Ontario Mineral Inventory

Ontario Geological Survey
Permanent Link to this Record: MDI42E12NW00005

Record: MDI42E12NW00005

General

Commodities

Primary Commodities: Gold

Secondary Commodities: Silver, Copper

Location

Township or Area: Irwin

Latitude: 49° 44' 45.95"    Longitude: -87° 47' 20.69"

UTM Zone: 16    Easting: 443152   Northing: 5510700    UTM Datum: NAD83

Resident Geologist District: Thunder Bay North

NTS Grid: 42E12NW, 42E13SW

Point Location Description: AMIS location

Location Method: Conversion from MDI

Exploration History

1934: E. Rigotte staked the claims. In November, all interest was transferred to Macjoe Sturgeon Gold Mines Ltd., who carried out stripping, blasting, and trenching. 1935: Macjoe Sturgeon Gold carried out stripping and trenching, and drilled 30 DDH totalling 1524 m. 1944-45: Sturgeon River Gold Mines Ltd. staked the property and carried out a magnetometer survey and diamond drilling. 1972-73: Jupiter Minerals Inc. was formed and carried out trenching and sampling, and EM and magnetometer surveys. 1975: Jupiter Minerals changed its name to Phoenix Gold Mines Ltd. 1984-85: Phoenix Gold Mines carried out magnetometer, VLF and IP surveys, geological mapping, sampling, stripping and trenching, as well as a diamond drill program. 1986: Phoenix Gold Mines carried out stripping. 1988: Placer Dome optioned the property and carried out diamond drilling before dropping the option. 2007: Laurion Mineral Exploration Inc. acquired the property. 2010: Laurion carried out mapping and sampling.

Assessment Work on File

Geology

Province: Superior

Subprovince: Wabigoon

Terrane: Eastern Wabigoon

Belt: Onaman-Tashota

Geological Age: Archean  

Lithology

Mineralization

Mineralization Comments

Oct 29, 2018 (Therese Pettigrew) - Veins No. 21, 23 and 24 occur entirely within the granodiorite; vein No. 25 passes from granodiorite into rhyolite flows and agglomerate. On surface, vein No. 21 has a maximum width of 6 inches and has been exposed for 250 feet. Diamond-drill holes in low ground to the south, however, have indicated the extension of the vein in this direction for another 150 feet. The quartz is strongly fractured parallel to the strike and contains varying quantities of pyrite, chalcopyrite, and galena, and a little visible gold. Vein No. 23 has a maximum width of 12 inches and an average width of 6 inches; it has been exposed for about 300 feet. The quartz is strongly fractured parallel to the strike and carries moderate quantities of pyrite and galena. Thin flakes of visible gold occur in tiny fractures near the margins of the vein. Vein No. 24 is a lens-like mass of quartz with a maximum width of 6 feet but narrowing down to 2 inches in places. The quartz is rusty in spots and carries moderate quantities of pyrite concentrated mainly in longitudinal, sericite-filled fractures parallel to the strike. The gold values here are said to be low. Vein No. 25 is the most important thus far exposed on the property both as regards magnitude and mineralization. Like most of the veins in this area it is narrow but remarkably persistent as to length being exposed in a long trench for more than 1,000 feet. It pinches and swells in characteristic manner, ranging from 6 to 18 inches in width over much of its length, but widening to 3 feet in places. The average sampling width is probably about 10 inches. Where the vein passes from the granodiorite into the rhyolite fragmental, the wall rock for 2 feet on either side of the vein is perceptibly altered to a reddish, cherty, well-pyritized type, which, however, is said to yield no gold values. In places, fairly heavy concentrations of pyrite, chalcopyrite, galena, and sphalerite were observed. Specks of visible gold are commonly seen, especially where galena and sphalerite are prominent constituents of the vein matter (Laird, 1937). Samples taken in 1935 on the No. 25 vein assayed 0.16-0.65 gpt Au. Bulk samples taken from the No. 21 vein returned assays of 1.15 opt Au, 0.21 opt Ag, and 0.04% Cu. Bulk samples taken on the No. 25 vein assayed up to 1.58 opt Au, 1.81 opt Ag, and 0.02% Cu. A bulk sample taken on the No. 23 vein assayed 0.44 opt Au, 1.43 opt Ag, and 0.02% Cu (Speed and Craig, 1992). Highlights from Laurion’s 2010 sampling program include: 124 g/t gold with 79 g/t silver, 24 g/t gold, 6.1 g/t gold with 85 g/t silver, 5.72 g/t gold with 22 g/t silver, 3.45 g/t gold, 2.52 g/t gold, 1.05% zinc with 0.40 g/t gold (AFRI 20000013492).

Mineral Record Details

References

Map - Dorothea, Sandra and Irwin townships, Thunder Bay District

Publication Number: M2294 Scale: 1:31,680    Date: 1974

Author: Mackasey W.O.

Publisher Name: Ontario Division of Mines

Location:

Mono - Beardmore-Geraldton historical research project

Publication Number: OFR5823 Page: 238-246  Date: 1992

Author: Speed A.A., Craig S.

Publisher Name: Ontario Geological Survey

Location:

Book - GDIF 42E12NW (unpublished)

Publication Number: GDIF Date: 1988

Author: Ontario Geological Survey

Publisher Name: Ontario Geological Survey

Location:

Mono - Gold deposits of Ontario, part 1, districts of Algoma, Cochrane, Kenora, Rainy River, and Thunder Bay

Publication Number: MDC013 Page: 277  Date: 1971

Author: Ferguson S.A., Groen H.A., Haynes R.

Publisher Name: Ontario Dept. of Mines and Northern Affairs

Location:

File - Resident Geologist Mineral Deposit Files

Publication Number: Min Dep Date: 1996

Author:

Publisher Name:

Location: Thunder Bay RGP

MonoMap - Geology of Dorothea, Sandra, and Irwin townships, District of Thunder Bay

Publication Number: R122 Date: 1975

Author: Mackasey W.O.

Publisher Name: Ontario Division of Mines

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