Ontario Geological Survey
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MDI42E12NW00046
| Record Name(s) | Brookbank Prospect - 1934, Metalore Property - 1981 |
|---|---|
| Related Record Type | Partial |
| Related Record(s) | |
| Record Status | Developed Prospect With Reported Reserves or Resources |
| Date Created | 1983-Mar-17 |
| Date Last Modified | 2022-Sep-27 |
| Created By | |
| Revised By |
Primary Commodities: Gold
Township or Area: Irwin
Latitude: 49° 42' 51.96" Longitude: -87° 50' 3.8"
UTM Zone: 16 Easting: 439848.61 Northing: 5507214.81 UTM Datum: NAD83
Resident Geologist District: Thunder Bay North
NTS Grid: 42E12NW
Point Location Description: Diamond-drill holes and stripped zone.
Location Method: Data Compilation
Access Description: The property is located in central Irwin Township, north of Windigokan Lake. The claims can be reached by travelling the Trans Canada Highway 11 for approximately 14 km east of Beardmore, north on Windigokan Lake Road for about 6.5 km and west by bush road for about 2.4 km.
1934: Claims covering the occurrence were staked by several individuals. Connell Mining and Exploration Co. Ltd. acquired the claims and conducted trenching, pitting and diamond-drilling. 1935: Exploration suspended due to low and erratic gold values. 1944: Noranda acquired the claims. A geological survey was conducted, and 6,091.3 feet of diamond-drilling done in 40 DDH. 1948: Claims were transferred to Dorion Red Lake Mines Limited. 1950: Claims were patented and acquired by Brookbank-Sturgeon Mines Ltd. Company listed as idle from 1951-1974. 1974-5: Lynx Canada Expl. Ltd. optioned the property and conducted prospecting, stripping, linecutting, magnetometer and geological surveys, and drilled 6 DDH totalling 376 m. 1981: Property was optioned by Metalore Resources Ltd. who conducted mag, VLF-EM and magniphase EM surveys. A 30 hole, 3567 m diamond-drill program followed. 1982-83: A grid was cut and a mag survey conducted. Three holes totalling 783 were drilled. 1984: Metalore Res. drilled approx. 23 in 23 DDH over the main Brookbank zone. 1986: Metalore drilled 70 shallow holes. Hudson Bay Gold Inc. optioned property. Ontex Resources filed a lawsuit against Metalore. 1987: Hudson Bay drilled 44 DDH totalling 11,203 m. 1988: Hudson Bay dropped option. Work by Metalore uncovered western Knox Lk.-Cherbourg zone. 1989: Placer Dome Inc. optioned the Brookbank property (incl. Cherbourg and Foxear zones) - conducted stripping, trenching and drilled 18 DDH totalling 7010 m. 1990: Ontex awarded controlling rights to the property and Metalore appeals the ruling. 1992: Placer Dome option fails due to unresolved controlling ownership. 1993: Metalore Res. regains property by appeal and drilled 4 DDH totalling 533 m. 1998: Fortune Minerals enters into agreement with Ontex, Metalore, and Faymar Gold. 2000: Ontex Res. Ltd. carried out an airborne geophysics and DD program. 2010: a preliminary economic assessment initiated by Micon International Liminted in June for Goldstone Resources Inc. 2011: Goldstone Resources taken over by Premier Gold Mines Limited. 2012: Premier Gold Mines drilled 2 DDH totalling 1359 m.
| Office File Number | Online Assessment File Identifier | Online Assessment File Directory |
|---|---|---|
| 2.20998 | 42E11NW2003 | 42E11NW2003 |
| 2.10902 | 42E12NE0100 | 42E12NE0100 |
| 2.20298 | 42E12NW2012 | 42E12NW2012 |
| 17 | 42E12NW0092 | 42E12NW0092 |
| 63.3253 | 42E12NW0097 | 42E12NW0097 |
| 63.4757 | 42E12NW0043 | 42E12NW0043 |
| 63.5091 | 42E12NW0024 | 42E12NW0024 |
| 63.3353 | 42E12NW0090 | 42E12NW0090 |
| 2.20825 | 42E12NW2015 | 42E12NW2015 |
| 63.4167 | 42E12NW0074 | 42E12NW0074 |
| 63.4852 | 42E12NW0080 | 42E12NW0080 |
Province: Superior
Subprovince: Wabigoon
Belt: Beardmore-Geraldton
Geological Age: Archean
Dec 07, 2005 (G White) - The Brookbank Prospect is located within the southern portion of the Paint Lake fault zone at the northwestern boundary of the main east-trending Beardmore-Geraldton metasedimentary-metavolcanic belt. This regional east- trending fault structure separates older felsic-rich metavolcanic rocks of the north-trending Onaman-Tashota belt from the main belt. A deposit of 1.4 million tons at a grade of 0.263 has been established on the Brookbank property, primarily from Placer Dome Inc.'s work in 1990. Two additional gold-bearing zones are known, namely the Cherbourg and Foxear zones, located west and east of the main horizon and have been the focus of much of the present drilling by Ontex Resources Ltd. (2000). All three gold-bearing horizons are proximal to the Brookbank fault, which is a southern splay of the Paint Lake Fault zone.
