Ontario Mineral Inventory

Ontario Geological Survey
Permanent Link to this Record: MDI42L11NW00006

Record: MDI42L11NW00006

General

Mineral Record Identification
Record Name(s) Sulmac Exploration DDH 61-7 - 1958, Skibi Lake Iron Occurrences - 1970, Stewart Lake - 1961
Related Record Type Partial
Related Record(s)
Record Status Prospect
Date Created 1980-May-15
Date Last Modified 2022-Jul-20
Created By
Revised By

Commodities

Primary Commodities: Iron



Location

Township or Area: Stewart Lake Area

Latitude: 50° 42' 52.53"    Longitude: -87° 24' 41.23"

UTM Zone: 16    Easting: 470951.7   Northing: 5618168.02    UTM Datum: NAD83

Resident Geologist District: Thunder Bay North

NTS Grid: 42L11NE, 42L11NW

Point Location Description: drill collar for DDH 61-7

Location Method: Data Compilation



Exploration History

1957-58: Panther Mining Company Limited – airborne geophysics. 1958-59: Sulmac Exploration Services Ltd. – DD-3-1268 ft 1961: Stewart Lake Iron Mines – DD-1-603 ft, bulk sample


Assessment Work on File

Assessment Work on File
Office File Number Online Assessment File Identifier Online Assessment File Directory
11 42L11NW0007 42L11NW0007
18 42L11NW0012 42L11NW0012
17 42L11NW0011 42L11NW0011

Geology

Province: Superior

Subprovince: English River

Terrane: English River Basins

Belt: Melchett Lake

Geological Age: Archean  



Lithology

Lithology Data
Rock Type Rank Composition Texture Relationship
Ironstone-unsubdivided 1 Is
Claystone 2 Argillite Adjacent
Gneiss-Unsubdivided 3 Biotite Adjacent

Lithology Comments

Aug 15, 2014 (A Wilson) - The Stewart Lake-Skibi Lake occurrences consist of two bands of iron formation, the main one which extends approximately 31 miles from east of Tennant Lake to the Little Current River on the east. The second band is found only in the Melchett Lake area - it extends over a strike length of about 8 miles. The two bands are separated by about 2,000 feet of biotite quartz- feldspar schist (metagreywacke). The older, smaller band consists of "cyclic layers of magnetite, schist, and often quartz". The major unit has a basal band of iron formation separated from an upper, higher grade band by 50-150 feet of biotite-quartz-feldspar schist. The iron formation bands themselves vary from 100 to 400 feet thick in the Melchett Lake area. They are coarsely to finely layered, oxide-facies iron formation with magnetite-rich beds up to 12-18 inches thick and quartzite or cherty interbeds up to 8 to 10 inches thick where observed. As one proceeds eastwards along strike, the two bands of iron formation grade from oxide facies to sulphide facies.




Mineralization

Mineralization and Alteration
Rank Mineral Name Class Economic Mineral Type Alteration Mineral Type Alteration Ranking Alteration Intensity Alteration Style
1HematiteEconomicOre
2MagnetiteEconomicOre

Mineralization Comments

Aug 15, 2014 (A Wilson) - Hematite is more abundant, and the magnetite-hematite ratio of 2:1 The iron formation is bounded by sedimentary rocks. Pegmatites are not abundant. The formation is relatively continuous, but as a series of lenses connected by thinner bands. Mill testing of a 500 lb sample returned a concentrate averaging 62-64% Fe, 7% SiO2



Mineral Record Details

References

Map - Compilation series, Ogoki Lake sheet, Thunder Bay and Cochrane districts

Publication Number: P0274 Scale: 1:126,720    Date: 1997

Author: Stott G.M., McConnell C.D., Mason J.K.

Publisher Name: Ontario Geological Survey

Location:


Mono - Operation Fort Hope

Publication Number: MP042 Page: 22, 55-56  Date: 1970

Author: Thurston P.C., Carter M.W.

Publisher Name: Ontario Dept. of Mines and Northern Affairs

Location:


Report an Error

We are continuously updating our assessment file / technical report information. If you notice errors in the data, please contact us.


Terms of Use

Please review our Terms of Use agreement for this data product.


Ministry Contact Information

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