Ontario Geological Survey
Permanent Link to this Record:
MDI52H09SE00004
| Record Name(s) | Leitch Gold Mine - 1936, Nipigon Hematite Ore Company - 1910, Lake Superior Iron Ore Company - 1901 |
|---|---|
| Related Record Type | Partial |
| Related Record(s) | |
| Record Status | Past Producing Mine Without Reserves or Resources |
| Date Created | 1984-Nov-02 |
| Date Last Modified | 2023-Feb-06 |
| Created By | |
| Revised By |
Primary Commodities: Gold
Secondary Commodities: Tungsten, Silver, Iron
Township or Area: Eva
Latitude: 49° 37' 30.63" Longitude: -88° 2' 7.7"
UTM Zone: 16 Easting: 425216 Northing: 5497472 UTM Datum: NAD83
Resident Geologist District: Thunder Bay North
NTS Grid: 52H09NE, 52H09SE
Point Location Description: Minesite
Location Method: AMIS Site Visit
Access Description: The minesite is located 4 km west-northwest of the Beardmore townsite. The property is readily accessible by travelling 1.5 km north from Beardmore and turning west on secondary Highway 580. The Leitch mine site is situated 7.5 km along this road.
1901-1909: Claims were staked for iron deposits. 1910-1923: Iron exploration cont. Diamond drilling outlined reserves of 3.5 million tons 33% Fe and 5 million tons 30% Fe. 1934-35: Gold discovered on the adjoining property to the south. Shaft sinking began the same year. 1936: A 3-compartment vertical shaft was completed to 160 m. Cross-cutting, drifting and raising commenced. No. 1 vein fully developed on the first 3 levels by year end. Const of a 75 t/day mill began. 1937: First gold brick poured in Feb. Underground dev't con't. 1938: Underground dev’t con't on six veins. Drilling con't. 1939: 4 new veins discovered and explored. 1942: Dev’t work reduced by 25% as a result of manpower shortage due to the war. Scheelite ore discovered and 31.6 tons of ore were hand sorted and stockpiled. 1943: Lateral dev’t discontinued due to manpower shortage. 1944: Operations curtailed. Mill operated on stockpile feed. 1946: Normal operations resumed. 1947-1961: Underground dev’t con’t in the form of shaft sinking, winze extension, cross-cutting, and drifting. Diamond drilling carried out regularly. 1962: Est. that ore reserves were good for 2 more years. Sub-marginal material on the 30th level west of the main ore zone was thought to be mineable and was to be tested. 1963: Dev’t cont. Drilling failed to prove ore reserves below the 30th level. 1965: Mine and mill shut down May 15, after 30 years of continuous gold production. 1966-68: Clean up initiated. 1980-81: Teck Exploration screened material from the Leitch dump and shipped it to Lamaque for processing. A grid was cut, and VLF-EM and mag surveys and overburden drill sampling (393 holes) was performed. 28 DDH totalled 2,926m. 1983: Teck leased the former Pan-Empire Joint Venture custom gold mill in Beardmore to process the old Leitch Mine dump. 1984: Teck cont to feed the mill with dump material.
