The Earl Grey pegmatite is hosted within a series of steeply dipping ultramafic and mafic rocks of Archaean age. The pegmatite consists of a main tabular body of approximately 1,000m in strike length, over 2,000m in dip extent, and thicknesses of up to 100m. This main pegmatite is flanked by several hanging wall and footwall dykes, and the main body itself branches into multiple dykes at its southern and eastern extents. The pegmatite dips 5-15° to the north west and is slightly offset by several north-south trending fault zones.

The mineralogy of the pegmatite consists of a simple albite-quartz-microcline-spodumene-petalite assemblage with minor biotite, muscovite and tourmaline. The only significant mineralogical variation across the deposit occurs within the lithium aluminosilicates; spodumene, petalite and several alteration phases occur in discrete domains.

Spodumene is present in two forms at Earl Grey; a coarse form produced during initial crystallisation of the melt, and a finer spodumene-quartz intergrowth (SQI) derived from the isochemical inversion of petalite.

The Mount Holland Lithium Project (the project) is an integrated project consisting of a mine, concentrator, and refinery to produce battery quality lithium hydroxide (LiOH) for the international market.

Conventional open pit mining utilising experienced contractors will be adopted at Earl Grey(subject to further study). The mining method was evaluated for a traditional truck and hydraulic excavator (backhoe) operation, combined with suitable drill and blast. The operation evaluated different bench heights in different areas of the pit. In the pegmatite and waste contact zones, mining was determined to be standard 5m benches (2 x 2.5m flitches), and a 10m bench height was assumed for bulk waste mining outside of these zones. Ramp widths were maintained at a nominal 30m. A series of 15 pit designs (staged cutbacks) are planned with mining developing from the initial pits at the south end where the pegmatite comes to surface and proceeding in a northerly direction as the deposit is systematically mined down dip. Equipment (100t-200t excavators loading 100-200t trucks) has been selected and scheduled to meet the 2Mtpa plant throughput. Overall the pit design contained 94.2 million tonnes of ore at 1.5% Li2O and 421 million tonnes of waste at an overall strip ratio of 4.5 to 1.Dump trucks will haul ore to the ROM pad approximately 2km haul from the pit crest to the ROM. After various pit optimisations were performed using the geological block model which supports ........

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