Ontario Mineral Inventory

Ontario Geological Survey
Permanent Link to this Record: MDI52F03NW00004

Record: MDI52F03NW00004

General

Commodities

Primary Commodities: Gold

Secondary Commodities: Copper, Silver

Location

Township or Area: Bluffpoint Lake Area

Latitude: 49° 8' 7.38"    Longitude: -93° 21' 42.23"

UTM Zone: 15    Easting: 473614   Northing: 5442569    UTM Datum: NAD83

Resident Geologist District: Kenora

NTS Grid: 52F03NW

Point Location Description: Shaft Location on map P1243

Location Method: Conversion from MDI

Access Description: Opawica Explorations Inc. is currently exploring a property in the vicinity of Straw Lake (NTS 52F/03NW). The 15-claim property is located approximately 62 km north-northeast of Fort Frances, Ontario (Figure 11). The property can be accessed by the all-weather Cedar Narrows Road, which departs west from Highway 502. The Cedar Narrows Road transects the western portion of the property, whereas the eastern parts of the property may be accessed off the Floyd Lake Road, east of the Cedar Narrows Road. (OFR 6127, p. 26, 2004)

Exploration History

1933: M. Mosher and F. Grozelle discover gold in quartz veins on the south shore of the “north arm” of Straw Lake. W. Lucy discovered gold on the south side of the “south arm” of Straw Lake. 1934: Straw Lake Beach Mine Syndicate was formed to develop the Mosher Vein. 1934-41: mine was developed to a depth of 725 feet and equipped with a 60 tpd flotation/cyanidation mill. Mine closed in 1941 1945: Sylvanite Gold Mines drilled 6 DDH totalling 342 m. 1970: Freeport Canadian Exploration conducted an airborne geophysical survey, ground EM and magnetic surveys, and drilled 3 DDH. 1976: Minedel Mines conducted geological mapping, sampling and drilled 3 DDH totalling 890 m. 1983: Sparton Resources conducted line cutting, VLF-EM, magnetometer, and IP/resistivity surveys, soil and humus sampling, geological mapping and sampling, and drilled 5 DDH totaling 486 m. 1988: Dayton Porcupine Gold Mines Ltd. drilled 10 DDH totaling 1210 m. 1995: Tri Origin Exploration Ltd. conducted trenching, IP geophysical surveys, and drilled 7 DDH totalling 1772 m. 2000: R.J. Fairservice outlined gold-bearing alteration zones. 2003: Opawica Exploration Inc. optioned the property from R.J. Fairservice and conducted stripping, geological mapping, sampling, and drilled 12 DDH totalling 1775 m. 2007: Whetstone Minerals Ltd. drilled 10 DDH totalling 1990 m. 2011: Mineral Mountain Resources drilled 62 DDH totalling 8162 m (at least 8 DDH at Straw Lake Beach Mine). 2012: Mineral Mountain drilled 7 DDH totalling 2022 m.

