Ontario Mineral Inventory

Ontario Geological Survey
Permanent Link to this Record: MDI42D14SW00035

Record: MDI42D14SW00035

General

Mineral Record Identification
Record Name(s) Rossport Veins - 1992
Related Record Type Simple
Related Record(s)
Record Status Discretionary Occurrence
Date Created 1997-Feb-07
Date Last Modified 2022-Sep-02
Created By
Revised By

Commodities

Primary Commodities: Barite, Fluorite

Secondary Commodities: Sulphur/Pyrite



Location

Township or Area: Lahontan

Latitude: 48° 50' 26.28"    Longitude: -87° 28' 8.1"

UTM Zone: 16    Easting: 465593   Northing: 5409846    UTM Datum: NAD83

Resident Geologist District: Thunder Bay South

NTS Grid: 42D14SW

Point Location Description: Roadside trenches

Location Method: Field Visit

Access Description: The barite-fluorite veins are located approximately 4 km east of the east Rossport turnoff and 2 km west of the Lakeshore Drive tunoff. The veins crosscut Hwy. 17. The veins outcrop in rock cuts located on the north side of Hwy 17, approximately 4 km east of Rossport, immediately south of the CPR. The veins can also be observed on the shoreline of lake superior.



Exploration History

Pre-1992: trenching; parties unknown. 1992: Geological mapping and lithogeochemical sampling; SH Resident/Staff Geologist (OGS). No assessment reports were found on file.


Geology

Province: Superior

Geological Age: Archean  



Geology Comments

Dec 07, 2005 (D McKay) - The occurrence comprises a number of veins and vein breccias that extend over an exposed width of almost 180 m. The veins range in thickness from <1 cm up to 60 cm and show a fairly consistent orientation between 125 and 160 degrees, parallel to, and sometimes hosted by, steeply dipping joints in pink to grey hornblende + biotite granite. A 1 m wide diabase dike at the western end of the rock cut has a similar orientation.




Lithology

Lithology Data
Rock Type Rank Composition Texture Relationship
Vein 1 Q-Ba-Fl Locally Brecciated And Zoned Host
Granite 2 Host
Diabase 3 Diabase Near

Lithology Comments

Dec 07, 2005 (D McKay) - The granite which hosts the veins is typically pink to grey but is locally saussuritized and in places displays a green epidote colour.




Mineralization

Mineralization and Alteration
Rank Mineral Name Class Economic Mineral Type Alteration Mineral Type Alteration Ranking Alteration Intensity Alteration Style
1BariteEconomicOre
2FluoriteEconomicOre
3PyriteEconomicOre
4GalenaEconomicOre
1QuartzEconomicGangue
EpidoteAlterationSaussuritization1UnknownDisseminated

Mineralization Comments

Dec 07, 2005 (D McKay) - Vein mineralogy is dominated by white quartz; purple fluorite, pink barite and fine-grained, disseminated pyrite and rare galena are minor constituents. The veins appear to have a mineral zonation with fluorite in the center of more barite rich sections. Several composite barite veins contain sulphide zones. Pyrite is the most abundant sulphide, and massive sections of pyrite up to 10 cm wide are observed. Minor galena is also present in on section of the Lakeshore vein. The barite-fluorite +/- sulphide veins are observed across a 150 m section of Trans Canada Hwy. 17. One 3 m wide composite vein strikes 144 degrees and dips 84 degrees southwest. A barite rich section of this vein up to 70 cm wide, strikes 170 degrees and dips 70 degrees west. Grab samples of vein material collected by OGS staff in 1992 returned assay values up to 0.002 ounce Au/ton, trace Ag, 86 ppm Zn, 65 ppm Cu and <10 ppm Pb.



Alteration Comments

Dec 07, 2005 (D McKay) - Anastomosing vein networks and breccias are common and typically display argillic alteration and some epidotization. The granite hosting the veins is locally saussuritized and displays a green epidote colour.




Mineral Record Details

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:


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

Publication Number: OFR5951 Page: 538-539  Date: 1996

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

Publisher Name: Ontario Geological Survey

Location:


File - Resident Geologist files, Schreiber-Hemlo district

Publication Number: Date:

Author:

Publisher Name:

Location: Thunder Bay RGP


Map - Geological series, Precambrian geology of the Schreiber area, west part, Thunder Bay District

Publication Number: P2390 Scale: 1:15,840    Date: 1981

Author: Carter M.W.

Publisher Name: Ontario Geological Survey

Location:


Report an Error

We are continuously updating our assessment file / technical report information. If you notice errors in the data, please contact us.


Terms of Use

Please review our Terms of Use agreement for this data product.


Ministry Contact Information

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