Ontario Mineral Inventory

Ontario Geological Survey
Permanent Link to this Record: MDI52A05SE00009

Record: MDI52A05SE00009

General

Commodities

Primary Commodities: Silver, Cobalt

Secondary Commodities: Copper, Zinc, Fluorite, Barite, Lead

Location

Township or Area: O'Connor

Latitude: 48° 19' 9.97"    Longitude: -89° 38' 22.3"

UTM Zone: 16    Easting: 304329.66   Northing: 5355172.45    UTM Datum: NAD83

Resident Geologist District: Thunder Bay South

NTS Grid: 52A05SE

Point Location Description: Transfer

Location Method: Conversion from MDI

Exploration History

1884: O. Daunais discovered the vein. 1885: The property was acquired by American investors and development work began. 1887: rich ore was discovered and by July, a large tonnage was proved. 1891: mining ceased due to the drop in silver prices. Workings consist of 2 vertical shafts, 4 levels, and a system of adits and winzes developed to operate on the vein for a length of 900' and a depth of 400'. A crosscut extends 330' and a diamond drill hole was bored 800' below the lowest level to intersect Keewatin rocks. 1907: Mine was dewatered and a new mill constructed. The new mill was found to be faulty and the property closed again. 1927: Mine was dewatered to the 200’ level and samples were taken. The most intensive work of note on the property was in the 1950s and 1960s. This work included geophysics, mapping, drilling, dewatering the Beaver Mine and sampling, notably by Cairngorm Mines. Minor intermittent exploration was also done in the 1970s and 1980s. 1995-96: Cairngorm conducted prospecting, stripping, trenching. 1997: Cairngorm conducted stripping and soil sampling. 2017: Honey Badger Exploration signed a letter of intent to option the property from Cairngorm Mines. 2018: Honey Badger carried out airborne magnetic and electromagnetic surveys, prospecting and sampling, and drilled 8 DDH totalling 1585 m.

Assessment Work on File

Geology

Province: Southern

Formation Group: Animikie Group

Geological Age: Paleoproterozoic  

Lithology

Lithology Comments

Jan 29, 2018 (Therese Pettigrew) - The regional geology consists of 300 to 400' of black, sulphidic, graphitic shale ("Rove Formation") overlying iron formation ('Gunflint Formation'). Both are Aphebian (Late Precambrian) in age and dip gently to the south. Archean basement rocks (granite, greenstone, etc.) underlie the sediments. Wackes overlie the black shales to the south. All these rock types have been cut by late Precambrian diabasic intrusions, principally sills or near-conformable dykes. One sill is the norm for the property, always as the topmost layer up to 20-30 m thick capping the hills. Only diabase and shale are exposed on the property. Iron formation has been intersected at depth on the property. Greenstone was reported from deep drilling on the property (AFRI 52A05SE0038).

Mineralization

Mineralization Comments

Jan 29, 2018 (Therese Pettigrew) - Near-vertical faults. The faults have been filled by veins containing quartz (glassy, white, amethystine), calcite (clear, white) with lesser fluorite (green, purple) and occasionally barite (white, translucent). Barite is generally considered to represent a post-silver mineralizing event. Fault gouge is present in a number of the veins. Vugs lined with crystals are not uncommon. Cockade texture and mineral banding inward from the vein walls are also common. The veins are generally brecciated zones containing assorted angular fragments of the black shale or diabase. Often, solid veins up to 0.5 m wide are present within the breccia. Silicification is often measured in millimetres, however in some zones, silicification over widths of several metres is present associated with quartz stringer zones. Metallic minerals present in the veins include pyrite, marcasite, sphalerite, galena and occasionally chalcopyrite. The silver is present as films, leaves or nuggets in the form of the silver sulphide, acanthite (locally termed argentite) or less commonly as wire or dendritic native silver. The mineral assemblage is typical of low temperature and pressure deposition. Cobalt, nickel, arsenic and antimony minerals are rarely present. Silver values tend to occur very erratically within the veins and occasionally into fractures in the wallrock. The more significant silver values tend to be found where the veins are enclosed within the black shale and within 30 to 60 m of the overlying diabase. Generally, the veins where enclosed by diabase or iron formation did not carry silver. This observation has been explained as due to the precipitating action of the graphite present in the host shales. The diabase and iron formation, being free of graphite, were not suitable deposition sites for the silver. Silver is the only mineral to have been significantly profitably produced from the veins. Regionally, coarse calcite was mined for pebble dash for stucco in the 1920s and decorative stone (amethyst, etc.) have been collected from time to time. Testing has been carried out on some properties in the area to also recover zinc and fluorite. Some of these tests were promising, but the grades for zinc and/or fluorite appear to be too low for "ore" unless as by-products from a silver milling operation (AFRI 52A05SE0038). The main vein was about 274 m long, 1.2 m wide, and 122 m in depth. In the upper part of the mine, the grade was about 200 opt Ag (Sergiades, 1968). Grab sample 1099061 collected by Honey Badger Exploration in 2018 returned 0.9 g/t Ag, 1.23% Pb, and 0.94% Zn. DDH BM-18-002 returned up to 65 g/t Ag over 2.2 m and 0.92% Cu over 1.5 m. BM-18-004 returned up to 292 g/t Ag over 4.43 m including 921 g/t Ag over 1.4 m, as well as 0.96% Zn over 1 m. BM-18-006 returned up to 682 g/t Ag over 2.4 m including 1254 g/t Ag over 0.28 m. Cobalt mineralization was discovered in the Rove shale, with DDH BM-18-002 returning up to 0.2% Co over 1.5 m and 0.83% Co over 1.7 m. DDH BM-18-003 returned up to 0.36% Co over 3.1 m. Cobalt mineralization was also discovered at the contact between the diabase and shale, with DDH BM-18-004 returning up to 0.52% Co over 1.5 m and 0.5% Co over 2.9 m, and DDH BM-18-006 returning up to 0.53% Co over 2.6 m (Assessment report 20000017904).

Mineral Record Details

References

Book - Fort William and Port Arthur, and Thunder Cape Map-area, Thunder Bay District, Ontario; Geological Survey of Canada, Memoir 167

Publication Number: GSC Memoir 167 Page: 129-131  Date: 1931

Author: Tanton, T.L.

Publisher Name: Geological Survey of Canada

Location: https://doi.org/10.4095/100799

Mono - Silver cobalt calcite vein deposits of Ontario

Publication Number: MDC010 Page: 71  Date: 1968

Author: Sergiades A.O.

Publisher Name: Ontario Dept. of Mines

Location:

File - Hazard files, Thunder Bay Mineral department

Publication Number: Date: 1996

Author:

Publisher Name:

Location: Thunder Bay RGP

Part - Silver in Thunder Bay District

Publication Number: ARV20-01.004 Date: 1998

Author: Bowen N.L.

Publisher Name: Ontario Bureau of Mines

Location:

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