Ontario Mineral Inventory

Ontario Geological Survey
Permanent Link to this Record: MDI42E11NE00003

Record: MDI42E11NE00003

General

Commodities

Primary Commodities: Gold

Secondary Commodities: Silver

Location

Township or Area: Errington

Latitude: 49° 41' 45.22"    Longitude: -87° 3' 12.38"

UTM Zone: 16    Easting: 496146.15   Northing: 5504821.16    UTM Datum: NAD83

Resident Geologist District: Thunder Bay North

NTS Grid: 42E11NE

Point Location Description: Minesite

Location Method: Data Compilation

Access Description: The property is located in southwestern Errington Township. The claim block is located 8.0 to 9.7 km west of Geraldton and is easily accessible by Trans Canada Highway 11 which passes through the south part of the property.

Exploration History

1931: Claims staked. 1932: 30 days assessment work filed on the two claims. 1934-35: Wells Longlac Gold Mines Ltd. conducted diamond-drilling (7510.6 m). Magnet Lake Gold Mines Ltd. conducted trenching. 1936: Magnet Consolidated Mines Ltd formed from the merger of Magnet Lake Gold Mines and Wells Longlac Mines Ltd. 1937: 3 compartment vertical shaft sunk to 115.8 m. Levels est. 44.2 m of cross-cutting was completed, but operations had to be suspended in May due to lack of finances. In October, Northern Empire Mines Ltd. received a 2 year option agreement. Patents were approved. 1938: Shaft deepened to 213.4 m with new levels established at 146.3 and 192.9 m. Underground development continued on all levels. Ore was milled at the neighbouring Tombill facility. 1939: Shaft was deepened and a new level established at 237.7 m. Underground dev't con't. A total of 12 DDH were drilled totalling 507.5 m. A 100 ton/d mill was built. 1940-42: Shaft was deepened to 339.9 m with new levels established at 283.5 and 329.3 m. Underground dev't con't;. A cyanide plant was added to the mill and began operations in July. 1941: Shaft was deepened to 540.1 m and new levels were established at 374.9, 420.6, 474, and 527.3 m. 14 DDH were drilled from underground totalling 338.3 m 1942: Mining and milling continued with underground development only on the lower levels. 51 DDH totalling 1279.6 m were drilled underground. 1943: Mining and milling continued for most of the year, with underground development on the lower levels only. 39 DDH totalling 1860.2 m were drilled from underground. Operations suspended in Oct. due to limited ore reserves. 1945: Workings dewatered and limited drifting and cross-cutting were performed. 2 DDH totalling 183.5 m were drilled from underground. 1946: Underground dev't con't with a winze being driven from the 9th to 11th levels; 36 holes totalling 2939.8 m drilled underground; milling resumed in March. 1947: Winze was deepened to 581.3 m with a new level established at 574.2 m. 7 DDH totalling 1228 m were drilled from underground. 1948: Mining and milling continued. Winze was deepened to 636.1 m with a 13th level established at 620.9 m. 1949: Mining and milling continued. Winze was deepened to 673.6 m with a level established at 658.4 m. 14 DDH totalling 540.7 m were drilled from underground. 1950: Mining and milling continued. 46 DDH totalling 2548.1 m were drilled from underground. 1951: Mill shut down in July. Underground dev't con't though, with the winze deepened to 804.7 m and new levels established at 704.7, 749.8 and 795.5 m. 14 DDH totalling 889.4 m were drilled from underground. 1952: Underground work consisted of salvage only. 3 DDH totalling 525.9 m were drilled from underground. 7 DDH totalling 1288 m were drilled from surface. 1965: Company focussed on finding new orebodies. Plant dismantled. 1979: Magnet Consolidated's properties were expropriated for failure to pay taxes, then released for staking. 1979-81: Roxmark Mines Ltd. acquired most of the old ground. 1981: A grid was cut; mag, VLF and geochemical surveys conducted. 1982: More mag and VLF done. Dewatering commenced. 1983: Dewatering con't, along with surface exploration. 1984: Dewatering and drilling con't. Operations later suspended due to lack of funds. Water level held at the 11th level. 2007: Premier Gold Mines optioned the property from Roxmark in September and conducted a drill program. 2008: Premier continued their drill program. 2009-10: The Magnet mine site was inspected by the Ministry of Northern Development, Mines and Forestry. Phase 1 of the rehabilitation has been completed.

