Ontario Mineral Inventory

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Ontario Geological Survey
Permanent Link to this Record: MDI31F06NE00092

Record: MDI31F06NE00092

General

Mineral Record Identification
Record Name(s)	OGS Sample T-542 - 1978, Lake Clear - 1981
Related Record Type	Simple
Related Record(s)
Record Status	Occurrence
Date Created	1986-Jun-18
Date Last Modified	2023-Jun-16
Created By
Revised By

Commodities

Primary Commodities: Thorium, Uranium, Rare Earth Elements, Cerium, Lanthanum, Neodymium

Location

Township or Area: Sebastopol

Latitude: 45° 28' 34.98" Longitude: -77° 9' 25.78"

UTM Zone: 18 Easting: 331398.002 Northing: 5038135.996 UTM Datum: NAD83

Resident Geologist District: Southern Ontario

NTS Grid: 31F06NE

Point Location Description: approximate

Location Method: Data Compilation

Access Description: Take township roads off Highway 512 west of the town of Eganville. The main area of mineralization is concentrated in lots 31 to 34 in concessions XI and XII Sebastopol Township.

Geology

Province: Grenville

Subprovince: Central Metasedimentary Belt

Geological Age: Mesoproterozoic

Lithology

Lithology Data
Rock Type	Rank	Composition	Texture	Relationship
Pegmatite	1			Host
Quartz Monzonite	2			Contains
Sandstone	3	Arenite	Gneissic	Contains

Lithology Comments

Jun 13, 2011 (A Wilson) - A large quartz monzonite body has intruded syenite and clastic siliceous metasediments. The contact of the metasediments with the quartz monzonite is an area of considerable mixing and local radioactive mineralization is associated with a gradational contact zone from quartz monzonite to arenite. The mixed contact zone contains lenses, irregular pods and patches of pyroxene granophyres and marble, lenses of hornblende-plagioclase gneiss and dikes, veins and patches of granitic and syenitic pegmatite.

Dec 07, 2005 (D Laidlaw) - Radioactive mineralization occurs in the pegmatite and pyroxene veins.

Mineralization

Mineralization and Alteration
Rank	Mineral Name	Class	Economic Mineral Type
1	Allanite	Economic	Ore
2	Chalcopyrite	Economic	Ore
3	Pyrite	Economic	Ore
4	Pyrrhotite	Economic	Ore
5	Thorite	Economic	Ore
6	Uranothorite	Economic	Ore

Mineralization Comments

Jun 13, 2011 (A Wilson) - Sample T-542 collected by the OGS in 1978 returned: 0.29% U3O8, and 10.8% Th. Sample T-542A (albite quartz monzonite) returned 370 ppm Ce, 500 ppm La, 500 ppm Nd, <0.1 ppm Ta and < 5 ppm Sc. Sample T-615 collected by the OGS in 1978 returned 0.68% U3O8, 0.28% K2O, and 13.6% Th. The sample also returned 50 ppm Ce, 300 ppm La, 150 ppm N, <0.1 ppm Ta and <5 ppm Sc. Sample T-617 collected by the OGS in 1978 returned 0.18% U3O8, 1.50% K2O, and 10.1% Th. The sample also returned 1310 ppm Ce, 1500 ppm La, 1500 ppm N, <0.1 ppm Ta and <5 ppm Sc. Sample T-629 collected by the OGS in 1978 returned 0.37% U3O8, 0.56% K2O, and 11.7% Th. The sample also returned 950 ppm Ce, 1000 ppm La, 700 ppm N, <0.1 ppm Ta and <5 ppm Sc. Grab samples collected by Masson and Gordon in 1977 returned 4800 ppm U3O8, and 2.8% Th from R-77-67-2 and 3 ppm U3O8, and 64 ppm Th from R-77-67-3.

Dec 07, 2005 (D Laidlaw) - The mineralized areas are widely spread and numerous, but usually only a square metre or less in size. Grab samples have assayed as high as 0.68% U3O8 but these are selected samples of small concentrations of uranothorite clusters and are not representative of the host rocks in general. (MDC 23, p130).

Mineral Record Details

Classification
Rank	Classification
1	Pegmatite

Characteristics
Rank	Characteristic
1	Intrusive