Ontario Mineral Inventory

Ontario Geological Survey
Permanent Link to this Record: MDI52L07SE00030

Record: MDI52L07SE00030

General

Commodities

Primary Commodities: Lithium, Rubidium

Secondary Commodities: Cesium, Niobium, Tantalum, Tin

Location

Township or Area: Paterson Lake Area

Latitude: 50° 15' 45.33"    Longitude: -94° 33' 55.8"

UTM Zone: 15    Easting: 388420   Northing: 5569000.01    UTM Datum: NAD83

Resident Geologist District: Kenora

NTS Grid: 52L07SE

Point Location Description: Pegmatite occurs 60 km north of Kenora on an all-weather road.

Location Method: Data Compilation

Access Description: Since the deposit is near the south shore of Separation Lake, access is by water from the Separation Rapids Narrows bridge. The bridge is 5 km east of the deposit. The bridge is part of the English River logging road. This bridge is located 50 km north of Kenora.

Exploration History

1996: Discovery by OGS and staked by prospectors R. Fairservice and J. Willis. Property optioned by Avalon Ventures in Oct 1996. 1997: Avalon conducted geological mapping, trenching, sampling and diamond drilling. 1998-99: Avalon conducted an exploration program including drilling 69 DDH totalling 10,152 m, geological mapping, trenching, ground magnetic surveys, mineralogical studies, delineated petalite resource, Micon completed pre-feasibility study. 2002: bulk sample extracted. 2008-11: Consolidated land position and secured mining lease. 2009: Changed name to Avalon Rare Metals. 2012: Avalon purchased 2% NSR from prospectors. 2013-14: signed memorandum of understanding with Wabaseemoong Independent Nations. 2016: Avalon carried out a petrographic study and a Preliminary Economic Assessment. 2017: Avalon drilled 5 DDH totalling 1473 m. 2018: Avalon drilled 6 DDH totalling 1548 m. 2022-23: Avalon Advanced Materials Inc. drilled 13 DDH totalling 4179 m. 2023-25: Avalon drilled 29 DDH totalling 8921 m.

Assessment Work on File

Geology

Province: Superior

Subprovince: English River

Belt: Separation Lake

Geological Age: Archean  

Geology Comments

Feb 09, 2011 (C Ravnaas) - Granitoid rocks of the Separation Rapids pluton, emplaced into the volcanic belt in the vicinity of the English River, 4 km west northwest of Separation Rapids, are predominantly pegmatitic to coarse grained, with some aplitic phases. They are pink to white in colour, and vary in composition from granites to granodiorites to tonalites, though colour is not a good discriminant. Garnet is present in the more plagioclase--rich varieties, in both aplites and pegmatites. Pale green beryl was found in garnet-bearing tonalites by the present survey, and Breaks (1993) subsequently found other occurrences of beryl and other rare metal bearing minerals (see section on rare metals). Muscovite is the predominant mica, especially in tonalite. Large pink blocky potash feldspar crystals are common in and define granodioritic and granitic pegmatites and coarse grained phases can be megacrystic. Layering, defined by crystal size and composition, is common. (from OFR 6001 p 14).

Lithology

Lithology Comments

Feb 09, 2011 (C Ravnaas) - Southwest Petalite Zone, The pegmatite consists of 4 zones: aplite wall zone, megacrystic K-feldspar zone, quartz-muscovite zone and petalite zone (80 vol% of the pegmatite). the petalite occurs primarily in 2 units: 1. K-feldspar-petalite zone (minor quartz and muscovite) and 2. Monomineralic lenses in garnet-muscovite aplite. The first zone consists of alternating zones of K-feldspar-petalite with lenses of much finer-grained muscovite aplite. The second zone is characterized by pink petalite layers hosted within garnet-quartz-muscovite-albite aplite. The pegmatite field associated with the pluton extends eastward at least as far as the English River Road, and possibly westward on the order of 2 km from the English River, where muscovite and garnet bearing bodies, mappable at the current scale, occur. Green beryl was found in one such pegmatite in this area. Further extension of the field is indicated by an unconfirmed green beryl occurrence (a single crystal observed in outcrop but not sampled) in pegmatitic granite within the Tourist Lake granites, outcropping along the creek flowing northward into Storm Bay at its east end. A confirmed occurrence of green beryl (X--ray diffraction of several grains), at one location only, in pegmatite on the peninsula east of Fiord Bay, greatly increases the possible extent of the field generated by the Separation Rapids pluton. (from OFR 6001 P.14)

