Overview

Deposit type

• Pegmatite

Summary:

The deposit is a pegmatite hosted spodumene lithium deposit. The pegmatites are hosted entirely within granitic rocks.

The Project is located within broadly north-south trending belts of Birimian (Paleoproterozoic) metavolcanic and metasedimentary rocks which are intruded by syn- and post-orogenic granitoids which host an array of spodumene bearing pegmatite dykes and sills. Outcrop is limited and geology is interpreted from mapping, drilling, and geophysics. Northeast striking metapelite and metagreywacke rocks in the north and east of the property are intruded by granodiorites and pegmatite dykes and sills in the south. Regolith is up to 10 metres thick and comprises a surficial transported gravel horizon overlying a thin laterite weathering profile. Weathering varies from less than a metre to up to 70 metres depth.

The Goulamina deposit consists of a swarm of sub-parallel spodumene bearing pegmatite dykes which intrude the granodiorite. They strike NE-NNE, dip between 50 and 70 degrees to the east, are between 1 and 2 kilometres in length and between 5 metres and 100 metres thick. From east to west the major pegmatite dykes are named; Main, West, Sangar I, Sangar II and Danaya. At Danaya, the pegmatites are variously oriented.

Pegmatite contains between 0.5% and 25% of the lithium bearing pyroxene mineral spodumene, resulting in grades between 0.1% Li2O and 6% Li2O. The major minerals are quartz and feldspar (albite and microcline) with minor muscovite. The pegmatites are comprised of both coarse-grained pegmatite (up to >10cm spodumene blades) and white fine-grained (<1mm) aplite or albitite. The logged ratio of coarse grained to fine-grained material is about 3:1. Albitite contains only minor spodumene.

The Goulamina Mineral Resource has an overall strike extent of 2.9km N-S, and 1.5km E-W. Mineralisation is exposed at surface in the central portion of the Main Zone. The remaining mineralisation domains are buried below laterite and weathered saprolite, and saprock. Weathering and laterisation processes have removed most of the Li2O from the pegmatites between the surface and the base of oxidation (BOCO). No resources have been defined in the weathered part of the resource as this clay rich material is deleterious to the process and cannot be economically beneficiated.

The deepest drilling extends to 230m below surface and the deepest known mineralisation is at 220m below surface. The Inferred Mineral Resource extends to 300m below surface. The interpreted mineralisation has not been closed off at depth, although in a few areas, deep watercourses appear to have preferentially eroded spodumene (and Li2O ) from the pegmatite host.

Mineralised zones in the north-eastern domains are interpreted to dip moderately to the northeast. Drilling is generally oriented - 60 degrees due west. Intersection angles on the mineralised zone are between 35 and 65 degrees depending on the local strike of themineralised pegmatite. True widths of mineralisation are between about 75% and 40% of downhole widths.

Mineralised zones in the Danaya resource area are hosted within intersecting dykes and sills that are shown to be variously oriented.

Mining Methods

• Truck & Shovel / Loader

Summary:

A standard open-pit mining operation of drill, blast, excavation, and truck haulage will be employed for the Project. Contractors will be employed for mining operations. Given the nature of the deposit, the pegmatites will be mined from footwall to hanging wall, rather than selectively using a cutoff grade, hence a zero cut-off grade applies.

The shape and geometry of the final and internal designs allowed the main pit to be mined in four successive stages A starter pit will be developed on each of the Main and Sangar domains followed by a cutback to fully exploit Sangar and then a further cutback of the sangar pit to exploit the Main and West domains. A satellite pit at Danaya forms an independent fifth stage.

Mining will create flat, 5 metre height working benches to allow geological mapping and grade control via RC and blast hole drilling. Where possible, waste will be blasted separately from ore. Blasting primarily 5 metre bench heights using bulk emulsion explosives and non-electric initiation. There will be some bulk waste areas where higher 10 metre benches will be employed.

Excavation of the ore and waste will be undertaken with 2 x 120 – 150 tonne excavators. Haulage of ore and waste will be undertaken using up to 10 x 90 tonne dump trucks operating on two-way haul roads with a maximum gradient of 10%. The ore will be hauled to the ROM pad and tipped onto finger stockpiles of low, medium, and high-grade ore. A front-end loader will feed a blend of ore into the primary crusher to keep the feed grade consistent with the mine production schedule, which seeks to optimise bothrecovery and concentrate grade.

