Ontario Mineral Inventory

Ontario Geological Survey
Permanent Link to this Record: MDI52O04NE00021

Record: MDI52O04NE00021

General

Mineral Record Identification
Record Name(s)	Loon - 9999, Wesleyan Lake #1 - 1986, Loon Prospect - 1986, Bemaji Lake - 9999
Related Record Type	Simple
Related Record(s)
Record Status	Occurrence
Date Created	1986-Dec-11
Date Last Modified	2022-Sep-27
Created By
Revised By

Commodities

Primary Commodities: Molybdenum

Secondary Commodities: Gold, Copper, Silver

Location

Township or Area: Wesleyan Lake Area

Latitude: 51° 8' 53.87" Longitude: -91° 30' 10.21"

UTM Zone: 15 Easting: 604717.694 Northing: 5667381.913 UTM Datum: NAD83

Resident Geologist District: Thunder Bay North

NTS Grid: 52O04NE

Point Location Description: Trenches.

Location Method: Conversion from MDI

Access Description: The Loon Prospect is located about 96 km west-southwest of Pickle Lake and about 5.6 km east-southeast of the First Nation community of Slate Falls. It is on the south shore of North Bamaji Lake. Access to this occurrence is by appropriately equipped aircraft to North Bamaji Lake. A winter road along the Ear Falls to Pickle Lake power corridor passes about 2.8 km north of the Loon prospect.

Exploration History

The Loon Prospect was discovered by the Loon family from the First Nation Community of Slate Falls in the early 1960s. 1965: Claims covering the prospect were jointly optioned by Cochenour Willans Gold Mines Ltd. and Coin Lake Gold Mines Ltd. They conducted a program of line-cutting, stripping and trenching, geological mapping and diamond-drilling that continued through 1966. A total of 9 diamond-drill holes tested the Loon Prospect with an aggregate length of 630 m. An additional 3 diamond-drill holes, totalling 155 m, tested other showings about 600 m to the east. 1989: Umex Inc. commissioned airborne mag and EM surveys which included the area of the Loon Prospect.

Geology

Province: Superior

Subprovince: Uchi

Terrane: North Caribou

Domain: Uchi

Belt: Meen-Dempster

Geological Age: Archean

Geology Comments

Dec 07, 2005 (B Nelson) - Sulphide mineralization occurs in a complex series of quartz veins and discontinuous lenses and to a minor extent in the adjacent country rock which is sheared, recrystallized, leucocratic, biotite trodhjemite. The quartz veins are subvertical and strike between 75 degrees and 85 degrees. Trondhjemite directly adjacent to the veins is typically highly schistose and rich in sericite. The contacts vary from sharp to gradational even along the length of individual veins, and the veins tend to be very irregular in terms of both size and shape. At the main showing the largest vein pinches and swells in an en echelon manner over an exposed length of 13 m, reaching a maximum width of 1 m. This and other smaller veins nearly change orientation, eratically varying from subparallel to highly discordant with respect to the strong east-west foliation of the trondhjemite.

Lithology

Lithology Data
Rock Type	Rank	Composition	Texture	Relationship
Tonalite	1	Trondhjemite		Host

Lithology Comments

Dec 07, 2005 (B Nelson) - No other associated rock types.

Mineralization

Mineralization and Alteration
Rank	Mineral Name	Class	Economic Mineral Type	Alteration Mineral Type	Alteration Ranking
1	Chalcopyrite	Economic	Ore
2	Molybdenite	Economic	Ore
3	Pyrite	Economic	Ore
4	Sphalerite	Economic	Ore
1	Quartz	Economic	Gangue
	Sericite	Alteration		Unknown	1
	Malachite	Alteration		Unknown	2
	Limonite	Alteration		Unknown	3

Mineralization Comments

Dec 07, 2005 (B Nelson) - Molybdenite occurs within the quartz veins along with abundant disseminated and massive pyrite and sparsely distributed chalcopyrite. Ferrimolybdite, limonite and malachite are common alteration products present in several localities. The Mo itself forms fine- to very fine-grained disseminations in blue-grey quartz, and also occurs in narrow seams and veinlets, and in massive clots up to 3 cm in diameter. Minor Mo stringers and disseminations are found in the adjacent country rock. The amount and type of sulphide minerals present vary markedly within and between individual veins. In the best mineralized examples mo forms up to 5 percent of the vein material. Sage and Breaks (1982) took four grab samples from the Loon Prospect. Assay values ranged from 0.05 to 3.28% Mo, from 0.45 to 2.91% Cu, from 0.02 to 0.18 oz/ton Au and from 0.94 to 9.49 oz/ton Ag. Assay results from the 1966 drilling of the prospect were generally less than 0.12% Mo. The best assay result from the drilling was 2.53% Mo over 79 cm.

Alteration Comments

Dec 07, 2005 (B Nelson) - Also noted is the presence of ferrimolybdite.

Mineral Record Details

Classification
Rank	Classification
1	Porphyry

Characteristics
Rank	Characteristic
1	Vein

References

Map - Cat Lake-Pickle Lake, geological compilation series, Kenora and Thunder Bay districts

Publication Number: M2218 Scale: 1:253,440 Date: 1976

Author: Sage R.P., Breaks F.W., Troup W.R.

Publisher Name: Ontario Division of Mines

Location:

MonoMap - Geology of the Cat Lake-Pickle Lake area, districts of Kenora and Thunder Bay

Publication Number: R207 Page: 76 Date: 1982

Author: Sage R.P., Breaks F.W.