Mineralization

Mineralization Comments

Dec 23, 2014 (C Ravnaas) - The ore minerals are petalite (1), feldspar (1), ferrocolumbite (2), ferrotantalite (2), manganotantalite (2), ferrotapiolite (2), ferrowodginite (2), cassiterite (2), beryl (3). The pegmatite contains abundant quartz, K-feldspar, albite, petalite, lepidolite, muscovite; accessor spodumene, beryl, garnet (spessartine), fluorapatite, oxides; and rare siderophyllite-zinnwaldite, eucryptite, monazite, zircon, fluorite, topaz. The accessory oxide minerals include: ferrocolumbite, ferrotantalite, manganocolumbite, manganotantalite, microlite, cassiterite, gahnite, nigerite. The geological mapping and diamond drilling work done by Avalon have delineated the Big Whopper pegmatite system over a strike length exceeding 1.5 km, with widths ranging from 10 m to 80 m and to a vertical depth of close to 300 m, where it remains open. It consists of a vertically oriented massive petalite pegmatite dyke striking 280º, hosted by metamorphosed mafic volcanic rocks (amphibolite) and flanked by a swarm of narrower albite and petalite dykes. These have all undergone intense deformation in a high strain zone resulting in folding, boudinage, and shearing. The mineralized zone is well exposed at surface in a low dome-shaped hill, where it averages 55 m in width over a 400 m strike length, and will, therefore, be readily amenable to mining by low-cost quarrying methods. A conceptual open pit designed for the pre-feasibility study by Micon International contains a probable reserve of 7.72 million tonnes grading 1.4% Li2O, which is the reserve used for present planning purposes (from Avalon Ventures Annual Report 2007). Bulk analysis of the petalite revealed 4.74 wt.% Li2O (Breaks and Tindle 2001). the petalite zone contains an average of 1.58wt.% Li2O over 59.8 m with the petalite making up 37 vol% of the zone (Breaks and Tindle 1997). Bulk analysis of K-feldspar revealed an average of 198 ppm Cs, 13310 ppm Rb and 8.2 K/Rb for 7 samples (Breaks and Tindle 2001). Bulk analysis of muscovite-quartz-K-feldspar-petalite zone (96-29) revealed 6822 ppm Li, 2224 ppm Rb, 124 ppm Sn, 69 ppm Nb, 55 ppm Ta and 1.25 Nb/Ta (Breaks and Tindle 2001). Bulk analysis of the pegmatite (DDH 97-2) revealed 3200-11000 ppm Li, 2078-6908 ppm Rb, 15-146 ppm Cs, 33-59 ppm Ga, 100-1300 ppm Sn, 22-139 ppm Nb, 14-204 ppm Ta and 210-8000 ppm F (Pedersen et al. 2001). Bulk whole rock analysis of metasomatic selvedges contained between 1000ppm to 1.4 wt.% Cs2O. Microlite contained 50-72 wt.% Ta2O5, columbite-tantalite 13-83 wt.% Ta2O5, wodginite 45-69 wt.% Ta2O5, tapiolite 70-82 wt.% Ta2O5, cassiterite 0.6-9 wt.% Ta2O5. Geological mapping and diamond drilling by Avalon Venture Ltd. has delineated the Big Whopper pegmatite system over a strike length of 1.5 km with widths ranging from 10 to 80 m and a vertical depth of approximately 300 m, where it remains open. The drill program defined a total petalite resource calculated at 11.6 million tonnes grading 1.34% lithium, 0.30% rubidium. The principle commodities identified to 2001 are petalite, tantalum and rubidium-rich potassium-feldspar.