Open pit wall slope angles were based on a geotechnical assessment. A ramp width of 25m based on the selected truck size. The resulting overall slope angles on the final pit approximate 46° in fresh rock and 36° in weathered material, depending on ramp location.

A review of equipment selection and pit designs for the original Definitive Feasibility Study (DFS) has determined that there are no mining constraints to increasing throughput to 4.0 million tonnes per annum.

Comminution

Crushers and Mills

Summary:

The revised process flowsheet will comprise the following unit processes:
• Three-stage crushing to a P80 of 6.2 millimetres with a fine ore bin and overflow dead stockpile;
• Closed circuit ball milling and screening to an estimated P80 of 180 µm based on a closing screen P100 of 212 µm.

Due to the difficulty in changing out, or adding jaw crushing capacity once in production, the design and cost estimate is based on installing a large single jaw crusher in Stage 1 that can accommodate 4.0 million tonnes per annum throughput.

The surge bin above the secondary cone crusher will be designed to feed two units, although Stage 1 (2.3 million tonnes per annum) only requires one. This will allow a second feeder and cone crusher to be installed as part of Stage 2 (4.0 million tonnes per annum) without a lengthy shutdown required. The concrete and steelwork in the secondary & tertiary crushing building has been designed and will be installed as part of Stage 1 to allow for Stage 2 equipment.

The conveying layout from the fine ore storage to the milling circuit includes a splitter bin before milling rather than conveying direct from the bin to the mill feed. This feature enables a future feeder and conveyor to be installed to feed the second mill train without a major shutdown and capitalintensive project to modify the mill feed.

Processing

• Crush & Screen plant
• Wet Screening
• Desliming
• Dry Screening
• Flotation
• Magnetic separation
• Dewatering

Summary:

The revised process flowsheet will comprise the following unit processes:
• Two-stage magnetic separation;
• Three stage flotation (roughing, cleaning and recleaning);
• Concentrate dewatering, filtration and storage;
• Separate flotation and process tailings thickening with common tailings pumping to a Tailings Storage Facility;
• Reagent mixing and distribution;
• Separate flotation and process water circuits;
• Air services.

The DFS Update envisages building a 2.3 million tonne per annum throughput plant accommodating in the design the infrastructure and equipment to accommodate the construction of a Stage 2 expansion to increase plant throughput to 4.0 million tonnes per annum. The expansion of the plant will be built after commissioning of Stage 1 and be commissioned approximately 18 months after commissioning. The staged approach allows the process flow sheet to be optimised for full production based on operating experience.

The surge bin above the secondary cone crusher will be designed to feed two units, although Stage 1 (2.3 million tonnes per annum) only requires one. This will allow a second feeder and cone crusher to be installed as part of Stage 2 (4.0 million tonnes per annum) without a lengthy shutdown required. The concrete and steelwork in the secondary & tertiary crushing building has been designed and will be installed as part of Stage 1 to allow for Stage 2 equipment.

The conveying layout from the fine ore storage to the milling circuit includes a splitter bin before milling rather than conveying direct from the bin to the mill feed. This feature enables a future feeder and conveyor to be installed to feed the second mill train without a major shutdown and capitalintensive project to modify the mill feed.

The plant layout has been designed with a central services spine of structural steel supports, to accommodate the installation of Stage 1 and Stage 2 pipework, electrical, controls and instrumentation infrastructure and enable a linear flow of process plant infrastructure. This design enables Stage 2 infrastructure and services to be mirrored on the opposite side to the Stage 1 equivalents for the milling, magnetic separation, and flotation areas with minimal impact on operations.

The Stage 2 milling and classification plant will replicate the Stage 1 plant unless operations highlight that changes are required to grind size. This will provide valuable operational redundancy and commonality to the operation.

When Stage 2 is completed, the two-train milling and processing circuit will have increased operational flexibility enabling a 2.3 million tonne per annum throughput rate to continue during milling circuit maintenance outages.

Production

Operational metrics

Personnel

Job Title	Name	Profile	Ref. Date
Chief Operating Officer	Tim Richards		Jan 10, 2024
Environmental Manager	Amadou Diadie Makalou		Feb 16, 2024
General Manager	Seydou Semega		Jan 10, 2024
General Manager Operations	Mohamed Sid'Ahmed		Jun 11, 2024
Managing Director	Simon Hay		Jan 10, 2024
Safety Manager	Toutou Dabo		Jan 10, 2024