| Office File Number | Online Assessment File Identifier | Online Assessment File Directory |
|---|---|---|
| 63.4801 | 52H09NE0023 | 52H09NE0023 |
Province: Superior
Subprovince: Wabigoon
Belt: Beardmore-Geraldton
Geological Age: Archean
Dec 07, 2005 (B Nelson) - The Leitch Mine property lies within the southern portion of the Wabigoon Sub-province in the Beardmore Geraldton Belt. This belt is further sub-divided into the Southern Metavolcanic Sub-belt and the Southern Metasedimentary Sub-belt. It is within the latter that the property is situated. This sub-belt is primarily sedimentary rocks, but contains interfingerings of basic to intermediate volcanic rocks. 94% of the gold produced in the Beardmore-Geraldton camp is from the Southern Metasedimentary Sub-belt. East-trending iron formations, up to 244 m wide, occur in the sediments. A prominent flat-lying diabase sheet, dipping 10-15 degrees to the west was intersected in the Leitch No. 1 shaft. This 'sill' is interpreted to be the same unit that intersects the Northern Empire ore zone 7 km to the southeast. Isoclinal folding and tight drag folding in the Beardmore and Geraldton areas, specifically observable in the iron formation, appear necessary controls for ore structure developments. Drag folds and ore-bearing structures throughout the belt plunge westward at 35 to 40 degrees. Gold mineralization occurs in two sets of narrow quartz veins occupying fractures in the greywacke; those parallel to the fold axial plane in shear zones and those nearly perpendicular to the axial plane. These veins are strongly sheared, and contain transverse, healed, tension gashes. The depth continuity of the veins normally exceeds the horizontal continuity by a multiple of 15. The veins range in width from 10 cm to 45.7 cm on avg., and many parts of the veins are contorted with thickened portions in the bends of folds. They consist mainly of light grey to white quartz with common chlorite-sericite banding parallel to the walls, representing a 'crack-seal' texture. Five veins have been mined. They are located on the flank of an anticline which apparently controlled their strike, dip and plunge (50 degrees W).
| Rock Type | Rank | Composition | Texture | Relationship | Sandstone | 1 | Greywacke | Sheared | Host |
|---|---|---|---|---|
| Conglomerate | 2 | Near | ||
| Claystone | 3 | Argillite | Near | |
| Ironstone-unsubdivided | 4 | Mag-Hem-Ch | Near | |
| Quartz Diorite | 5 | Quartz-Diorite | Near | |
| Diabase | 6 | Diabase | Near | |
| Vein | 7 | Quartz | Host |
Dec 07, 2005 (B Nelson) - Rocks within the Southern Metasedimentary Sub-belt overlie those of the Southern Metavolcanic Sub-belt (tops to the north) and are dominated by turbidite sequences consisting of Archean greywacke, conglomerate, argillite, mag-hem-ch iron formation, quartz diorite-gabbro intrusions and proterozoic diabase dykes. The metasediments are mainly thick-bedded uniform greywacke with associated narrow slaty bands and thin interbeds or lenses of argillite and pebble conglomerate. Iron formations occur in the sediments and vary from a well-banded jasper-hematite with associated magnetite to hematite-bearing red argillite. The metavolcanics in the area of the mine site are fine-grained and vary in color from light grey to green. Ash-fall tuffs and flow rocks predominate.
| Rank | Mineral Name | Class | Economic Mineral Type | Alteration Mineral Type | Alteration Ranking | Alteration Intensity | Alteration Style |
|---|---|---|---|---|---|---|---|
| 1 | Arsenopyrite | Economic | Ore | ||||
| 2 | Gold | Economic | Ore | ||||
| 3 | Pyrite | Economic | Ore | ||||
| 4 | Scheelite | Economic | Ore | ||||
| 5 | Sphalerite | Economic | Ore | ||||
| 6 | Tetrahedrite | Economic | Ore | ||||
| 1 | Quartz | Economic | Gangue | ||||
| Carbonate | Alteration | Carbonatization | 1 | Unknown | Disseminated | ||
| Sericite | Alteration | Sericitization | 2 | Unknown | Disseminated | ||
| Quartz | Alteration | Silicification | 3 | Unknown | Disseminated |
Dec 07, 2005 (B Nelson) - Gold is often associated with chlorite-sericite occurring in thin fractures within the quartz veins, as well as minor sulphides. Some visible gold occurs on surface and in parts of the mine, although much of the ore did not contain visible quantities. The overall gold content was found to be greatest in the narrowest parts of the veins. Halite is also present as some faults up to 20 cm thick. Scheelite is relatively abundant and appears to form at the junction of cross-cutting faractures rather than within individual fractures. The wallrock adjacent to the mineralized quartz veins is reported to be unmineralized. No assays of wallrock appear among the old data.
