Ontario Mineral Inventory

Ontario Geological Survey
Permanent Link to this Record: MDI42E03SW00023

Record: MDI42E03SW00023

General

Commodities

Primary Commodities: Gold

Secondary Commodities: Silver, Copper, Zinc, Tungsten

Location

Township or Area: Rope Lake Area, Pays Plat Lake Area

Latitude: 49° 0' 1.06"    Longitude: -87° 18' 32.76"

UTM Zone: 16    Easting: 477391.77   Northing: 5427534.64    UTM Datum: NAD83

Resident Geologist District: Thunder Bay South

NTS Grid: 42D14NW, 42E03SW

Point Location Description: Trench

Location Method: Field Visit

Access Description: The prospect is located along an old winter road (now a foot trail) approximately 1.6 km west of Big Duck Lake, and about 21 km north-northwest of Schreiber (claim maps G-606 and G-609, Pays Plat Lake and Rope Lake, respectively). On the Corporation Falconbridge grid the Coco-Estelle showing is located on line 14+50W at 8+50S. Access to Big Duck Lake is via a drill road from the Winston Lake Mine road which extends from Highway 17 8 km west of Schreiber. Easiest access is by float plane to Big Duck lake or by helicopter to the showing area.

Exploration History

1914-1915: Prospecting, trenching and other unspecified surface work; A. Estelle. 1919: Patent granted for claim TB 2093, but revoked in 1938. 1945-1946: Diamond drilling (8 holes totalling 161.5 m); Sandenise Gold Mines Limited. The drilling was focused on the Coco showing. 1951-1959: The occurrence was staked several times by various individuals but no work was recorded. 1959: Diamond drilling (13 holes totalling 810 m); KRNO Mines Limited. The drilling was focused on the Coco Zone. 1959-1960: Diamond drilling (56 holes totalling 4500 m); Kinasco Mines. The drilling was focused on the Coco-Estelle and Church zones. 1960: Diamond drilling (17 holes totalling 1948.4 m); KRNO Mines Limited. 1975: Mid-North Engineering Services Ltd. drilled 4 DDH totalling 342.9 m on the Coco-Estelle showing. 1980-1984: Various geological, geophysical and geochemical surveys; Noranda Exploration Company Limited. 1983-1987: Geological, geophysical and geochemical surveys and diamond drilling (8 holes totalling 1686 m); Corporation Falconbridge Copper. 1983, 1985: Property examination and lithogeochemical sampling; OGS Resident Geologist staff. 1990: Ground geophysical survey (IP); Corporation Falconbridge Copper. MSc thesis work; D. Ritchie. 1993: Diamond drilling (3 holes totalling 562 m); Metall Mining Corporation and Rusty Lake Resources. 2003: Tri-Alpha Exploration conducted a trenching program. 2005: Tri Gold Resources completed an IP survey. 2006: Tri Gold drilled 5 DDH and conducted a field program consisting of trench mapping, channel sampling, drilling and petrographic work. 2010: staked by a group of prospectors (Clear Gold Resources Inc.). 2012: Clear Gold conducted prospecting. 2013: Clear Gold conducted prospecting and sampling.

