Ontario Geological Survey
Permanent Link to this Record:
MDI52B13SE00006
| Record Name(s) | Steep Rock - Hogarth - 1953, Steep Rock A Zone - 1953 |
|---|---|
| Related Record Type | Compound |
| Related Record(s) | |
| Record Status | Past Producing Mine Without Reserves or Resources |
| Date Created | 1979-Jul-19 |
| Date Last Modified | 2022-May-11 |
| Created By | |
| Revised By |
Primary Commodities: Iron
Secondary Commodities: Manganese
Township or Area: Freeborn
Latitude: 48° 49' 21.44" Longitude: -91° 38' 35.41"
UTM Zone: 15 Easting: 599592.76 Northing: 5408625.56 UTM Datum: NAD83
Resident Geologist District: Thunder Bay South
NTS Grid: 52B13SE
Point Location Description: Hogarth shaft
Location Method: Conversion from MDI
Access Description: North part of West Arm of former Steeprock Lake.
1891: H.L. Smyth noted the presence of hematite boulders in the vicinity of Steep Rock Lake. 1930-31: dip needle surveys were conducted by J.E. Marks and J. Cross. 1937-38: Steerola Exploration Ltd. carried out drilling. 1938-39: magnetometer and EM surveys were carried out. 1945: full-scale mining operations began by open pit from the Errington Mine and continued until 1952. 1953: Underground mining began from the Errington shafts. Open-pit mining began from the Hogarth Mine and continued until 1962. 1955-1961: Dredging operations at the Roberts mine, to establish the pit. 1958: Hogarth shaft was sunk, but has been on a standby basis since 1961. 1962: Open-pit mining began from the Roberts Mine, located between the Errington and Hogarth Mines. 1966: Steep Rock Iron Mines Ltd. entered into a joint venture agreement with The Algoma Steel Corporation Ltd., whereby Algoma acquired title to open-pit or in the Roberts and Hogarth Mines to a depth of 350 feet, with Steep Rock Iron Mines to deliver 22 million gross tons of pellets at a minimum annual rate of 1,100,000 gross tons. 1967: pellet plant was completed. 1972: Roberts pit was closed. Open pit mining resumed at Hogarth. 1973: underground operations at Errington ceased. 1979: Steep Rock mine closed. Production for the entire Steep Rock complex is recorded in MDI52B13SE00005.
Province: Superior
Subprovince: Wabigoon
Geological Age: Archean
| Rock Type | Rank | Composition | Texture | Relationship | Ironstone-unsubdivided | 1 | Is |
|---|---|---|---|---|
| Conglomerate | 2 | Near | ||
| Dolomitic Rock | 3 | Adjacent | ||
| Mafic Tuff | 4 | Ash Flow | Near |
Jun 21, 2018 (Therese Pettigrew) - The pre-Steep Rock complex is mainly granitic and dioritic gneiss. Above the gneiss, conglomerate occurs at intervals at the base of the Steep Rock Group. The greatest thicknesses of the gravel exceed 183 m and coincide with depressions in the pre-Steep Rock surface. Above the conglomerate is a dolomite formation up to 457 m thick. The ore zone is comprised of a lower Manganiferous Paint Member (non-ore) and the upper Goethite member (ore). The Manganiferous Paint Member is made up largely of incoherent to unctuous, rudely-banded to fragmental material that is commonly below ore grade. In places it holds more or less continuous highly siliceous bands which include massive chert, disconnected chert fragments, as well as white powdery siliceous material. The member is extremely variable in thickness, ranging from 1-305 m. The boundary between the Manganiferous Paint and the Goethite Members is quite abroupt. The Paint has more than 0.5% manganese and has iron/manganese ratios of less than 70 whereas the Goethite Member rarely has more than 0.3% manganese and the iron/manganese ratios are commonly greater than 200. Most of the Goethite Member is ore grade. Goethite is usually 2-5 times as abundant as hematite. The most characteristic feature of the ore is a ubiquitous breccia structure with hard, dark, angular lumps set in a lighter-coloured, porous, friable matrix. An irregular, stock-like body of material locally termed “Buckshot” occurs near the top of the Goethite Member at the Errington Mine. This rock is made up of dark pisolites and fragments of hematite in a lighter-coloured matrix containing kaolinite and gibbsite. Above the Goethite Member is the Pyrite Member, which has pyrite occurring in conformable lenses sporadically distributed along and near the contact between the ore zone and the overlying Ashrock Formation. The uppermost formation of the Steep Rock Group is the Ashrock Formation, which is nearly 275 m thick at the Errington Mine and contains pyroclastic rock and one or more basaltic lava flows (Shklanka, 1972).
| Rank | Mineral Name | Class | Economic Mineral Type | Alteration Mineral Type | Alteration Ranking | Alteration Intensity | Alteration Style |
|---|---|---|---|---|---|---|---|
| 1 | Goethite | Economic | Ore | ||||
| 2 | Hematite | Economic | Ore | ||||
| 1 | Kaolin | Economic | Gangue | ||||
| 2 | Quartz | Economic | Gangue | ||||
| 3 | Gibbsite | Economic | Gangue |
Jun 21, 2018 (Therese Pettigrew) - The mineral content from the ore zone has been calculated at 71.09% goethite, 20.98% hematite, 3.73% kaolin, 2.90% quartz, 0.36% pyrolusite, 0.24% vivianite, 0.19% magnesite, 0.18% calcite, and 0.06% pyrite (Shklanka, 1972). The goethite-hematite ore has a strike length of 6.1 km and is up to 91.4 m thick. Average of 1963 shipments yielded 59.6% Fe, 4.63% SiO2, and 0.03% S. Pyritic lenses occur over a strike length of 4.3 km and are up to 76 m wide and 510 m long. A weighted average of 600 m of drill intersections gave 38.6% Fe, 14.6% SiO2, and 24.3% S (Shklanka, 1968).
| Zone | Year | Category | Tonnes | Reference | Comments | Commodities |
|---|---|---|---|---|---|---|
| Steep Rock Mine | 1968 | Unclassified | 305721257 | Shklanka, 1968 | Reserves estimated at 337 million tons plus 273 million tons of lean ore averaging 30% Fe calculated to a depth of 518.16 m. | Iron 30 Percent |
Book - Canadian Mines Handbook 1980-1981
Publication Number: CMH 1980 Page: 256-257 Date: 1980
Author:
Publisher Name: Northern Miner Press
Location:
Map - Steep Rock Lake area, Rainy River District
Publication Number: M2217 Scale: 1:12,000 Date: 1972
Author: Shklanka R.
Publisher Name: Ontario Dept. of Mines and Northern Affairs
Location:
Mono - Iron deposits of Ontario
Publication Number: MDC011 Page: 297 Date: 1968
Author: Shklanka R.
Publisher Name: Ontario Dept. of Mines
Location:
MonoMap - Geology of the Steep Rock Lake Area, District of Rainy River
Publication Number: R093 Page: 72-79 Date: 1972
Author: Shklanka R., McIntosh J.R.
Publisher Name: Ontario Dept. of Mines and Northern Affairs
Location:
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