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Labrador City - Carol, Wabush - Scully, Mont Wright, Bloom Lake |
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Labrador & Newfoundland, Canada |
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Fe Mn
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Super Porphyry Cu and Au
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IOCG Deposits - 70 papers
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All papers now Open Access.
Available as Full Text for direct download or on request. |
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The Labrador City - Carol, Wabush - Scully and Mont Wright iron mines are three separate operations developed within the Labrador City area straddling the border between Labrador-Newfoundland and Quebec in eastern Canada, some 300 km due north of the Gulf of St Lawrence port of Sept Iles. This group of deposits is located approximately 200 km south of the similar Schefferville - Knob Lake Range iron mines (see the separate record).
These deposits were operated by the Rio Tinto group company Iron Ore Company of Canada (IOC); Cleveland Cliffs for Wabush Mines; and Québec Cartier Mining Company (QCM) respectively (in 2006). IOC and Wabush Mines share a 420 km rail line to Sep Iles, while QCM has a separate rail connection to their facility at Port Cartier. All three market both concentrates and pellets.
All three deposits are hosted within Paleoproterozoic iron formation of the New Quebec Orogen.
The New Quebec Orogen (formerly called the Labrador Trough) is an approximately 1000 km long Palaeoproterozoic fold and thrust belt developed along the collision zone between the largely Archaean Rae Province to the northeast and the Archaean Superior Province to the south-west. The 'Wabush - Labrador City' district is in the southern part of the New Quebec Orogen, south of the Grenville Front, in the Grenville Orogenic Belt, where the rocks have been subjected to complex folding during two Proterozoic deformational periods - the 1.8 Ga Hudsonian and 1.0 Ga Grenvillian orogenies.
The principal iron formation within the New Quebec Orogen, the Sokoman Formation (and locally named correlates), occurs throughout the length of the New Quebec Orogen, forming one of the most extensive iron-formations in the world. The Sokoman Formation has been dated at 1880 ±2 Ma. The host in the 'Wabush - Labrador City' district is the Wabush Iron Formation, a metamorphosed and deformed equivalent of the Sokoman Formation.
The iron formation that comprises the ore has a medium to coarse grained (up to 2 mm) texture and are composed of specular hematite and magnetite in a granular quartz matrix which may be easily concentrated. The main gangue mineral in the Wabush Iron Formation is quartz, comprising around 50% of the iron formation which overall are a specularite schist. Folding has led to thickening and repetition of the iron formation, but imposes complex, small scale (10 to 15 m amplitude) folding patterns that may complicate mining.
The Wabush Iron Formation is composed of five members totalling more than 300 m in thickness. Each of these members can be correlated on a mine scale and have relatively consistent contents of iron, manganese and other elements throughout individual mines.
Two of the five members have insufficient iron content to be of economic interest, namely the 12 m thick Middle Quartzite and the Basal Silicates which define the base of the Wabush Iron Formation. In the latter, the iron content is held within silicates and is not recoverable. The iron in the Upper (135 m), Middle (120 m) and Lower (70 m) Members is dominantly specular hematite with lesser magnetite. Small quantities of iron silicates such as grunerite and carbonates such as ankerite are not recovered in the final concentrates. The details in this paragraph are for the Wabush - Scully mine.
At Wabush - Scully, each of these three mineralised members includes bands of mostly waste - the middle of three units that constitute the Lower Member, one of the four that make up the Middle Member, while two of the three units of the Upper Member are waste and remaining band is mixed ore and waste. In addition to iron, the ore bands contain Mn, with 2.7% in the Lower Member units, 1.6 to 1.3 (decreasing up wards) in the Middle Member, and 0.8% Mn in the Upper Member (Farquharson, 2006).
Unlike the IOC Carol deposit, 15 km to the north, the Scully deposit has been subjected to deep weathering and oxidation that reaches depths in excess of the final pit outline in many areas. This has converted what would otherwise be ore into waste through the formation of geothite which cannot be tolerated in the concentrate. This particularly applies to the Upper Member.
The Mont-Wright deposit is 30 km SW of Scully, and 15 km WSW of the toen of Fremont, and is hosted by the equivalent Bloom Lake ironstone. The host ironstone is 300 m thick unit, which can be traced over a 2000 m strike length and has been explored to a depth of 300 to 400 m below the surface. It consists of tabular to folded and anastomosing bands of specular hematite, magnetite and intercalated actinolite in a dominantly quartz matrix. There is little variation in the total iron content of the deposit, although there are wide differences in the percentages of magnetite and actinolite over its strike extent, with only minor intercalated layers of actinolite at one end while at the other the actinolite-rich sections are finely interwoven with the magnetite and specularite (Mining Journal, 13/10/06).
