Ontario Mineral Inventory

Ontario Geological Survey
Permanent Link to this Record: MDI52H09SE00004

Record: MDI52H09SE00004

General

Mineral Record Identification
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

Commodities

Primary Commodities: Gold

Secondary Commodities: Tungsten, Silver, Iron



Location

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.



Exploration History

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.


Assessment Work on File

Assessment Work on File
Office File Number Online Assessment File Identifier Online Assessment File Directory
63.4801 52H09NE0023 52H09NE0023

Geology

Province: Superior

Subprovince: Wabigoon

Belt: Beardmore-Geraldton

Geological Age: Archean  



Geology Comments

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).




Lithology

Lithology Data
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

Lithology Comments

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.




Mineralization

Mineralization and Alteration
Rank Mineral Name Class Economic Mineral Type Alteration Mineral Type Alteration Ranking Alteration Intensity Alteration Style
1ArsenopyriteEconomicOre
2GoldEconomicOre
3PyriteEconomicOre
4ScheeliteEconomicOre
5SphaleriteEconomicOre
6TetrahedriteEconomicOre
1QuartzEconomicGangue
CarbonateAlterationCarbonatization1UnknownDisseminated
SericiteAlterationSericitization2UnknownDisseminated
QuartzAlterationSilicification3UnknownDisseminated

Mineralization Comments

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.



Alteration Comments

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.




Mineral Record Details

Site Visit Information

Date: Jan 08, 1997

Geologist: B Nelson

Notes: The Beardmore-Geraldton Economic Geologist visited the minesite June 14, 1985 and July 4, 1985.



Production Data
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.

References

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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For detailed information regarding this mineral record please contact the Thunder Bay North Resident Geologist District Office