Dec 07, 2005 (B Nelson) - The property is underlain by Early Precambrian mafic metavolcanics, diorite, iron formation, arkose, slate, mudstone, greywacke and conglomerate. The mafic metavolcanics are in fault contact with the metasediments to the north. There is considerable lithological variation over short distances. The Brookbank Prospect is situated on a splay of the Paint Lake Fault, a major regional transcurrent fault. The diorite unit is fault controlled similar toe the diorite-gabbro intrusions within the Bankfield-Tombill Fault at Geraldton. Foliation of the rocks is generally northeasterly and steeply dipping to the south. The Brookbank Zone to the west is predominantly hosted in sedimentary rocks. To the east the zone trends into the volcanic rocks. The mineralized zone consists of a pyritized and silicified carbonate unit that extends some 610 m along the contact between mafic metavolcanic and overlying metasedimentary rocks. Gold mineralization is associtated with fine disseminated euhedral to subhedral pyrite grains. Pyrite comprises from 2 to 10% of the rock. Visible gold is quite rare. Gold and chalcopyrite particles of extremely small size occur in fractures in pyrite, and sometimes appear completely enclosed in pyrite grains or in gangue. At depth the Brookbank Zone is a well brecciated fault zone as opposed to the pod-like structure noted on the surface. Even at depth, 'high density drilling across the eastern half of the zone has indicated rather narrow (Less than 5 m) intermittent sections carrying economic values in gold.
Dec 07, 2005 (Q Unknown) - In some places the greywacke grades directly into arkose, and in others, a fine, dense mudstone phase intervenes over a distance of several feet in the direction of stratigraphic sequence. The greywacke, in the vicinity of the main ore zone, gets progressively coarser going north (across the bedding) and hence there is a gradual change into coarser material, until the conglomerate, which contains well rounded pebbles, begins to appear frequently only in the northern reaches of the coarser greywacke. The Brookbank prospect is situated on a splay of the Paint Lake Fault, a major regional transcurrent fault. The diorite unit is fault controlled, similar to the diorite-gabbro intrusions within the Bankfield-Tombill Fault at Geraldton. Foliation of the rocks is generally northeasterly and steeply dipping to the south.
| Rock Type | Rank | Composition | Texture | Relationship | Intermediate lava flow-unsubdivided | 1 | Andesite | Near |
|---|---|---|---|---|
| Diorite | 2 | Diorite | Near | |
| Sandstone | 3 | Arkose | Near | |
| Sandstone | 4 | Greywacke | Near | |
| Mafic Schist | 5 | Greenstone | Schistose | Host |
| Intermediate lava flow-unsubdivided | 6 | Andesite | Near | |
| Diorite | 7 | Diorite | Near | |
| Conglomerate | 8 | Near | ||
| Vein | 9 | Quartz-Carbonate | Host |
Dec 07, 2005 (B Nelson) - The andesites are fine-grained, dark greenish and often schistose. Occasional narrow tuff horizons are interbedded with flows and such horizons have suffered the most intense shearing. The diorite is a medium-grained dark greenish rock which weathers to a a rough surface with white and light colors predominant. The arkose is medium grained, buff to cream colored and usually quite schistose. Highly schistose sericitic phases are quite common along the north margin of the ore zone.