The Bloom Lake deposit is 18 km NNE of Mont-Wright, and 12 km WNW of Fremont, and is also hosted by the equivalent Bloom Lake ironstone.
Published reserve and resource figures are as follows:
IOC - Labrador City
Reserve, 2006 - 427 Mt @ 65.0% Fe (Rio Tinto Ann. Rept., 2006),
Total Resource, 2006 - 1433 Mt @ 65.0% Fe (Rio Tinto Ann. Rept., 2006),
In 2005 IOC produced 13.3 Mt of pellets and 2.3 Mt of concentrate.
Reserve, 2012 - 555 Mt @ 65.0% Fe (Rio Tinto Ann. Rept., 2012),
Total Resource, 2012 - 3.088 Gt @ 38.1% Fe (Rio Tinto Ann. Rept., 2012).
Proved + Probable Reserve 31 December, 2021 - 483 Mt @ 65.0% Fe, 3.2% SiO2 (Rio Tinto Ann. Rept., 2021),
Measured + Indicated Resource 31 December, 2021 - 786 Mt @ 39.0% Fe, 37.1% SiO2, 0.2% Al2O3, 0.03% P (Rio Tinto Ann. Rept., 2021),
Inferred Resource 31 December, 2021 - 895 Mt @ 38.3% Fe, 37.8% SiO2, 0.2% Al2O3, 0.03% P (Rio Tinto Ann. Rept., 2021),
NOTE: Rio Tinto Resources are exclusive of Reserves. Reserves (and Resources from 2006) with grades of 65% Fe represent tonnages of marketable product, i.e., pellets and concentrate, that will be produced after beneficiation of the lower grades similar to those quoted in Resources.
Wabush - Scully Reserve, 2005 - 168.7 Mt @ 35.8% Fe (Farquharson, 2006),
Wabush - Scully, Resource, 2005 - Not calculated,
Production in 2006 was to be 11.63 Mt of ore and 5.92 Mt of waste, from which it was planned to produce 6 Mt of concentrate.
Wabush proved + probable reserves (Cliffs Natural Resources Annual Report, 2012) in 2012 were: 209.0 Mt @ 35.1% MagFe
This represents 66.1 Mt of 65% Fe pellets.
Mont-Wright
Proved + Probable Reserve, 2005 - 579.6 Mt @ 30% Fe (Mining Journal, 13/10/06),
Measured Resource, (to 75 m depth) 2005 - 488.5 Mt @ 29.91% Fe (Mining Journal, 13/10/06),
Indicated resource, (to 75-150 m depth) 2005 - 149.2 Mt @ 29.29% Fe (Mining Journal, 2006).
Proved + Probable Reserve, 31 December 2020 - 2308 Mt @ 29.3% Fe (ArcelorMittal 2020 Annual Report),
Measured + Indicated Resource - 3814 Mt @ 29.0% Fe (ArcelorMittal 2020 Annual Report),
Inferred resource - 1783 Mt @ 28.8% Fe (ArcelorMittal 2020 Annual Report).
NOTE: ArcelorMittal Resources are exclusive of Reserves.
Bloom Lake
Proved + Probable reserves (Cliffs Natural Resources Annual Report, 2012) in 2012 were: 1034.5 Mt @ 28.6% MagFe
This represents 355.8 Mt of 66% Fe, 0.011% P, 0.2% Al2O3 concentrate.
The most recent source geological information used to prepare this decription was dated: 2009.
This description is a summary from published sources, the chief of which are listed below.
© Copyright Porter GeoConsultancy Pty Ltd. Unauthorised copying, reproduction, storage or dissemination prohibited.
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Seymour, C., Winter, L., O’Driscoll, J. and Butler, R., 2009 - Renewed Exploration in Canada’s Premier Iron Ore District – Labrador West: in Proceedings, Iron Ore 2009 Conference, 27-29 July 2009, Perth, Western Australia, The Australasian Institute of Mining and Metallurgy, Melbourne, pp. 161-170
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Porter GeoConsultancy Pty Ltd (PorterGeo) provides access to this database at no charge. It is largely based on scientific papers and reports in the public domain, and was current when the sources consulted were published. While PorterGeo endeavour to ensure the information was accurate at the time of compilation and subsequent updating, PorterGeo, its employees and servants: i). do not warrant, or make any representation regarding the use, or results of the use of the information contained herein as to its correctness, accuracy, currency, or otherwise; and ii). expressly disclaim all liability or responsibility to any person using the information or conclusions contained herein.
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