The Cadillac Project reveals high-grade lithium at depth, combined with a vast region of unexplored pegmatites.
ASX-listed Olympio Metals Ltd (ASX:OLY) (Olympio) has secured the large Cadillac Lithium Project, which contains the advanced Wells-Lacourcière drill prospect, in Quebec, Canada. The vendor of the project, Vision Lithium (Vision), completed first-pass drilling during 2022, recording high-grade lithium of around 3.14% Li2O in hole CAD-22-04A and observed spodumene crystals in drill core.
The Cadillac Project is located in the centre of the Abitibi Lithium Hub, as defined by Sayona Mining Ltd (Sayona), operator of North American Lithium (NAL), the only operating lithium mine in Canada (Fig. 1).
The Cadillac Project is also proximal to several of the largest lithium resources in Canada, including Authier and Tansim, as well as major lithium projects like the Winsome Resources Ltd (ASX:WR1) Decelles Project. Quebec is a Tier 1 mining jurisdiction, ranking eighth in the world for mining investment attractiveness.
The project is logistically very favourably located on an all-weather road 50km west of major mining center Val-d’Or, which permits easy access for contractors and year-round exploration and drilling.
Wells-Lacourcière high-grade lithium prospect
Previous exploration by Vision has demonstrated the potential for the Cadillac Project to be highly prospective for bulk-tonnage spodumene mineralisation (Fig. 2).
Channel samples taken from exposed pegmatite dykes during late-2021 returned grades of up to 2.17% Li2O over 5.5m (Channel R7).
Diamond drilling during April 2022 confirmed down-dip extension of the mineralised pegmatite, with intersection of several high-grade zones:
1.00m @ 3.14 Li2O from 31m (CAD-22-04A)
1.90m @ 1.74 Li2O from 46m (CAD-22-07)
3.14m @ 1.31 Li2O from 142m (CAD-22-07)
6.40m @ 1.00 Li2O from 152m (CAD-22-13)
1.00m @ 2.73 Li2O from 29m (CAD-22-23)
2.00m @ 2.00 Li2O from 37m (CAD-22-25)
3.00m @ 2.13 Li2O from 1m (CAD-22-34)
Under-explored region with demonstrated large pegmatites
The Cadillac Project is large-scale, comprising of some 334 contiguous mining claims covering a surface area of 190km2. The project contains many pegmatites beyond the Wells-Lacourcière Prospect, both observed and interpreted, that are yet to be sampled (Fig. 3).
Recent exploration by Olympio defined a large and highly prospective pegmatite, Dyke Z (1.3km long x 150m wide), which was previously undiscovered, within 2.5km of the Wells-Lacourcière prospect.
Detailed interrogation of LiDAR-derived digital elevation model (DEM) data reveals the potential for discovering numerous other large pegmatites through further exploration by Olympio during 2024. Interpretation of LIDAR-DEM data by consultants Geomantia has revealed some 400 pegmatites within the project area and recent ground-truthing by Olympio suggests this may be a conservative estimate.
A rock-chip geochemistry programme conducted by Vision in the southern portion of the project in 2022 identified a large but discrete region of pegmatites with highly favourable geochemistry for lithium mineralisation (K/Rb <30) (Fig. 3).
The region immediately beyond the Wells-Lacourcière Prospect remains largely un-explored for lithium, despite numerous pegmatites having been interpreted.
Targeting large pegmatites with demonstrated lithium fertility
Olympio commenced fieldwork at the Cadillac Project in 2023, using portable Laser-induced Breakdown Spectroscopy (LIBS) and X-ray Flourescence (XRF) analysers to speed up the exploration, particularly in the unexplored region surrounding the high-grade lithium occurrences at Wells-Lacourcière.
These portable analysers can determine geochemical ratios of pegmatite minerals, which indicate how evolved the pegmatites are and what the likelihood of lithium fertility is. These pathfinders have been used to define lithium-bearing pegmatites with great success, globally.
Recent mapping and sampling by Olympio have identified the very large pegmatite Dyke Z, which is 1.3km long and up to 150m wide, providing scale for potentially significant discovery. The Dyke M zone, located 1.5km south-east of the Wells-Lacourcière spodumene-bearing dykes, also contains pegmatites of significant size, up to 400m long and up to 70m wide (Fig. 4).
Drilling planned for early-2024
Drilling permit applications have been submitted and diamond drilling is anticipated to commence in January 2024. This drilling campaign will cover the Wells-Lacourcière Prospect, Dyke Z, Dyke M, and several other pegmatites, which have delivered encouraging XRF pathfinder analyses.
Post-drilling, Olympio is looking forward to Spring 2024, when we can resume exploring the significant number of large pegmatites with potential for lithium fertility, which remain to be discovered in the project area.
Please note, this article will also appear in the seventeenth edition of our quarterly publication.