Dec 07, 2005 (Q Unknown) - The andesites are fine-grained, dark greenish and often schistose. Amygdules and ellipsoidal structures were rarely observed. Occasional narrow tuff horizons are interbedded with flows and such horizons have suffered the most intense shearing. The diorite is a medium-grained dark greenish rock which weathers to a rough surface, with white and light grey colours predominant. An ophitic texture is sometimes easily seen in the hand specimen. The arkose is medium-grained, buff to cream coloured, and usually quite schistose. Highly schistose sericitic phases are quite common along the north margin of the ore zone. The presence of a few angular grains of red jasper is a very characteristic feature. Conglomerate is characterized by an abundance of water worn pebbles in a rather fine-grained chloritic matrix. The pebbles vary in size from very small up to several inches in diameter. A pinkish granite is the most common kind of pebble. Jasper and chert pebbles tend toward sub-angular outlines and are evenly distributed, but not abundant.
| Rank | Mineral Name | Class | Economic Mineral Type | Alteration Mineral Type | Alteration Ranking | Alteration Intensity | Alteration Style |
|---|---|---|---|---|---|---|---|
| 1 | Gold | Economic | Ore | ||||
| 2 | Chalcopyrite | Economic | Ore | ||||
| 3 | Molybdenite | Economic | Ore | ||||
| 4 | Pyrite | Economic | Ore | ||||
| 5 | Specularite | Economic | Ore | ||||
| Carbonate | Alteration | Carbonatization | 1 | Unknown | Replacement | ||
| Epidote | Alteration | Epidotization | 2 | Unknown | Replacement |
Dec 07, 2005 (B Nelson) - The sheared, altered and mineralized contact zone has been tested for a strike length of 762 m. A few significant intersections follow: In 1944 Noranda, in hole #21, intersected 1.95 m of 0.634 oz/ton Au. Hole #35 intersected 1.25 m of 1.12 oz/ton Au. In 1974 Lynx Canada, in hole BB-4, intersected 0.24 m of 1.59 oz/ton Au. Several holes intersected 1 m+ intersections of 0.14 oz/ton Au. Metalore intersected values as high as 0.50 oz/ton Au.
Dec 07, 2005 (Q Unknown) - The mineralized zone consists of a pyritized and silicified carbonate unit that extends some 600m along the contact between mafic metavolcanics and overlying metasediments. The average width of the zone is 30m. This zone is considered to be a replacement of alteration of the metavolcanics. Drilling, in places, suggests a sharp contact between the mafic metavolcanics and the polymictic conglomerate to the north. Gold mineralization is associated with fine disseminated euhedral to subhedral pyrite grains. Pyrite comprises 2 to 10% of the rock. At depth, the Brookbank Zone is a well brecciated fault zone, as opposed to the pod-like structure noted on surface.
Dec 07, 2005 (B Nelson) - The alteration zone has been described as follows: The usual sequence of material in the main ore zone from south to north is as follows. First, there is a well fractured greenstone contining occasional small stringers of hard, reddish, siliceous material, with slight pyritization. The rock changes northward into a highly brecciated dark brown to buff material. Qtz and qtz-carb veinlets are commonly seen. Fine grained pyrite is liberally distributed throughout the zone, but concentrated usually only in the more siliceous phases. When the north margin of the zone is approached, the first evidence of a chane is the appearance of a narrow band of dense black cherty material. Following this northward is a highly schistose, sericitic phase which grades into a schistified arkose. The arkose within variable distances usually changes into a fine-grained dark slaty (mudstone) phase, and thence into greywacke. Specularite, cp, and mo are present in the alteration zone, the lattter two being rare.
Dec 07, 2005 (Q Unknown) - Radioactive reddish potasium alteration is present.
Date: Dec 19, 1996
Geologist: B Nelson
Notes: The Beardmore-Geraldton Economic Geologist visited this occurence September 22, 1981, July of 1982, December 14, 1982, September 22, 1983, October 12, 1983, August 7, 1984 and July 18, 1985.