Assessment Work on File

Geology

Province: Superior

Subprovince: Wabigoon

Belt: Beardmore-Geraldton

Geological Age: Archean  

Geology Comments

Dec 07, 2005 (B Nelson) - Only in one locality on the property does bed rock outcrop at the surface. Correlation of geological structures depended solely upon the information secured from diamond-drill holes and underground workings. For the most part, the property is underlain by clastic sediments, including conglomerate, iron formation, greywacke and slate. These have been intruded in turn by diorite, diorite porphyry, albite porphyry and diabase. Several bands of iron formation, up to 13.7 m in width, cross the property. The most abundant of the sedimentary rocks are fine-grained, dark to greenish grey, well-bedded greywackes. Intrusive into the sediments in the vicinity of the mine are many dykes and sill-like masses of diorite. The youngest rock in the mine area is massive quartz diabase. In the underground workings, several important, and numerous minor, post-ore faults cut and offset the ore zones. The orebodies are shoots within quartz veins. There have been five zones opened up, but only 2 have proved productive. The orebodies consists chiefly of quartz with small amounts of carbonate and subordinate sulphides. For the most part, the sulphides are confined to narrow selvages and books of altered wall rock along or within the individual veins, although amall amounts of these minerals are frequently found completely enclosed by the vein quartz itself. The mineralization at the Magnet Mine apparently took place in three stages, separated by periods of fracturing and in the last instance by faulting as well. The Magnet Zone and the North Zone are structurally associated with iron formation. Shearing is accentuated where the zones encountered iron formation.

Lithology

Lithology Comments

Dec 07, 2005 (B Nelson) - The most abundant of the sedimentary rocks are fine-grained, dark to greenish-grey, well-bedded greywackes. In the underground workings, they are highly sheared or fractured, and any original structures, such as bedding, cross lamination, or grain gradation, have been obliterated. South of the Magnet Vein zone, there are three varieties that differ from normal greywackes of the sedimentary series. They are known as 'sericitic quartzite', 'black slate', and 'semi-slate'. The black slate is separated from the typical greywackes to the north by a band of dark green semi-slate. Like the black slate, this rock consists essentially of fine-grained quartz, chlorite, and sericite arranged in parallel foils. The sericitic quartzite is a light grey to buff-colored rock, coarser-grained than the typical greywacke. The diorite in the underground workings is a dark green, highly sheared and contorted rock often indistinguishable from the greywackes which enclose it.

Mineralization

Mineralization Comments

Dec 07, 2005 (B Nelson) - Four non-metallics have been recognized, these being quartz, tourmaline, and two varieties of carbonate (dolomitic ankerite and dolomite). Roxmark Mines Ltd. DDH U-2-31 indicates the presence of minor fuchsite in altered veinlet margins. With more shearing and possibly a chemical reaction with the iron formation, there is a markedly higher zone of pyrite and pyrrhotite mineralization in the vein zones when they are in iron formation than when they are in greywacke. On the other hand, gold values tend to decrease after the vein system has cut through the iron formation. During mill clean-up, 82 oz Au and 9 oz Ag were produced.

Nov 27, 2018 (Therese Pettigrew) - The geology of the mine consists of metasediments, mostly greywacke with interbeds of iron formation and conglomerate, striking N290° and dipping 75 to 80°. Intrusive rocks consist of dykes and sill-like masses of diorite and porphyry and younger diabase dykes cutting across the formations. The two deposits, raking N300 to N315°, consist of lenticular quartz veins and accompanying veinlets predominantly in sheared greywacke. The Magnet vein zone, with an average strike of N285° and a near-vertical dip, was developed over a maximum length of about 1,300 ft (396.2m). The leaner North zone, 50 to 100 ft (15.2 to 30.5 m) to the north, strikes N280° and dips vertically. The deposits at the Magnet mine consist chiefly of quartz with small amounts of carbonate and subordinate sulfides. The metallic constituents, which seldom constitute more than 5% of the mineralization, are arsenopyrite, pyrite, pyrrhotite, chalcopyrite, sphalerite, galena and gold (Gignac et al., 2016). Premier’s 2008 drill program intersected a number of high-grade zones, including 67.08 gpt Au over 2 m in the Highway Zone and 10.22 gpt Au over 2.5 m and 8.14 gpt Au over 2 m in the Benedict Zone. Significant results from drilling on the Highway Zone include the following assays: PM-07-002: 6.28 gpt Au over 2 m (496-498 m), 8.84 gpt Au over 1 m (736-737 m), 9.86 gpt Au over 1 m (907-908 m) PM-07-009: 7.83 gpt Au over 1 m (752-753 m) PM-07-017: 12.67 gpt Au over 0.5 m (247.5-248 m) PM-08-014: 10.06 gpt over 1 m (249-250 m), 7.30 gpt Au over 4.5 m (292.5-297 m) including 26.78 gpt Au over 1 m (293-294 m) PM-08-018: 67.08 gpt Au over 2 m (129-131 m) including 125.44 gpt Au over 1 m (129-130 m)