Dec 07, 2005 (B Nelson) - In the vicinity of the Leitch gold veins, strong carbonate-sericite alteration exists in the greywacke. This zone was not defined in the field. However, it is large (91m square) and is most prominant stratigraphically below the quartz veins. A total of 3,598 tons of ore was mined at an average grade of 0.56 oz/ton Au from outside the main vein system (No. 16 and some associated veins) on the 8th level. About 15% of the ore was mined by shrinkage stoping in the wider sections of the mine, and the balance by resuing methods. 399 oz of gold and 27 oz of silver were produced from the mill cleanup during 1966-68.
Date: Jan 08, 1997
Geologist: B Nelson
Notes: The Beardmore-Geraldton Economic Geologist visited the minesite June 14, 1985 and July 4, 1985.
| Year | Tonnes | Commodities | Reference | Comment |
|---|---|---|---|---|
| 1968 | 927461 |
Silver 31802 Ounces Gold 861982 Ounces |
OFR5630, p. 328 | Last year of Production: 1968. Mine operation: 1936-1968. Total Production (tons milled) = 1,022,351 (927,461 tonnes). Au = 861,982 oz @ 0.92 oz/t. Ag = 31,802 oz. |
Map - Beardmore-Nezah gold area, District of Thunder Bay, Ontario
Publication Number: ARM37K Scale: 1:63,360 Date: 1998
Author: Langford G.B.
Publisher Name: Ontario Dept. of Mines
Location:
Map - Sturgeon River gold area, District of Thunder Bay, Ontario
Publication Number: ARM45A Scale: 1:63,360 Date: 1998
Author: Bruce E.L., Laird H.C.
Publisher Name: Ontario Dept. of Mines
Location:
Article - 1981 report of the Thunder Bay Resident Geologist
Publication Number: MP101.004 Page: 61 Date: 1997
Author: McIlwaine W.H., Fenwick K.G., Scott J.F., Mason J.K., Schnieders B.R., Kristjansson F.J., Speed A.A., Bourdages H.M.
Publisher Name: Ontario Geological Survey
Location:
Map - Tashota-Geraldton sheet, geological compilation series, Thunder Bay and Cochrane districts
Publication Number: M2102 Date: 1997
Author: Pye E.G., Harris F.R., Fenwick K.G., Baillie J.
Publisher Name: Ontario Dept. of Mines
Location:
Map - Summers Township, District of Thunder Bay
Publication Number: P0602 Scale: 1:15,840 Date: 1998
Author: Mackasey W.O.
Publisher Name: Ontario Dept. of Mines
Location:
Map - Compilation series, Lake Nipigon sheet, District of Thunder Bay
Publication Number: P0257 Scale: 1:126,720 Date: 1984
Author: Stott G.M., McConnell C.D., Mason J.K.
Publisher Name: Ontario Geological Survey
Location:
Mono - Gold occurrences, prospects, and deposits of the Beardmore-Geraldton area, districts of Thunder Bay and Cochrane
Publication Number: OFR5630 Page: 314-328 Date: 1986
Author: Mason J.K., White G.D.
Publisher Name: Ontario Geological Survey
Location:
File - Resident Geologist Mineral Deposit Files
Publication Number: Min Dep Date:
Author:
Publisher Name:
Location: Thunder Bay RGP
Book - General structural relationships of ore deposits in the Little Long Lac-Sturgeon River area; In: Structural Geology of Canadian Ore Deposits, Jubilee Volume
Publication Number: Page: 377-384 Date: 1948
Author: Horwood, H.C.
Publisher Name: Canadian Institute of Mining, Metallurgy and Petroleum
Location:
Part - The western part of the Sturgeon River area (Sturgeon R.-Beardmore section)
Publication Number: ARV45-02.002 Page: 101-105 Date: 1998
Author: Laird H.C.
Publisher Name: Ontario Dept. of Mines
Location:
Folio - Poplar Point area (Dorothea Township), District of Thunder Bay
Publication Number: GDIF186 Date: 1997
Author: Thunder Bay RGO
Publisher Name: Ontario Geological Survey
Location:
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