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Ontario Geological Survey
Permanent Link to this Record:
MDI42D09NW00018
| Record Name(s) | Shack Lake Spectrolite - 1992, C. S. Downey Occurrence - 1963, Ferguson Spectrolite - 1975 |
|---|---|
| Related Record Type | Simple |
| Related Record(s) | |
| Record Status | Occurrence |
| Date Created | 1997-Jan-05 |
| Date Last Modified | 2024-Aug-19 |
| Created By | |
| Revised By |
Primary Commodities: Feldspar (Gemstones)
Township or Area: Pic
Latitude: 48° 44' 54.02" Longitude: -86° 21' 52.92"
UTM Zone: 16 Easting: 546701 Northing: 5399674.99 UTM Datum: NAD83
Resident Geologist District: Thunder Bay South
NTS Grid: 42D09NW
Point Location Description: AMIS quarry location
Location Method: Conversion from MDI
Access Description: The occurrence consists of a single patented claim, TB 109470 (NE 1/4, N1/2, Lot 19, Conc. 11), in north-central Pic Township. It is located north of the town of Marathon and can be accessed by road. From Highway 17 drive towards Marathon approximately 1.6 km, take the bush road which leads to the west. Follow the bush road until it ends at the point where Shack Creek exits Shack Lake. The southern boundary of the claim crosses the creek.
1963: C.S. Downey staked a single claim over a schiller feldspar occurrence. 1964: A face was stripped and blasted at the showing. 1965: A pit was blasted and three holes drilled into the showing. Coarse-grained 'labradorite' was intersected in all the holes. 1975: The claim was sent to lease under the name of C.S. Downey. Jon and Audrey Ferguson obtained ownership of claim from Clem Downey. 1989: Cold Spring Granite (Canada) Ltd. drilled 1 DDH totaling 30.8 m. 1992: The Fergusons and Secobel Explorations Inc. formed a working agreement to develop the site. Three holes drilled around the showing, spectrolite was intersected in all three drill holes.
| Office File Number | Online Assessment File Identifier | Online Assessment File Directory |
|---|---|---|
| OP92-230 | 42D16SW0021 | 42D16SW0021 |
| 51 | 42D09NW0307 | 42D09NW0307 |
| 54 | 42D09NE0300 | 42D09NE0300 |
Province: Southern
Geological Age: Mesoproterozoic
Dec 07, 2005 (R Degagne) - The occurrence is underlain by Fe-rich augite syenite (Walker et al. 1992) of the Proterozoic Coldwell Alkalic complex. Geological mapping over the area was done by Puskas (1967) and recently by Walker et al. (1991, 1992). The property was last described in detail by Kustra (1968) and Schnieders et al. (1991).
| Rock Type | Rank | Composition | Texture | Relationship | Syenite | 1 | Fe-Rich Augite Syenite | Medium Grained | Adjacent |
|---|---|---|---|---|
| Syenite | 2 | Syenite | Pegmatite | Host |
Dec 07, 2005 (R Degagne) - The spectrolite occurs within the syenite as two phases: large crystals up to 10 cm across in pegmatite dikes cross-cutting the syenite; and smaller crystals within the contact zone between the pegmatite and medium-grained host syenite (Figure 17). In both cases the spectrolite displays bluish to yellow-gold schillerescence. Ribbe (1983) states, 'Schiller' may be used to refer to diffuse, often silvery reflections from mutually oriented, platy inclusions, especially common in labradorite parallel to (010) (Rayleigh 1923).
| Rank | Mineral Name | Class | Economic Mineral Type | Alteration Mineral Type | Alteration Ranking | Alteration Intensity | Alteration Style |
|---|---|---|---|---|---|---|---|
| 1 | Plagioclase | Economic | Ore | ||||
| 2 | Feldspar | Economic | Ore | ||||
| 1 | Augite | Economic | Gangue |
Dec 07, 2005 (R Degagne) - In 1990 M.C. Smyk, Staff Geologist, Schreiber-Hemlo District, sent a sample for XRD analysis to H. de Souza of the Geoscience Laboratories in Toronto. It was reported, 'X-ray diffraction analysis of the 'spectrolite' shows the presence of plagioclase and minor K-feldspar (anti-perthite). The schiller effects may be brought about by diffraction that occurs at the boundary of exsolution lamellae' (Schnieders et al. 1991).
| Rank | Classification |
|---|---|
| 1 | Pegmatite |
| Rank | Characteristic |
|---|---|
| 1 | Discordant |
Date: Jan 06, 1997
Geologist: R Degagne
Notes: Visited in 1990-1993, 1994 by P. Hinz | R. M. Landry ( OGS OFR 5889, 1994) COMMENTS/RECOMMENDATIONS: Advice was sought by the Ferguson's, in regards to developing their spectrolite property. They are evaluating the property's potential as a pick-your-own tourist operation similar to the amethyst mines near Thunder Bay. A meeting was held with representatives of the Town of Marathon, Secobel Explorations Inc. (potential developers), the Ferguson's, M.C. Smyk (Staff Geologist, Schreiber-Hemlo District) and P. Hinz. Advice was provided on geology, further exploration of the site's potential, marketing, permitting requirements and available funding vehicles for development.
Date: Jul 30, 2024
Geologist: Sheree Hinz
Notes: Site was visited in 2024 by S.Hinz, J.Jonsson, and P.Hinz as part of a historic building stone quarry tour to evaluate future potential economic opportunities in northwestern Ontario. The exposure was overgrown and crumbling. A few samples were taken to be cut and polished,
Map - Port Coldwell area, District of Thunder Bay
Publication Number: P0114 Scale: 1:31,680 Date: 1997
Author: Puskas F.P.
Publisher Name: Ontario Dept. of Mines
Location:
Mono - Industrial Mineral Occurrences and Deposits in Northwest Ontario
Publication Number: OFR5889 Page: 118-120 Date: 1994
Author: Hinz P., Landry R.M.
Publisher Name: Ontario Geological Survey
Location:
Article - Geology of the Coldwell alkaline complex
Publication Number: MP157.018 Date: 1998
Author: Walker E.C., Sutcliffe R.H., Shaw C.S.J., Shore G.T.
Publisher Name: Ontario Geological Survey
Location:
Map - Precambrian Geology, Port Coldwell Complex, East Half
Publication Number: P3233 Scale: 1:20,000 Date: 1993
Author: Walker E.C., Sutcliffe R.H., Shaw C.S.J., Shore G.T., Penczak R.S.
Publisher Name: Ontario Geological Survey
Location:
Article - Geology of the Port Coldwell alkalic complex
Publication Number: MP160.019 Page: 108-120 Date: 1997
Author: Walker E.C., Sutcliffe R.H., Shaw C.S.J., Shore G.T., Penczak R.S.
Publisher Name: Ontario Geological Survey
Location:
MonoMap - Geology of the Port Coldwell area, District of Thunder Bay
Publication Number: OFR5014 Date: 1997
Author: Puskas F.P.
Publisher Name: Ontario Dept. of Mines
Location:
Article - Port Arthur District
Publication Number: MP023.003 Page: 33-80 Date: 1997
Author: Kustra C.R.
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