Assessment Work on File

Geology

Province: Superior

Subprovince: Wawa

Terrane: Wawa-Abitibi

Belt: Schreiber-Hemlo

Geological Age: Archean  

Geology Comments

Dec 07, 2005 (D McKay) - Pye (1964, pp.29-30) described the geology of the Coco-Estelle deposit as follows: The Coco-Estelle deposit is in hornblende schist, along or close to the north contact of a large sill-like body of quartz porphyry. It strikes N.80 -85 degrees and dips 65 -70 degrees N. It has been tested in the diamond-drillholes, at intervals of 15-250 feet, over a length of 950 feet. Surface exposures and the drill cores show it to be a zone, averaging 15-20 feet in thickness, of hornblende schist with about 5 percent disseminated fine-grained pyrite and small amounts of pyrrhotite, chalcopyrite and sphalerite. The mineralized schist is cut at frequent and irregular intervals by thin stringers and 'threads' of quartz and quartz carbonate. Also present are veins or lenses of quartz, similar in every way to other quartz veins found in the Big Duck Lake area. Some of these veins or lenses are several feet thick and they appear to be most abundant and widest near the margins of the deposit; in several drillholes the deposit was found to be made up of two quartz veins separated 5-10 feet of mineralized hornblende schist. Although the quartz veins do not appear to contain as much sulphides as the wall rock, much of the gold found in the deposit is associated with them, because in several cases high assay-values and the occurrence of quartz-vein material were found to be coincident. Visible gold was observed in the core from diamond- drillhole C-5 (Ringsleben 1959), but in general the gold is finely divided and cannot be seen with the unaided eye.

Feb 27, 2015 (Therese Pettigrew) - The Schreiber- Hemlo Greenstone Belt is dominated by east-west striking lithologic units (mostly volcanic and sedimentary units). The Schreiber Assemblage, of which the Big Duck Lake area is a component, is defined as the volcanic and associated sedimentary rocks found on the west side of the Coldwell Alkalic Intrusive Complex and the Hemlo assemblage are similar rocks found on the east side of the Coldwell Complex. The greenstone belt is bounded, and partly intruded by, granitic to granodioritic intrusions, related gneisses and pegmatites. Most of these are large, complex batholiths and are thought to postdate the emplacement of the greenstones by up to 100 Ma. The Coldwell Alkalic Intrusive Complex is much younger, about 1100 Ma old (Clark, 2013; AFRO 2.54658).

Lithology

Lithology Comments

Dec 07, 2005 (D McKay) - Schnieders et al. (1996) state: The country rocks consist of mafic to intermediate metavolcanics, mainly pillowed flows, massive flows, pillow breccia and hyaloclastite. Pillows indicted a north facing direction. Metasediments are presumed to be present in the area. The host metavolcanic rocks have been altered and now comprise hornblende and biotite schist. The biotite-rich rocks may represent massive potassic alteration. A sample of biotite schist displays disseminated pyrite up to 3-5% as well as numerous folded and deformed quartz-carbonate veins. A green mineral is present within the quartz-carbonate veins and minor chalcopyrite was noted. Several of the quartz veins are crosscutting and at least two ages of veining is likely. The mafic to intermediate metavolcanics have been intruded by quartz-feldspar porphyry. The porphyry sills appear to parallel the bedding and are likely closely related in time to a synvolcanic-sublayer felsic intrusion. A quartz vein up to 1 m in width is present within the main pit, hosted by the mafic schist. Inclusions of the schist are present within the quartz, with the mineralization consisting of pyrite, chalcopyrite and possible sphalerite. Accessory minerals include calcite, biotite, epidote, actinolite and sericite. An unidentified green mica or carbonate mineral was observed. The sulphide mineralization observed makes up to 10 percent of the quartz vein and mineralized mafic schist in the main pit area. The quartz has a sugary, recrystallized appearance.