May 04, 2023 (Therese Pettigrew) - The winter 2022/23 diamond drilling program included twelve drill holes on the existing resource and one vertical drill hole on the main centre of the deposit designed to examine the potential depth extent of the petalite mineralization. Twelve holes were designed to undercut historic maximum-known mineralized drill intercepts on the widest part of the Separation Rapids as step outs to expand the existing resource. The main deposit consists of a large, zoned vertical pegmatite dyke averaging 50-70m in thickness that has been structurally flattened, that includes both petalite and lepidolite accompanied by many narrower mineralized dykes of similar but variable lithium mineralogy. The dominant lithium mineral is petalite. The dykes tend to be lepidolite-rich on both the east and west extensions. drilling tested the deposit to depth, over a 300 m strike length in the main part of the deposit (“The Big Whopper”) with mineralization exceeding the 0.5% Li2O cutoff grade encountered in all but one of the holes. Notable mineralized intervals (all widths estimated true width unless otherwise stated) include 1.67% Li2O over 19.6 m. Drilling tested the deposit to depth, over a 300 m strike length in the main part of the deposit (“The Big Whopper”) with mineralization exceeding the 0.5% Li2O cutoff grade encountered in all but one of the holes. Notable mineralized intervals (all widths estimated true width unless otherwise stated) include 1.67% Li2O over 19.6 m (SR-22-81), 1.20% Li2O over 27.5 m (SR-23-83) and 1.8% Li2O over 9.63 m contained within 0.96% Li2O over 45 m (SR-23-86). For the eastern extension of the deposit, SR-23-89 intersected 1.61% Li2O over 5.74 m and for the western extension SR-23-92 intersected intervals of 0.89% Li2O over 12.4 m and 1.49% Li2O over 4.5 m. (SR-22-81), 1.20% Li2O over 27.5 m (SR-23-83) and 1.8% Li2O over 9.63 m contained within 0.96% Li2O over 45 m (SR-23-86). For the eastern extension of the deposit, SR-23-89 intersected 1.61% Li2O over 5.74 m and for the western extension SR-23-92 intersected intervals of 0.89% Li2O over 12.4 m and 1.49% Li2O over 4.5 m. Drill hole SR-23-93 was set up near the geographic centre of the deposit and drilled vertically to 570 m. As mentioned above, the objective was to explore geologically the depth extent of the Big Whopper pegmatite assuming it continues with a vertical dip. The deepest intercept prior to this drill program was about 315 m from surface. The vertical drill hole intersected pegmatite to a depth of 565 m with continuous visible petalite mineralization similar to previous assayed core intervals along its entire length. The drill hole exited pegmatite entering amphibolite host rock at 565 m. This intercept does not represent true width (Avalon Advanced Materials news release, May 4, 2023).

Alteration Comments

Jul 13, 2010 (C Ravnaas) - The alteration minerals are holmquistite and albite

Assay Samples

Mineral Record Details

Mineral Zones - Size and Shape

References

Publication - Rare-Element Mineralization of the Separation Lake Area: Characteristics Of A New Discovery Of Complex Type, Petalite Subtype, Li-Rb-Cs-Ta Pegmatite; In: Industrial Minerals in Canada: CIM Special Volume 53, p. 159-178.

Publication Number: CIM VOL. 53 Date: 2001

Author: Breaks, F.W., and Tindle, A.G.

