Ontario Geological Survey
Permanent Link to this Record:
MDI42D13SW00005
| Record Name(s) | Finch Head - 1840, Addicks Canadian - 1974, Mentor Addicks - 1974, Horlac Mines Ltd - 1954, Moffat's Strait - 1954 |
|---|---|
| Related Record Type | Simple |
| Related Record(s) | |
| Record Status | Occurrence |
| Date Created | 1980-Jan-21 |
| Date Last Modified | 2022-May-09 |
| Created By | |
| Revised By |
Primary Commodities: Copper
Secondary Commodities: Silver
Township or Area: St. Ignace Island Area
Latitude: 48° 49' 53.92" Longitude: -87° 45' 13.58"
UTM Zone: 16 Easting: 444681.86 Northing: 5409014.68 UTM Datum: NAD83
Resident Geologist District: Thunder Bay South
NTS Grid: 42D13SE, 42D13SW
Point Location Description: Diamond drill holes
Location Method: Conversion from MDI
Access Description: The occurrence is located at the north end of Moffat Strait between St. Ignace and Simpson Islands (claim maps G-54 and G-610). Access is by water from Nipigon or via aircraft to the north end of Moffat Strait. A boat launch is also available from Nipigon Bay Resort.
1840: Showing was first discovered. Mid-1800s: sinking of 2 shallow shafts with limited drifting. 1954-55: Surface work was completed on the occurrence by Horlak Mines Limited and 8 diamond drill holes totalling 155 m were drilled. 1964: Addicks Canadian Properties Incorporated carried out prospecting, trenching, sampling, and drilled 6 diamond drill holes totalling 469 m. 1970: Addicks Canadian Properties Inc. conducted magnetic and EM surveys. 1989: Prospecting and sampling were carried out by J. Ferguson and A. Ferguson.
| Office File Number | Online Assessment File Identifier | Online Assessment File Directory |
|---|---|---|
| 16 | 42D13SW8298 | 42D13SW8298 |
| 10 | 42D13SW8304 | 42D13SW8304 |
| 63.2868 | 42D13SW0001 | 42D13SW0001 |
Province: Southern
Supergroup: Keweenawan Supergroup
Geological Age: Paleoproterozoic
Dec 07, 2005 (B Nelson) - The occurrence is classed as a 'polymetallic vein, volcanic-hosted copper' deposit. Four mineralized zones, each consisting of vertical, chalcocite-bearing calcite stringers occur in flat-lying amygdaloidal lava, and strike east-west. Three of the zones occur west of Moffat Strait on the northeast shore of St. Ignace Island and the fourth on the northwest shore of Simpson Island. The showing at the north end of Moffat Strait, on St. Ignace Island, consists of mineralized veins that cut the Osler amygdaloidal basalts. In 1970, geophysical surveys were conducted over the claim group by Addicks Canadian Properties Incorporated. An electromagnetic survey indicated four weak conductive zones that were thought to be of topographic origin. No correlation with known copper-silver mineralization was established. A magnetometer survey outlined 6 easterly-trending anomalous zones, but these were thought to be the results of magnetite concentrations in the volcanic flows. In 1964, Addicks Canadian Properties Incorporated drilled 6 holes, over a strike length of 300 m, on the Moffat Strait property. The drill holes had a combined length of 462 m. All 6 holes intersected chalcocite in calcite veins. Trenching and drilling on the property in 1954-55, by Horlac Mines Limited, uncovered 4 mineralized veins. The largest is 1.8 m wide; the smallest 7 cm wide. The total width of the mineralized zone containing the veins was estimated at 20 m. Drilling offshore in 1955 traced the veins for 15 m along strike under Moffat Strait. Resident Geologist staff observed 3 veins across 3 to 4 m. These calcite veins were hosted in amygdaloidal and vesicular basalt of Keweenawan age. The veins strike 270 degrees and dip 70 degrees north. Several small trenches and a small open cut were observed 5 m in from the shoreline.
| Rock Type | Rank | Composition | Texture | Relationship | Mafic lava flow-unsubdivided | 1 | Osler Basalts | Amygdaloidal | Host |
|---|---|---|---|---|
| Vein | 2 | Calcite | Host |
| Rank | Mineral Name | Class | Economic Mineral Type | Alteration Mineral Type | Alteration Ranking | Alteration Intensity | Alteration Style |
|---|---|---|---|---|---|---|---|
| 1 | Chalcocite | Economic | Ore | ||||
| 2 | Silver | Economic | Ore | ||||
| 1 | Calcite | Economic | Gangue | ||||
| Calcite | Alteration | Hydrothermal | 1 | Unknown | Veins |
Dec 07, 2005 (B Nelson) - Mineralization consists of chalcocite with traces of silver in calcite veins and veinlets in amygdaloidal lava of the Osler Group volcanics. All six holes drilled by Addicks in 1964 intersected chalcocite in calcite veins. These veins averaged 0.1% copper across a width of 0.6 m. Trace amounts of silver were also found. The average grade reported by Horlac Mines Limited is 0.8% copper. Two analyses indicated that small amounts of silver are present. Samples taken by Resident Geologist personnel returned: 89-BSI-01: 0.0002 oz/ton Au; 1.19 oz/ton Ag; 4.5% Cu. 89-BSI-02: Nil Au; Trace Ag; 0.12% Cu.
Apr 29, 2019 (Therese Pettigrew) - Copper-silver mineralization is associated with an east-west-trending fracture zone in the NE portion of St. Ignace Island (Assessment report 42D13SW0001).
Date: Feb 06, 1997
Geologist: B Nelson
Notes: Resident Geologist staff visited the occurrence in July of 1989.
Map - Nipigon-Schreiber, geological compilation series, Thunder Bay District
Publication Number: M2232 Scale: 1:253,440 Date: 1973
Author: Carter M.W., McIlwaine W.H., Wisbey P.A.
Publisher Name: Ontario Division of Mines
Location:
Mono - Copper, nickel, lead and zinc deposits in Ontario (revised to February, 1957)
Publication Number: MDC002 Page: 50 Date: 1957
Author: Thomson J.E., Ferguson S.A., Johnston W.G.Q., Pye E.G., Savage W.S., Thomson R.
Publisher Name: Ontario Dept. of Mines
Location:
File - Resident Geologist Mineral Deposit Files
Publication Number: Min Dep Date:
Author:
Publisher Name:
Location: Thunder Bay RGP
Map - St. Ignace Island and adjacent islands, Thunder Bay District
Publication Number: M2285 Scale: 1:63,360 Date: 1974
Author: Giguere J.F.
Publisher Name: Ontario Division of Mines
Location:
Mono - Copper, nickel, lead and zinc deposits of Ontario
Publication Number: MDC012 Page: 325 Date: 1969
Author: Shklanka R.
Publisher Name: Ontario Dept. of Mines
Location:
MonoMap - Geology of St. Ignace Island and adjacent islands, District of Thunder Bay
Publication Number: R118 Page: 28 Date: 1975
Author: Giguere J.F.
Publisher Name: Ontario Division of Mines
Location:
Mono - Mineral Occurrences in the Nipigon-Marathon Area, Volumes 1 and 2.
Publication Number: OFR5951 Page: 104 Date: 1996
Author: Schnieders B.R., Smyk M.C., Speed A.A., McKay D.B.
Publisher Name: Ontario Geological Survey
Location:
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