Assessment Work on File

Geology

Province: Superior

Subprovince: Wabigoon

Terrane: Western Wabigoon

Belt: Eagle-Wabigoon-Manitou

Geological Age: Precambrian  

Geology Comments

Feb 19, 2010 (D Scholtz) - In early December 2003, Opawica continued their drill program, results from the next 6 drill holes yielded disappointing results and the Company announced that no further work would take place (Opawica Explorations Inc., press release, January 6, 2004). The Straw Lake property represents an unusual gold deposit model within the Kenora District. Observations made during a property visit in August led the author to counter the Company's interpretation of Edward.s lineaments as faults. Faulting in the host trondhjemite can be reinterpreted to represent conjugate fracture sets typical of cooling intrusive bodies. It has been interpreted that the development and transportation of hydrothermal fluids, including dissolved metallic minerals is controlled by these fractures and the lithology. The Lawrence lobe may represent a series of intrusive pulses, parts of which may represent a subvolcanic source to the overlying Yoke.Straw Lake volcanic rocks. The initial intrusive pulse involved Edward's Contact Zone trondhjemite-granodiorite (CZtg), and possibly the Bluffpoint quartz diorite. Interaction with the overlying Yoke. Straw Lake volcanic sequence produced the Contact Zone agmatite (Edwards and Davis 1984). A lengthy period of quiescence allowed the formation of a conjugate set of cooling fractures. The Chuck Lake pluton and/or the Lawrence Lake trondhjemite possibly represent a subsequent renewal of intrusive activity. This second phase of intrusion could have generated sufficient hydrothermal activity to allow for transport of gold and other metals through the fractured CZtg. The abundant fractures in the trondhjemite acted as a pathway for enhanced fluid flow, which allowed potentially mineralized hydrothermal fluids to alter the adjacent host rock and deposit gold. It has been noted that one of the major fractures appears to line up with the Straw Lake Beach Mine, a quartz vein system hosted by the overlying Yoke-Straw Lake volcanic rocks. It could be postulated that when the migrating hydrothermal fluids came into contact with the volcanic rocks, they “blew out” into the less competent units and formed the gold-bearing quartz veins, which host the Straw Lake Beach Mine. The Straw Lake Beach Mine is a viable exploration target, however, the potential for a large tonnage low-grade deposit within the intrusive rocks to the north is a significant and possibly more attractive target. Based on this reinterpretation, fracture systems may occur north of the current property further into the Bluffpoint quartz diorite and Chuck Lake stock. Fractures with attendant alteration haloes and mineralization, similar to that observed on the property, will be explored for during a reconnaissance road traverse planned for the summer of 2004. (OFR 6127, p. 26-28, 2004)

Lithology

Lithology Comments

Feb 19, 2010 (C Ravnaas) - GRADE: AVERAGE GRADE MILLED 0.34 OPT AU, SIZE: LENGHT OF 183 M AVERAGING 0.80 OPT AU OVER 0.34 M. Produced 11,568 oz Au and 1,049 oz Ag from 33,662 tons.Reserves are 32,000 tons at 0.20 opt Au probable.32,000 tons at 0.20 opt and 30,000 tons at 0.15 opt Au possible.48,000 tons at 0.20 opt Au speculative from OFR 5332 table 14 on page 47. The Straw Lake property is underlain by felsic intrusive rocks of the Lawrence Lake lobe of the Atikwa Batholith, within the western Wabigoon Subprovince. Mapping by Edwards (1983) differentiated the Lawrence Lake batholith into 3 phases, .. an early, marginal, subordinate amphibole diorite to gabbro phase at Sullivan Lake; a northern, intrusive diorite to quartz diorite phase between Bluffpoint and Harris lakes; and a later granodiorite to trondhjemite phase, south and southwest of Harris Lake.. The property is underlain by the latter 2 phases of diorite-quartz diorite and granodiorite-trondhjemite and a mixed contact zone between the batholith and supracrustal rocks. During his mapping project, Edwards (1983) noted a sample of altered trondhjemite, located north of Floyd Lake, which assayed 0.54 ounce gold per ton. Edwards (1983) commented: "Exploration for gold in both the endocontact and exocontact zones of this part of the Lawrence Lake Batholith is warranted." Following the release of the preliminary geology map in 1977 (Edwards and Sutcliffe 1977), prospector R. Fairservice staked the Edwards' gold occurrence. Initial prospecting yielded several other gold occurrences in the area west of Edwards' discovery assay. Fairservice was successful in optioning the property to several companies including Selco Mining Corp. (1980.82); Noranda Exploration Company (1982.84); Corporation Falconbridge Copper (1984.1987); and Minnova Inc. (1988.89). Work conducted by these companies included sampling; linecutting; geological mapping; induced polarization (IP), magnetometer and very long frequency electromagnetic (VLF-EM) geophysical surveys; humus geochemical sampling; stripping, trenching; and diamond drilling. After the Minnova option, the claims lapsed and the property sat dormant until 2000 when Fairservice started re-staking the core of the property. Additional prospecting by Fairservice identified additional gold occurrences, after which Opawica Exploration Inc. optioned the property in late 2002. Opawica's initial exploration program included an extensive stripping and trenching program covering the Pine Centre, Pine West, Pine East and Pine Hill gold zones, all located west of Edward's occurrence. A total of 32 areas were stripped and 273 samples collected. At the Pine Centre gold zone, 100 samples averaged 1.74 g/t Au, and of these, 74 samples averaged 2.73 g/t Au. Twenty-three samples were taken at the Pine East area, and analyses ranged from nil to 13.4 g/t Au. Stripping and sampling was conducted at the Pine Hill area on 6 separate zones, 4 of which returned values up to 1.32 g/t Au. The other 2 stripped zones returned values ranging from 0.52 to 3.76 g/t Au. At the Pine West area, 7 areas were stripped and 37 samples collected. Five samples from one of the stripped zones returned values ranging from 0.74 to 3.25 g/t Au (Opawica Explorations Inc., press release, July 7, 2003). In August 2003, Opawica initiated a twenty-hole Phase I diamond drill program. Holes OPW-2 and OPW-3 were drilled on the Pine Centre gold zone. The following results were reported: Hole OPW-2 intersected 15.7 m grading 1.00 g/t Au; Hole OPW-3 intersected 14.5 m grading 1.25 g/t Au. Hole OPW-6, targeting the Pine East zone, intersected 3.2 m grading 3.43 g/t Au and 0.8 m grading 6.39 g/t Au (Opawica Explorations Inc., press release, September 4, 2003) (OFR 6127, p. 26-28, 2004)