Publisher Name: Canadian Institute of Mining, Metallurgy and Petroleum

Location:

Map - Geological series, Operation Kenora-Sydney Lake, Umfreville-Separation lakes sheet, District of Kenora

Publication Number: P1028 Scale: 1:63,360    Date: 1975

Author: Breaks F.W., Bond W.D., McWilliams G.H., Gower C.F., Findlay D.C., Stone D.

Publisher Name: Ontario Division of Mines

Location:

Publication - The Big Whopper Petalite Deposits, A Major New Rare Metal Pegmatite, Separation Rapids, Northwestern Ontario; In: Industrial Minerals in Canada: CIM Special Volume 53, p. 179-186

Publication Number: CIM VOL 53 Date: 2001

Author: Pederson, J.C., Taylor, R.P., and Campbell, I.J.

Publisher Name: Canadian institute of Mining, Metallurgy and Petroleum

Location:

Mono - Rare-Metal Exploration Potential of the Separation Lake Area: An Emerging Target for Bikita-Type Mineralization in Superior Province, Northwestern Ontario

Publication Number: OFR5966 Date: 1997

Author: Breaks F.W., Tindle A.G.

Publisher Name: Ontario Geological Survey

Location:

Publication - NI 43-101 Technical Report on the Preliminary Economic Assessment for the Production of Petalite Concentrate from the Separation Rapids Lithium Dpeosit, Kenora, Ontario

Publication Number: 2018 NI 43-101 Date: 2018

Author: Gowans, R., Jacobs, C., Ing, E., Pilcher, B., Spooner, J., Aiken, S.R., Haw

Publisher Name: Micon for Avalon Advanced Materials

Location: SEDAR

Book - Columbite-Tantalite Mineral Chemistry from Rare-Element Granitic Pegmatites: Separation Lake Area

Publication Number: Min & Pet v70 Date:

Author: Tindle, A.G. and Breaks, F.W.

Publisher Name:

Location:

Map - Geology of Marko's Pegmatite, Separation Rapids Pegmatite Group, Separation Lake Greenstone Belt

Publication Number: P3302 Scale: 1:100    Date: 1994

Author: Breaks F.W., Nurmikivi M., Burton J., Robitaille A.

Publisher Name: Ontario Geological Survey

Location:

Map - Precambrian Geology, Separation Lake Greenstone Belt-West Sheet

Publication Number: P2673 Scale: 1:20,000    Date: 2008

Author: Blackburn C.E., Young J.B., Breaks F.W.

Publisher Name: Ontario Geological Survey

Location:

Map - Precambrian Geology, Werner Lake-English River Area

Publication Number: M2516 Scale: 1:50,000    Date: 1997

Author: Beakhouse G.P.

Publisher Name: Ontario Geological Survey

Location:

Map - Precambrian Geology, Separation Lake Greenstone Belt, West Part

Publication Number: OFM0241 Scale: 1:20,000    Date: 1994

Author: Blackburn C.E., Young J.B., Searcy T.O., Donahue K.

Publisher Name: Ontario Geological Survey

Location:

Map - Geological series, western English River Subprovince and parts of Uchi and Wabigoon subprovinces, general geology and lithophile type mineralization, districts of Kenora and Kenora (Patricia Portion)

Publication Number: P1971 Scale: 1:253,440    Date: 1997

Author: Breaks F.W., Bond W.D., Westerman C.J., Gower C.F., Stone D., Desnoyers D.W., McWilliams G.H., Harris N., Findlay D.C.

Publisher Name: Ontario Geological Survey

Location:

Publication - NI 43-101 Technical Report on the Preliminary Economic Assessment of Lithium Hydroxide Production, Separation Rapids Lithium Project, Kenora, Ontario

Publication Number: 2016 43-101 Date: 2018

Author: Aiken, S.R., Gowans, R., Hawton, K.E, Jacobs, C., Ing, E., Pilcher, B.

Publisher Name: Micon for Avalon Advanced Materials

Location: SEDAR

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For detailed information regarding this mineral record please contact the Kenora Resident Geologist District Office