Adina Lithium Project — 2024 Technical Report

This report details the proposed repurposing of the existing Renard diamond processing plant for spodumene concentrate production from the Adina lithium deposit.

Report context

This technical report, dated September 30, 2024, presents a Preliminary Economic Assessment and Mineral Resource Estimate for the Adina Lithium Project. The report describes the planned processing route whereby mineralized material from the Adina site would be mined and transported approximately 60 km south to the existing Renard process plant, which has been in care and maintenance since October 2023. The Renard facility, originally built for diamond recovery from kimberlite, would be modified to treat spodumene-bearing pegmatite at a design throughput of 1.70 Mt per year.

Processing route

Proposed Design Overview

Winsome plans to treat run-of-mine material grading 1.24% Li₂O (average life-of-mine feed grade) through a crushing and dense media separation (DMS) flowsheet. The modified process plant targets an average production of 255,900 tonnes per year of SC5.5 spodumene concentrate. The proposed design includes three-stage crushing, two-stage particle mineralized material sorting, two-stage DMS, concentrate cleaning by magnetic separation and upflow classification, and processed pegmatite dewatering and handling.

Existing Renard Diamond Processing Plant

The existing Renard plant, constructed from July 2014 with commercial production beginning in late 2016, had an initial design capacity of 2.16 Mt/y at 78% utilization (equivalent to 6,000 t/d). Plant capacity was later increased to roughly 7,000 t/d through equipment optimization and maintenance sequence improvements. The facility comprises a single line of comminution and mineralized material preparation housed within heated buildings, transfer towers, and conveyor galleries.

The original diamond recovery circuit consists of a three-stage crushing circuit (jaw crusher, cone crusher, and high-pressure grinding rolls), an integrated drum scrubber, a particle mineralized material sorting plant (placed into care and maintenance in 2020 and never restarted), two parallel DMS circuits, and a large diamond recovery circuit. The design philosophy aimed to recover the coarsest diamonds possible, with recirculating loads to recover diamonds as they became liberated.

Proposed Modifications for Spodumene Processing

Most existing equipment will be re-used for pegmatite processing. The scrubber will be removed and replaced with a conveyor and wash chute. A new rock breaker will be installed, and the secondary cone crusher replaced with a larger unit (HP500 or equivalent). The high-pressure grinding rolls will be replaced with a cone crusher (MP800 or equivalent) to reduce fines generation and associated lithium losses. The large diamond recovery circuit will be by-passed.

The former diamond recovery secure area (Red zone) will be de-constructed to house a new secondary DMS circuit and concentrate cleaning area. A second-stage modular DMS circuit with feed bin will be installed, along with magnetic separation (three wet double drum high-intensity magnetic separators operating in parallel) and an upflow classifier (fluidized bed separator) for mica removal.

Modifications to the Sorting Circuit

The particle mineralized material sorting circuit comprises two coarse sorters in rougher and scavenger arrangement for +65 mm material and four fine sorters (three rougher, one scavenger) for -65 mm +20 mm material. In early years, low levels of host rock dilution are anticipated and sorting will be by-passed. The sorting circuit will be commissioned at year 6 of life-of-mine when higher dilution is expected. A third secondary sorter is planned for installation at year 2 as a contingency.

Proposed Crushing and DMS Circuit

ROM material is trucked to a 170 kt capacity storage facility at Renard and fed to the primary jaw crusher via apron feeder and vibrating grizzly feeder. Primary crushed product (approximately 80% passing 110 mm) feeds a 750 tonne bin. Material is screened, with -1 mm fines directed to a degrit circuit, -20 mm +1 mm sent to cone crushers, and +20 mm material directed to the sorter circuit or secondary cone crushers.

The secondary cone crusher (fed from an 80 tonne bin) crushes to 100% passing 45 mm. A double-deck screen recirculates +32 mm material to either the sorting plant or secondary crusher feed. The -32 mm +1 mm material is fed to a cone product screen which sends -8 mm +1 mm material (target crush size) to the DMS circuit feed bin. The -32 mm +8 mm material goes to a 150 tonne bin feeding a tertiary cone crusher, crushing to 100% passing 25 mm, with product recirculated to the initial double-deck screen.

The DMS circuit comprises two primary circuits (each with four 410 mm diameter cyclones) and one secondary circuit (one 610 mm diameter cyclone). The -8 mm +1 mm fraction is collected in a 240 tonne DMS feed bin with two independent outlets. Primary DMS floats are sent to processed pegmatite disposal and primary DMS sinks (higher density material) proceed to the secondary DMS circuit, operated at a higher density cut-point. Secondary DMS floats are sent to disposal and secondary DMS sinks (high density material) proceed to concentrate cleaning. Ferrosilicon suspended in water is used as the dense medium.

Concentrate Cleaning and Product Handling

The non-magnetic material from the three magnetic separators is dewatered and fed to an upflow classifier for mica particle removal. The classifier underflow is the final spodumene concentrate grading 5.5% Li₂O. Concentrate is conveyed to a 15,000 t storage facility.

Processed Pegmatite Handling

Fine material (-1.0 mm) from sizing screens is pumped to a degrit circuit with two stages of cyclone clusters in series and dewatering screens, splitting solids at approximately 0.3 mm. The -1.0 +0.3 mm material is combined with dewatered DMS circuit rejects before feeding a 500 tonne processed pegmatite bin for truck loading. The -0.3 mm overflow is transferred to a high-rate thickener (19.8 m diameter). Thickener overflow is recirculated as process water; underflow is pumped to Processed Pegmatite Containment 1 for the first 4 years. A filter press will be commissioned at year 5 for additional dewatering before trucking to Processed Pegmatite Containment 2.

Historical Operating Data

The Renard plant achieved an initial capacity of 6,000 t/d (2.16 Mt/y at 78% utilization) and was later increased to roughly 7,000 t/d through optimization. The plant has been in care and maintenance since October 2023.

Testwork Basis

Inputs for process design criteria and mass balance were based on analysis of test work results, industry benchmarking, process simulations, and assumptions based on experience and the nature of the mineralization.

Key reported parameters

Technical qualifications

The process design criteria and mass balance inputs were based on analysis of test work results, industry benchmarking, process simulations, and assumptions based on experience and the nature of the mineralization. Process plant modifications are required to the existing Renard diamond processing plant to treat spodumene-bearing pegmatite mineralized material. The report is a Preliminary Economic Assessment and Mineral Resource Estimate and does not constitute a feasibility study.

Source: Preliminary Economic Assessment & Mineral Resource Estimate for Adina Lithium Project – September 30, 2024, Section 17 Recovery Methods.