Mineralization

Mineralization Comments

Feb 19, 2010 (C Ravnaas) - GRADE: AVERAGE GRADE MILLED 0.34 OPT AU, SIZE: LENGHT OF 183 M AVERAGING 0.80 OPT AU OVER 0.34 M. Produced 11,568 oz Au and 1,049 oz Ag from 33,662 tons.Reserves are 32,000 tons at 0.20 opt Au probable.32,000 tons at 0.20 opt and 30,000 tons at 0.15 opt Au possible.48,000 tons at 0.20 opt Au speculative from OFR 5332 table 14 on page 47. The Straw Lake property is underlain by felsic intrusive rocks of the Lawrence Lake lobe of the Atikwa Batholith, within the western Wabigoon Subprovince. Mapping by Edwards (1983) differentiated the Lawrence Lake batholith into 3 phases, .. an early, marginal, subordinate amphibole diorite to gabbro phase at Sullivan Lake; a northern, intrusive diorite to quartz diorite phase between Bluffpoint and Harris lakes; and a later granodiorite to trondhjemite phase, south and southwest of Harris Lake.. The property is underlain by the latter 2 phases of diorite-quartz diorite and granodiorite-trondhjemite and a mixed contact zone between the batholith and supracrustal rocks. During his mapping project, Edwards (1983) noted a sample of altered trondhjemite, located north of Floyd Lake, which assayed 0.54 ounce gold per ton. Edwards (1983) commented: "Exploration for gold in both the endocontact and exocontact zones of this part of the Lawrence Lake Batholith is warranted." Following the release of the preliminary geology map in 1977 (Edwards and Sutcliffe 1977), prospector R. Fairservice staked the Edwards' gold occurrence. Initial prospecting yielded several other gold occurrences in the area west of Edwards' discovery assay. Fairservice was successful in optioning the property to several companies including Selco Mining Corp. (1980.82); Noranda Exploration Company (1982.84); Corporation Falconbridge Copper (1984.1987); and Minnova Inc. (1988.89). Work conducted by these companies included sampling; linecutting; geological mapping; induced polarization (IP), magnetometer and very long frequency electromagnetic (VLF-EM) geophysical surveys; humus geochemical sampling; stripping, trenching; and diamond drilling. After the Minnova option, the claims lapsed and the property sat dormant until 2000 when Fairservice started re-staking the core of the property. Additional prospecting by Fairservice identified additional gold occurrences, after which Opawica Exploration Inc. optioned the property in late 2002. Opawica's initial exploration program included an extensive stripping and trenching program covering the Pine Centre, Pine West, Pine East and Pine Hill gold zones, all located west of Edward's occurrence. A total of 32 areas were stripped and 273 samples collected. At the Pine Centre gold zone, 100 samples averaged 1.74 g/t Au, and of these, 74 samples averaged 2.73 g/t Au. Twenty-three samples were taken at the Pine East area, and analyses ranged from nil to 13.4 g/t Au. Stripping and sampling was conducted at the Pine Hill area on 6 separate zones, 4 of which returned values up to 1.32 g/t Au. The other 2 stripped zones returned values ranging from 0.52 to 3.76 g/t Au. At the Pine West area, 7 areas were stripped and 37 samples collected. Five samples from one of the stripped zones returned values ranging from 0.74 to 3.25 g/t Au (Opawica Explorations Inc., press release, July 7, 2003). In August 2003, Opawica initiated a twenty-hole Phase I diamond drill program. Holes OPW-2 and OPW-3 were drilled on the Pine Centre gold zone. The following results were reported: Hole OPW-2 intersected 15.7 m grading 1.00 g/t Au; Hole OPW-3 intersected 14.5 m grading 1.25 g/t Au. Hole OPW-6, targeting the Pine East zone, intersected 3.2 m grading 3.43 g/t Au and 0.8 m grading 6.39 g/t Au (Opawica Explorations Inc., press release, September 4, 2003) (OFR 6127, p. 26-28, 2004)

