Ontario Geological Survey
Permanent Link to this Record:
MDI31E01SE00224
| Record Name(s) | Bicroft (Croft) - 1987, Croft Uranium - 2000, Croft Mine - 2000 |
|---|---|
| Related Record Type | Simple |
| Related Record(s) | |
| Record Status | Prospect |
| Date Created | 1987-Mar-23 |
| Date Last Modified | 2022-May-11 |
| Created By | |
| Revised By |
Primary Commodities: Uranium
Township or Area: Cardiff
Latitude: 45° 1' 59.75" Longitude: -78° 1' 48"
UTM Zone: 17 Easting: 733945.949 Northing: 4990937.683 UTM Datum: NAD83
Resident Geologist District: Southern Ontario
NTS Grid: 31E01SE
Point Location Description: Adit symbol just NE of property symbol ' 5 ', Lot 32, Con 15.
Location Method: Conversion from MDI
Access Description: From the junction of Hwy 648 and Townline Road, proceed along Townline Road for 3.3 Km and turn right onto the mine road. The adit and dumps are at 1.8 Km from the turn.
1953-4 : Croft Uranium Mines Ltd completed an airbourne scintillometer survey and a 1,585 ft adit at 70 ft below surface into the J Zone. Underground work included 1,211 ft of drifts, 485 ft of crosscuts and 93 DDH ( 3,053 ft ). Surface work included trenching and 40,117 ft of drilling in 115 holes. 1975 : Kerr Addison completed a radon gas survey, experimental leaching and 44 DDH ( 17,766 ft ). 1977-8 : Kerr Addison continued drilling for a total of 48,745 ft.
Province: Grenville
Geological Age: Mesoproterozoic
Dec 07, 2005 (C Papertzian) - Mineral location. The Croft property lies in a belt of syenitized paragneiss and amphibolite. The metasediments strike at N10E and dip 45-65 degrees SE. They comprise hornblende gneiss, amphibolite, biotite paragneiss and biotite-garnet-sillimanite gneiss. They are cut and replaced by irregular syenite and granite dykes. Uranium mineralization occurs in shoots within complex, pegmatitic granite dykes. There are 5 main radioactive zones with the J, or Adit Zone, being the most important. The zones range in length from 90-580 ft and occur along the contacts of pods of biotite-garnet-sillimanite gneiss. The dykes are biotite-granite pegmatite in which the feldspar shows porphyroblastic texture. Uranothorite occurs with accessory zircon, pyrite and molybdenite. The J Zone is 1,500 ft long , 40 ft wide and averages 0.57 lbs U3O8 per ton. It is estimated to contain reserves of 800,000 short tons.
| Rock Type | Rank | Composition | Texture | Relationship | Pegmatite | 1 | Contains |
|---|
| Rank | Mineral Name | Class | Economic Mineral Type | Alteration Mineral Type | Alteration Ranking | Alteration Intensity | Alteration Style |
|---|---|---|---|---|---|---|---|
| 5 | Corundum | Economic | Ore | ||||
| 10 | Garnet | Economic | Ore | ||||
| 15 | Molybdenite | Economic | Ore | ||||
| 20 | Pyrite | Economic | Ore | ||||
| 25 | Sillimanite | Economic | Ore | ||||
| 30 | Uranothorite | Economic | Ore | ||||
| 35 | Zircon | Economic | Ore |
Book - Canadian deposits of uranium and thorium; Geological Survey of Canada, Economic Geology Series 16
Publication Number: Econ Geol 16 Page: 179-182 Date: 1962
Author: Lang, A H; Griffith, J W; Steacy, H R
Publisher Name: Geological Survey of Canada
Location: https://doi.org/10.4095/102450
Part - Radioactive mineral occurrences in the Bancroft area
Publication Number: ARV65-06 Page: 37-40 Date: 1998
Author: Satterly J., Hewitt D.F.
Publisher Name: Ontario Dept. of Mines
Location:
Part - Geology of Cardiff and Faraday townships
Publication Number: ARV66-03 Page: 61 Date: 1998
Author: Hewitt D.F.
Publisher Name: Ontario Dept. of Mines
Location:
Mono - Uranium and thorium deposits of southern Ontario
Publication Number: OFR5311 Page: 82-84 Date: 1981
Author: Gordon J.B., Rybak U.C., Robertson J.A.
Publisher Name: Ontario Geological Survey
Location:
MonoMap - Industrial minerals of the Algonquin region
Publication Number: OFR5425 Page: P12,90,260,295 Date: 1983
Author: Martin W.
Publisher Name: Ontario Geological Survey
Location:
Mono - Granitic pegmatites of the Bancroft area, southeastern Ontario
Publication Number: OFR5717 Page: 112 Date: 1990
Author: Goad B.E.
Publisher Name: Ontario Geological Survey
Location:
Book - Resident Geologist files 1953, AFRO # 50
Publication Number: Date: 2000
Author:
Publisher Name:
Location: Tweed RGP
Book - Resident Geologist files 1976,85, AFRO # 153, 211
Publication Number: Date: 2000
Author:
Publisher Name:
Location: Tweed RGP
Publication - Rocks and minerals for the collector: Bancroft - Parry Sound area and southern Ontario; Geological Survey of Canada, Miscellaneous Report 39
Publication Number: GSC MR 39 Page: 86 Date: 1986
Author: Sabina, A P
Publisher Name: Geological Survey of Canada
Location: https://doi.org/10.4095/121046
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