Artificial Intelligence includes excellent tools for the control and supervision of industrial processes. Several thousand industrial applications have been reported worldwide. Recently, the designers of the A1 systems have begun to hybridize the intelligent techniques, expert systems, fuzzy logic and neural networks, to enhance the capability of the A1 systems. Expert systems have proved to be ideal candidates especially for the control of mineral processes.As successful case projects, an expert system based on on-line classification of the feed type using neural data analysis is described in this paper. The essential feature of this expert system is the classification of different feed types and their distinct control strategies at the plant. In addition to the classification, the expert system has a database containing information about how to handle the determined feed type. This self-leaming database scans historical process data to suggest the best treatment for the ore type under processing. The system has been tested in the Outokumpu Finnmines Oy, Hitura mine. Other projects have been reported to be in progress.INTRODUCTIONIn the past ten years considerable researches have been done in the application of artificial intelligent methods in process industry. The technologies of fuzzy logic, neural networks and expert systems have received several thousand applications worldwide: monitoring and analysis of process operations, fault diagnosis, supervisory control, feedback control and scheduling and planning of operations. Recently, the designers of these systems have begun to hybridize these intelligent techniques to enhance the current capability of expert system. Complex signal processing, neural networks, fuzzy logic and rule-based systems are also implemented to develop new so-called smart or intelligent sensors, actuators or components. Field buses are playing a more and more important role in automation systems and in imbedded systems. The development of field buses has allowed the distribution of smart components over networks."

Jan 1, 2000

By W. H. MacLean, S. Liaghat

Abstract- The Key Tuffite is a thick (0.3 m to 6 m) and laterally extensive (-10 km) cherty, sulfide-bearing tuff unit in Archean greenstones in the Matagami mining district in northwestern Quebec. It lies at the contact of the Watson Lake Group and overlying Wabassee Group volcanic rocks, and is host to major Zn-Cu volcanogenic massive sulfide deposits. The tuff component is highly altered and its volcanic precursors are not identifiable by petrographie means. The tuff is mixed with a volcanic exhalative component comprising chert, carbonate and sulfides (pyrite, pyrrhotite, and minor sphalerite and chalcopyrite). The normative mineral composition of the Key Tuffite is 33% quartz, 28% sulfides, 16% sericite, 8% carbonate, 60Jo chlorite and 9% other minerals. In the vicinity of the Bell Allard and Orchan mines, the precursor tuff components are identified using immobile major and trace elements, as Watson Lake tholeiitic rhyolite (Zr/Y = 1.5 to 3.5, LaN/Ybn. = 1.7 to 2.8, Si02 = 72.5 ± 1.2 wt %, and Wabassee calc-alkaline andesite (Zr/Y =9, LaN/Ybn. = 4 to 8, Si02 = 56% to 65%). Immobile element computation techniques were used to calculate mass additions and losses in the conversion of the tuff to the Key Tuffite. Average net amounts of Fep3 (27% total iron), Si02 (14%), CaO (8%), S and K20 ( + 2%), were added, Na2O was removed (-2.8%), and MgO was over-all unchanged. Total net mass change was +63%, which comprises mainly exhalative additions, but also includes changes owing to hydrothermal alteration of the tuff component.

Jan 1, 1992

By Ralph W. Edie

"IntroductionTHE GOLDFIELDS AREA in northern Saskatchewan has be-come important in recent years because of numerous discoveries of pitchblende. The area is underlain by rocks of Precambrian age and, because of metamorphism and hydrothermal alteration, the geology in the vicinity of the pitchblende deposits is exceedingly complex and presents a challenge to all geologists •working in the district. This paper is a contribution to the geological literature of the area and presents a description of rock types, supplemented with petrographic, chemical, and spectrochemical data.Field work in connection with this paper was carried out during the summers of 1948, 1949, and 1950 while the writer was employed as assistant geologist for the Crown Corporation, Eldorado Mining and Refining ( 1944), Limited, Gold-fields area. Laboratory work was undertaken at the Massachusetts Institute of Technology during the winter months of 1949-50 and 1950-51 and extended through the summer of 1951.With the exception of SiO2and FeO, all of the new analyses ( 1) presented were carried out by quantitative spectrographic techniques under the supervision of Dr. L. H. Ahrens at M.I.T. Many of the techniques have only recently been developed at that Institute and detailed laboratory procedures have not yet been published."

Jan 1, 1952