Ontario Geological Survey
Permanent Link to this Record:
MDI52F11NE00005
| Record Name(s) | North Twin Island - 1986, Longe Occurrence - 1949 |
|---|---|
| Related Record Type | Simple |
| Related Record(s) | |
| Record Status | Occurrence |
| Date Created | 1986-Jul-22 |
| Date Last Modified | 2022-Sep-16 |
| Created By | |
| Revised By |
Primary Commodities: Gold
Township or Area: Buchan Bay Area
Latitude: 49° 41' 10.56" Longitude: -93° 14' 24.47"
UTM Zone: 15 Easting: 482678.813 Northing: 5503776.981 UTM Datum: NAD83
Resident Geologist District: Kenora
NTS Grid: 52F11NE
Point Location Description: General
Location Method: Conversion from MDI
Access Description: The properties are accessible by boat
North Twin Island: History of this occurrence is unknown, but Moorhouse (1941) indicates the presence of the trenches on his Eagle Lake map. Last staked in 1987. Longe Occurrence: 1949: Occurrence discovered, staked, trenched, and sampled by R. Longe. 1954: Staked by H. Wallin. 1955: Magnetometer survey and diamond drilling conducted by Steep Rock Iron Mines Ltd. The company was testing nearby iron formation. 1983: Staked by R. Ferguson. 1984: Transferred to B. Perry 1985: Transferred to J. Pollock. 1987: Staked by W. Sovereign who re-sampled the quartz veins, cleaned out old trenches, and did some manual stripping. (OFR 5723, pg. 234-235)
| Office File Number | Online Assessment File Identifier | Online Assessment File Directory |
|---|---|---|
| Kenora Assessment File 52F/11NE, II-1, Sovereign, | 52F11NE0216 | 52F11NE0216 |
| 12 / Kenora AF52F/11NE, P-1 | 52F11NE0259 | 52F11NE0259 |
| 11 / 52F11NE P-1 | 52F11NE0258 | 52F11NE0258 |
Province: Superior
Geological Age: Precambrian
Nov 02, 2010 (J Bongfelt) - North Twin Island: 'The occurrence is situated immediately north of the contact between the Atikwa Batholith and metavolcanic pyroclastics and flows of the Lower Wabigoon Volcanics.' (OFR 5723, p.261) 'The Longe Occurrence is situated within intermediate and felsic pyroclastics of the Lower Wabigoon Volcanics. The occurrence is a few hundred metres north of the contact between the metavolcanics and granitic rocks of the Atikwa Batholith.' (OFR 5723, p.234)
Nov 02, 2010 (J Bongfelt) - North Twin Island: 'The north shore of the island consists of intermediate to felsic, gray-green, lapilli-tuff and tuff-breccia, sheared 040º to 078º, dipping steeply to the northwest. Massive, gray, medium-to coarse-grained, biotite-hornblende granitic rocks occur immediately south of the metavolcanics and contain large metavolcanic xenoliths. Shallow trenches have been sunk on narrow (0.3 m), linear, shear zones striking 080º/80º NW within the granite and along the granite/metavolcanic contacts. The shear zones host narrow stockworks of milk-white quartz veins containing biotite, dark green chlorite, finely disseminated pyrite [? 1%] and variable amounts of chalcopyrite. The sheared granitic wall rock is typically sericitic, chloritic, and variably pyritic [? 3%] with narrow alteration halos around the veins. Test pits within a mafic metavolcanic xenolith have been sunk on a strong shear zone which hosts disseminated pyrite, pyrrhotite, and minor chalcopyrite in the wall rocks. Narrow (0.3 m), white quartz veins occur throughout the shear zone. The host rocks, in a few of the trenches, are interbedded cherts and tuffs. A few fine-grained, siliceous, gray, quartz-feldspar porphyry dikes intrude the granitic and metavolcanic rocks.' (OFR 5723, pg.261) 'The Longe Occurrence consists of two sets of gold-bearing tension fracture-hosted quartz veins, one set striking 010º to 020º, and the other striking 060º to 070º. The host rocks are intermediate to felsic, heterolithic, pyroclastic breccias intruded by wide north-trending, xenolithic, mafic dikes. The pyroclastic breccias contain huge blocks consisting of mafic pillow breccia and massive magnetite in excess of 2.4 m in width. The main vein sampled by R. Longe is 0.3 m to 0.6 m wide, strikes 010º, and extends from the shore of North Twin Island into the lake. The vein consists of white quartz containing chlorite, tourmaline stringers, and scattered concentrations of chalcopyrite and pyrite.' (OFR 5723, p.234)
| Rank | Mineral Name | Class | Economic Mineral Type | Alteration Mineral Type | Alteration Ranking | Alteration Intensity | Alteration Style |
|---|---|---|---|---|---|---|---|
| 5 | Chalcopyrite | Economic | Ore | ||||
| 10 | Pyrite | Economic | Ore | ||||
| 15 | Tourmaline | Economic | Ore |
Nov 02, 2010 (J Bongfelt) - North Twin Island: 'A grab sample, taken by the author, of carbonatized, sheared granite containing 3% disseminated pyrite assayed 70 ppb gold, while a grab sample from a quartz vein containing 1-3% chalcopyrite and pyrite assayed 5450 ppb gold.' (north centre short location) Longe R. Occurrence: 'Chip samples taken by Mr. Longe across the main vein, at various intervals along an exposed strike length of 50 ft., were reported to assay 0.11, 0.12, 0.70, and 2.38 ounces gold per ton, while a grab sample of the wall rock assayed 0.03 ounce gold per ton. Visible gold was also observed in the vein.' 'Mr. Sovereign (prospector, Dryden, personal communication, 1987) obtained an assay of 0.233 ounce gold per ton from a 22 cm wide chip sample taken across the main vein, but a grab sample taken by the author assayed <0.01 ounce gold per ton. Grab samples from other quartz veins on the property, taken by Mr. Sovereign, assayed 0.206 and 0.655 ounce gold per ton. According to Mr. Sovereign, the best gold assays are associated with chalcopyrite in the quartz veins. Grab samples from other nearby quartz veins taken by the author assayed 0.04 and 0.06 ounce gold per ton.' (OFR 5723, pg.234) 'An 18 inch wide chip sample taken across a quartz vein at the R. Longe Occurrence at the northeast end of North Twin Island assayed 0.40 ounce gold per ton (Kenora Assessment File 52F/11NE, V-1, Fornieri Bay Prospect - Locality 3). This assay has been confused with the North Twin Island Occurrence in past published literature. (OFR 5723, pg.261)
File - Kenora Assessment Files 52F/11NE, W-1, Longe Claim; 52F/11NE, V-1, Fornieri Bay
Publication Number: Date:
Author:
Publisher Name:
Location: Kenora RGP office
Mono - Geology, gold mineralization and property visits in the area investigated by the Dryden-Ignace economic geologist, 1984-1987
Publication Number: OFR5723 Date: 1989
Author: Parker J.R.
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: 42 Date: 1981
Author: Neilson J.N., Bray R.C.E.
Publisher Name: Ontario Geological Survey
Location:
Compend - Report of activities, 1985, Regional and Resident Geologists
Publication Number: MP128 Page: 23,26,28-30 Date: 1986
Author: Kustra C.R.
Publisher Name: Ontario Geological Survey
Location:
We are continuously updating our assessment file / technical report information. If you notice errors in the data, please contact us.
Please review our Terms of Use agreement for this data product.
For detailed information regarding this mineral record please contact the Kenora Resident Geologist District Office