Mineralization

Mineralization Comments

Dec 07, 2005 (D McKay) - Schnieders, et al. (1996) state: Drilling by Corporation Falconbridge Copper of the Coco-Estelle gold zone revealed the presence of sulphide mineralization which ranged from trace amounts and disseminations to semi-massive concentrations where total sulphide content is 30-40 percent. Sulphide minerals include pyrite, pyrrhotite, chalcopyrite and reddish-brown sphalerite. Mineralization is commonly associated with biotite-carbonate-amphibole alteration zones and carbonate-epidote-quartz veins. Ringlesben and Burns (1959, assessment files) noted that: Both the quartz and the adjacent schist are mineralized with fine grained pyrite. Minor amounts of chalcopyrite and sphalerite occur in the quartz at the large pit. Fine visible gold was found in (KRNO Mines Limited) hole No. 5. Important [gold] values have been intersected for a length of 220 feet and this may be extended. Grab samples collected from the occurrence by OGS Resident Geologist staff in 1983 and 1985 returned assay values which varied from 0.01 to 0.55 opt Au, <0.10 to 0.67 opt Ag, 29 to 1350 ppm Cu, 20 ppm Pb, 65 to 104 ppm Zn, 22 ppm Co and 12 ppm Ni. KRNO Mines Ltd. reported drill intercepts of up to 3.2 opt Au over 1.25 m (hole C-5) and 1.22 opt Au over 3.0 m (hole CH-14). Metall Mining Corporation reported drill intercepts of up to 4.3 opt Au over 1.7 m (hole BD-56) and 1.23 opt Au over 11.65 m (hole BD-57). Lewis (1993) stated that the Coco-Estelle zone was a 700 metre east-west structure with a small localized reserve of 53 700 tonnes at a grade of 10.7 g/t Au. This zone which varies in width from 25 to 50 m and exhibits strong foliated, pervasive biotite alteration. From the longitudinal section it appears that the mineralized zone has a shallow westerly plunge and the zone has been drilled to a maximum longitudinal depth of 200 m.

May 28, 2019 (Therese Pettigrew) - Sheelite has been found in surface exposures and in the drillhole cores and one grab sample from the Coco-Estelle desposit is reported to have yielded on analysis more than 5 percent WO3 (Pye, 1961). Samples collected by Clear Gold in 2013 returned assays of up to 35.257 ppm Au, 5570 ppm Cu, and 43 ppm Ag (Assessment report 20000008066).

Alteration Comments

Dec 07, 2005 (D McKay) - Mineralization is commonly associated with biotite-carbonate-amphibole alteration zones and carbonate-epidote-quartz veins.

Mineral Record Details

Mineral Zones - Size and Shape

References

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:

MonoMap - Mineral deposits of the Big Duck Lake area, District of Thunder Bay

Publication Number: R027 Page: 29-30  Date: 1997

Author: Pye E.G.

Publisher Name: Ontario Dept. of Mines

Location:

File - Schreiber-Hemlo Resident Geologist Mineral Deposit Files

Publication Number: Min Dep Date:

Author:

Publisher Name:

Location: Thunder Bay RGP

Map - Big Duck Lake area, District of Thunder Bay

Publication Number: M2023 Scale: 1:15,840    Date: 1997

Author: 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 Page: 291  Date: 1971

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

Publisher Name: Ontario Dept. of Mines and Northern Affairs

Location:

Map - Big Duck-Aguasabon lakes area, District of Thunder Bay, Ontario

Publication Number: ARM49K Scale: 1:31,680    Date: 1997

Author: Bartley M.W.

Publisher Name: Ontario Dept. of Mines

Location:

Mono - Mineral Occurrences in the Nipigon-Marathon Area, Volumes 1 and 2.

Publication Number: OFR5951 Page: 800-809  Date: 1996

Author: Schnieders B.R., Smyk M.C., Speed A.A., McKay D.B.

Publisher Name: Ontario Geological Survey

Location:

Part - Statistical review of the mineral industry of Ontario for 1914

Publication Number: ARV24-01.001 Page: 9-13  Date: 1998

Author: Gibson T.W.

Publisher Name: Ontario Bureau of Mines

Location:

Compend - Report of activities, 1983, Regional and Resident Geologists

Publication Number: MP117 Page: 92  Date: 1984

Author: Kustra C.R.

Publisher Name: Ontario Geological Survey

Location:

Map - Schreiber sheet, District of Thunder Bay, geological compilation series

Publication Number: P0360 Scale: 1:126,720    Date: 1997

Author: Pye E.G.

Publisher Name: Ontario Dept. of Mines

Location:

Mono - Mineral deposits of the Big Duck Lake area, District of Thunder Bay

Publication Number: PR1961-01 Date: 1998

Author: Pye E.G.

Publisher Name: Ontario Dept. of Mines

Location:

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