Alteration Comments

Dec 07, 2005 (B Nelson) - The Bankfield-Tombill fault zone crosses the Magnet property at a point 350 m south of the main shaft. As elsewhere, it is a highly silicified and carbonatized zone, varying in width from 15 m to 30 m. The most significant minor post-ore fault encountered underground is the Magnet Fault which is a highly silicified breccia zone. Each of 4 other post-ore faults is marked by a zone of black, lustrous, anisotropic material. In many places the zones are fractured and the fractures filled with milky white quartz and calcite.

Mineral Record Details

Site Visit Information

Date: Jan 10, 1997

Geologist: B Nelson

Notes: The Beardmore-Geraldton Economic Geologist visited the Magnet Mine site in June 1982, July 22, 1981, September 1981, November 1981, July 14, 1982, July 7, 1983, July 19, 1983, September 20, 1983, October 24-25, 1983, December 9-10, 1983, and June 12, 1984.

References

Map - Little Long Lac gold area, District of Thunder Bay, Ontario

Publication Number: ARM44D Scale: 1:31,680    Date: 1997

Author: Bruce E.L.

Publisher Name: Ontario Dept. of Mines

Location:

Part - Geology of Errington Township, Little Long Lac area

Publication Number: ARV60-06 Date: 1997

Author: Pye E.G.

Publisher Name: Ontario Dept. of Mines

Location:

Publication - NI 43-101 Technical Report, Hardrock Project, Ontario, Canada

Publication Number: 2016 NI 43-101 Date: 2016

Author: Gignac, L.-P., Schlyter, G., Menard, M., Sirois, R., Murahwi, C.

Publisher Name: G Mining Services for Premier Gold

Location: SEDAR

Thesis - Geology of the Magnet Consolidated Gold Mine

Publication Number: MSc Thesis Date: 1950

Author: Nelson, R.C.

Publisher Name: University of Toronto

Location: Thunder Bay RGP

Map - Compilation series, Geraldton sheet, Thunder Bay and Cochrane districts

Publication Number: P0241 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 Date: 1986

Author: Mason J.K., White G.D.

Publisher Name: Ontario Geological Survey

Location:

Part - Little Long Lac gold area

Publication Number: ARV44-03 Date: 1997

Author: Bruce E.L.

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 - Mineral deposits series, Ontario mineral potential, Longlac sheet, districts of Thunder Bay and Cochrane

Publication Number: P1527 Scale: 1:250,000    Date: 1978

Author: Springer J.S.

Publisher Name: Ontario Geological Survey

Location:

Map - Township of Errington, District of Thunder Bay, Ontario

Publication Number: M1951-07 Scale: 1:12,000    Date: 1997

Author: Horwood H.C., Pye E.G.

Publisher Name: Ontario Dept. of Mines

Location:

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

Publication Number: MDC013 Date: 1971

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

Publisher Name: Ontario Dept. of Mines and Northern Affairs

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:

Part - Mining operations in 1952

Publication Number: ARV62-02 Page: 55  Date: 1997

Author: Field D.J.

Publisher Name: Ontario Dept. of Mines

Location:

Map - Thunder Bay data series, Lindsley Township area, Thunder Bay District

Publication Number: P2519 Scale: 1:15,840    Date: 1982

Author: Love W.D.

Publisher Name: Ontario Geological Survey

Location:

Part - Mines of Ontario in 1950

Publication Number: ARV60-02 Page: 52  Date: 1997

Author: Reade M.

Publisher Name: Ontario Dept. of Mines

Location:

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