| Zone | Year | Category | Tonnes | Reference | Comments | Commodities |
|---|---|---|---|---|---|---|
| Brookbank Open Pit | 2021 | Inferred Mineral Resource | 45000 | Premier Gold NI 43-101 report, January 26, 2021 | 0.045 Mt @ 2.07 g/t Au (3,000 oz Au) | Gold 2.07 Grams per Tonne |
| Brookbank Underground | 2021 | Inferred Mineral Resource | 706000 | Premier Gold NI 43-101 report, January 26, 2021 | 0.706 Mt @ 3.38 g/t Au (77,000 oz Au) | Gold 3.38 Grams per Tonne |
| Brookbank Open Pit | 2021 | Indicated Mineral Resource | 1147000 | Premier Gold NI 43-101 report, January 26, 2021 | 1.147 Mt @ 2.24 g/t Au (83,000 oz) | Gold 2.24 Grams per Tonne |
| Brookbank Underground | 2021 | Indicated Mineral Resource | 2281000 | Premier Gold NI 43-101 report, January 26, 2021 | 2.281 Mt @ 7.06 g/t Au (517,000 oz Au) | Gold 7.06 Grams per Tonne |
| Brookbank Underground | 2012 | Inferred Mineral Resource | 403000 | NI 43-101 report, March 13, 2014 | Inferred: 0.403Mt @ 4.02 g/t Au (53000 oz Au) | |
| Brookbank Underground | 2012 | Measured + Indicated Resource | 1851000 | NI 43-101 report, March 13, 2014 | Measured and Indicated: 1.851 Mt @ 7.21 g/t Au (429000 oz Au) | |
| Brookbank Open Pit | 2012 | Measured + Indicated Resource | 2638000 | NI 43-101 report, March 13, 2014 | Open Pit: Measured and indicated: 2.638 Mt @ 2.02 g/t Au (171000 oz) | |
| Brookbank Open Pit | 2012 | Inferred Mineral Resource | 171000 | NI 43-101 report, March 13, 2014 | Inferred: 0.171 Mt @ 2.38 g/t Au (13000 oz Au) | |
| Brookbank | 2009 | Indicated Mineral Resource | 1217400 | NI 43-101 report, March 13, 2014, p. 6-18 | 1,217,400 @ 8.8 gpt Au for 345,600 oz Au | |
| Brookbank | 2009 | Inferred Mineral Resource | 813100 | NI 43-101 report, March 13, 2014, p. 6-18 | 813,100 @ 7.4 gpt Au for 192,800 oz Au |
Map - Sturgeon River gold area, District of Thunder Bay, Ontario
Publication Number: ARM45A Scale: 1:63,360 Date: 1998
Author: Bruce E.L., Laird H.C.
Publisher Name: Ontario Dept. of Mines
Location:
Book - Northern Miner historical file
Publication Number: N.Miner Date: 1996
Author:
Publisher Name:
Location: Thunder Bay RGP Assessment Files
Map - Irwin Township, District of Thunder Bay
Publication Number: P0481 Scale: 1:15,840 Date: 1997
Author: Mackasey W.O.
Publisher Name: Ontario Dept. of Mines
Location:
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:
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:
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:
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:
Book - GDIF 42E12NW (unpublished)
Publication Number: GDIF Date: 1988
Author: Ontario Geological Survey
Publisher Name: Ontario Geological Survey
Location: Thunder Bay RGP
File - Resident Geologist Mineral Deposit File
Publication Number: Min Dep Date: 1996
Author:
Publisher Name:
Location: Thunder Bay RGP
Thesis - Geology of the Brookbank Gold Deposit
Publication Number: MSc Thesis Date: 1946
Author: Colcleugh, V.D.
Publisher Name: University of Manitoba
Location: Thunder Bay RGP Office
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:
Part - The western part of the Sturgeon River area (Sturgeon R.-Beardmore section)
Publication Number: ARV45-02.002 Page: 60-117 Date: 1998
Author: Laird H.C.
Publisher Name: Ontario Dept. of Mines
Location:
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:
Book - Proceedings of the Geological Association of Canada, Vol 21
Publication Number: GACP 21 Page: 33-42 Date: 1970
Author: Ridler, R.H.
Publisher Name: Geological Association of Canada
Location: Thunder Bay RGP Library
Publication - Trans-Canada Property, Hardrock and Brookbank Projects Preliminary Economic Assessment, NI 43-101 Technical Report
Publication Number: 2014 NI 43-101 Date: 2014
Author: Stantec Mining
Publisher Name: Stantec for Premier Gold Mines
Location: SEDAR
Map - Precambrian Geology of the Paint Lake Fault Area, Beardmore Area, Northwestern Ontario
Publication Number: P3515 Scale: 1:10,000 Date: 2002
Author: DeWolfe J.C.
Publisher Name: Ontario Geological Survey
Location:
Map - Compilation series, Lake Nipigon sheet, District of Thunder Bay
Publication Number: P0257 Scale: 1:126,720 Date: 1984
Author: Stott G.M., McConnell C.D., Mason J.K.
Publisher Name: Ontario Geological Survey
Location:
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