May 10, 2016 (Therese Pettigrew) - The Dayton Porcupine Gold Mines holes drilled in 1988 returned assays up to 0.141 opt Au (4.83 g/t Au) over narrow intervals (AFRO 2.50368).

Mineral Record Details

References

Map - Geological series, Straw Lake area, districts of Rainy River and Kenora

Publication Number: P1243 Scale: 1:15,840    Date: 1997

Author: Edwards G.R., Sutcliffe R.H.

Publisher Name: Ontario Geological Survey

Location:

Book - Northern Miner 83-23-08, Sparton

Publication Number: NMINER Date: 1996

Author:

Publisher Name: Northern Miner

Location:

Book - Northern Miner 84-03-29, Sparton, p. 20

Publication Number: NMINER Date: 1996

Author:

Publisher Name: Northern Miner

Location:

Book - Northern Miner 84-05-31, Sparton

Publication Number: NMINER Date: 1996

Author:

Publisher Name: Northern Miner

Location:

Part - Geology of the Straw-Manitou lakes area

Publication Number: ARV43-04 Page: 22-26  Date: 1998

Author: Thomson J.E.

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 Page: 159-160  Date: 1971

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

Publisher Name: Ontario Dept. of Mines and Northern Affairs

Location:

Mono - Gold deposits of the Kenora-Fort Frances area, districts of Kenora and Rainy River

Publication Number: MDC016 Page: 38  Date: 1976

Author: Beard R.C., Garratt G.L.

Publisher Name: Ontario Division of Mines

Location:

Article - 1976 report of the Northwestern Regional Geologist and Kenora Resident Geologist

Publication Number: MP071.001 Page: 8  Date: 1997

Author: Beard R.C., Rivett A.S.

Publisher Name: Ontario Geological Survey

Location:

Mono - Feasibility of small scale gold mining in northwestern Ontario (parts of the districts of Kenora, Rainy River, and Thunder Bay), volume 1, text, volume 2, appendices

Publication Number: OFR5332 Page: 46-47, G-3  Date: 1981

Author: Neilson J.N., Bray R.C.E.

Publisher Name: Ontario Geological Survey

Location:

MonoMap - Geology of the Straw Lake area, districts of Kenora and Rainy River

Publication Number: R222 Page: 59, 61  Date: 1984

Author: Edwards G.R.

Publisher Name: Ontario Geological Survey

Location:

Mono - Geology of the Straw Lake area, districts of Kenora and Rainy River

Publication Number: OFR5292 Page: 105-107  Date: 1980

Author: Edwards G.R.

Publisher Name: Ontario Geological Survey

Location:

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