Summary
Beyond Lithium has three projects in the Georgia Lake District: Cosgrave Lake (8,993 ha), Gathering Lake (6,948 ha), and Arrel Lake (3,585 ha). This district is an active and prolific lithium exploration area including Imagine Lithium’s (TSX-V: ILI)1 Jackpot Lithium Project which has a historical lithium resource in the Main zone, Rock Tech Lithium’s (TSX-V: RCK) Georgia Lake Project which has published a lithium pre-feasibility study in 2022, Balkan Mining’s (ASX: BMM) flagship Gorge Lithium Project. Beyond Lithium at the Cosgrave Lake Project:
- Discovered a brand-new fertile lithium-cesium-tantalum (“LCT”) pluton, the Allen Graeme (“AG”) Pluton, which has a similar size to the other plutons in the Georgia Lake District and a comparable chemistry background to the source and the pluton of the Tanco lithium mine located at Bernie Lake, Manitoba.
- Established a mineral and fractionation zonation around the AG Pluton comparable to the MNW spodumene-bearing pegmatite’s mineral zonation located 2.8km north of the Cosgrave Lake Project.
- A grab sample returned with 0.39% Li2O (1,832ppm Li) and 2.77% Manganese (Mn) indicating the proximity to the potential discovery of a higher-grade lithium spodumene zone.
Latest News Releases
- November 20, 2023 – Beyond Lithium Establishes Zonation at Cosgrave Lake Project Indicating Proximity to Potential Spodumene Zone
Infrastructure
The Cosgrave Lake Project can be accessed via the Trans-Canada Highway and a network of well-maintained logging roads. The Project is less than 20km north of the town of Nipigon, and about 100km to the northeast of Thunder Bay. The Project also has excellent nearby infrastructure including ports, powerline, local labor force and equipment, and communications.
Regional Context
The Georgia Lake District that has several well-known fertile plutons namely the MNW pluton, the Barbara Lake pluton, and the Pine Portage pluton and their associated lithium-bearing pegmatite groups with more than 28 lithium occurrences recorded by Ontario Geological Survey. These well-established fertile plutons in the Georgia Lake district are associated as the source of several prolific lithium pegmatite belts including the Imagine Lithium MNW, as well as the Georgia Lake belts and Rock Tech lithium belts.
Map of Beyond Lithium Projects, Cosgrave Lake, Gathering Lake (E,W,S), and Arrel Lake in the Georgia Lake District and Nearby Projects
Allen Graeme (“AG”) Pluton Discovery
Beyond Lithium’s team discovered a brand-new fertile pluton named as the AG Pluton at the Cosgrave Lake Project. The AG Pluton covers an area of over 266 hectares, which is comparable in size to the MNW pluton (351 ha) and the Pine Portage pluton (311 ha). The analogous size of the AG Pluton to other fertile plutons strongly suggests that the AG Pluton has generated substantial amounts of concentrated fluids and volatiles, serving as the source of lithium and rare earth minerals in lithium pegmatite formations in the vicinity.
Map of AG Pluton and its Associated Pegmatite Zone in Relation to Other Fertile Plutons and their Associated Pegmatite Groups
Mineral Zonation & Fractionation Trend
After the discovery of the AG Pluton, Beyond Lithium advanced the exploration at the Cosgrave Lake Project and focused on the detailed and systematic mapping and sampling of the property starting from the core of the AG pluton and moving outwards. This advanced exploration program successfully delineated a mineral zonation and fractionation trend for lithium mineralization at the project; the mineral zonation at the Cosgrave Lake Project is comparable with the mineral zonation of the MNW lithium occurrence with up to 5.82% Li2O associated with the MNW stock located 2.8km north of Cosgrave Lake Project.
Cosgrave Lake Project Delineated Mineral Zonation around the AG Pluton transitioning from a pegmatitic textural border zone to a beryl zone and to a green muscovite zone
Samples collected from the Cosgrave Lake were plotted up in a log(K/Cs) ratio vs log(K/Rb) graph in order to establish the systemt’s fractionation trend. Measuring the ratio variations between potassium (“K”), cesium (“Cs”), rubidium (“Rb”) in samples is a common and useful exploration tool to display the fractionation trend or the relative degree of evolution of S-type, peraluminous granites and related pegmatite granites and the rare-element pegmatite groups that fractionated from the parent granitic rocks. Three zones of fractionation were outlined from the graph as the high (“H”), moderate (“M”), and low (“L”). The three fractionation zones coincide with the established mineral zonation where the border zone correlates with the low fractionation zone, the beryl zone correlates with the low to moderate fractionation zones, and the green muscovite zone correlates with the moderate to high fractionation zones. This strong correlation between the fractionation trend and the mineral zonation at Cosgrave Lake supports the fertility of the AG Pluton that it has high concentration of lithium volatiles to fractionate and continues to vector the exploration trend towards the northeast orientation.
Map of High, Moderate, Low Fractionation Zonation from the Plot of Log(K/Cs) vs (K/Rb) Coincides with Mineral Zonation
Exploration
The 2023 exploration program established a mineral zonation and a fractionation trend at Cosgrave Lake in which vectored the primary exploration area along the main NE and SW oriented corridor that spans 11 km of prospective ground around the AG Pluton and along the regional subprovince boundary. Beyond Lithium will continue to focus on exploring the potential proximal spodumene-bearing zone at the Cosgrave Lake Project around the 0.39% Li2O pegmatite sample and, in unison, will follow up on the newly established northeast zone with moderate fractionated samples that sits 6.5km northeast of the AG pluton and similarly towards the southwest part of the AG pluton in the next field program.
Field Crew Inspecting the First Beryl-Bearing Pegmatite Identified at Cosgrave Lake