The Pilgangoora pegmatite deposit is one of the largest hard rock lithium deposits in the world. The prospective Pilgangoora pegmatites are located within the East Strelley greenstone belt, approximately 30km east of Wodgina.

The pegmatites strike sub-parallel to the dominant north-northwest trending fabric of the greenstone belt. Three principal pegmatite groups or domains are identified in the centre of the project area: Eastern, Central and South. Two outlying pegmatite groups, Monster and Southern, are also identified, which have strike lengths of up to 350m and 500m respectively. Pegmatites of the principal domains have a strike length of up to 1.4km, and mostly range in thickness from 1-30m, although pegmatites in the Central domain may be up to 70m thick. The pegmatite domains have variable dips ranging from shallow to sub-vertical to the east.

The pegmatite domains at Pilgangoora are composites of several intrusive phases emplaced sequentially over the duration of the late-stage Turner River orogeny. Lithium grade in the pegmatite domains is subject to two main influences, one primary and the other secondary. The primary ore types comprise mainly coarse spodumene, K-feldspar and quartz, and the abundance of spodumene relative to the other two gangue phases is likely the main control on grade variations in zones grading better than 2% Li2O.

The main modelled mineralized domains have a total dimension of 5,800m (north-south), ranging bet ........

The mining method used on site and proposed for future operations at 6.3 Mtpa is selective open pit excavation using drill and blast on 5.0 m high benches and load and haul on 2.5 m lifts. Hydraulic excavators (150-t) loading into 90-t rear dump haul trucks are used to separate waste rock (basalt and ultramafic) from mineralized pegmatite to minimize mining dilution. Ore contaminated with basalt is stockpiled for later processing through the ore sorting facility. Drilling uses track-mounted rigs, with sufficient mobility to access the pit from surface contour to pit bottom. The mining method is considered appropriate for the deposit geometry and production rates and has been in use since 2018. Access is easily available to all designed pits, waste dumps and stockpiles. A minimum mining width for pushbacks of 40m has been considered.

For the Central / Eastern deposit using 55°batters in the weathered domain and 75°batters in the transitional and fresh rock domains. Benches will be established every 20 m maximum with a minimum berm width of 10 m.

For the Monster deposit the weathered rock batter is 55° and the fresh rock better angle is 70°. Benches will be established every 20 m maximum with a minimum berm width of 10 m.

For the Lynas Find deposit, the weathered rock batter is 45° and the fresh rock better angle is 65°. Benches will be established every 20 m maximum with a minimum berm width of 15 m.

For South deposit, the weathered ........

Crushing and Ore Sorting (P680 Project)
The Crushing and Ore Sorting facility will replace existing contracted crushing services (over time) and is expected to lower operating costs, while also providing increased crushing capacity (5mtpa) to satisfy future expansion plans for the P1000 Project.

The Ore Sorting circuit has been configured to reject waste basalt and the primary ore gangue minerals (quartz and feldspar) through a combination of single pass optical and Xray ore sorting technologies. This will further support the Pilgangoora Ore Reserve for LOM processing of pegmatite ore, including any accumulated contaminated ore stocks.

Ore sorting technology will also support a reduction in mining volumes compared to historical rates. To date, ore material on the contact zone with elevated levels of basalt has been stockpiled for future processing.

On commencement of Primary Rejection commissioning, the Pilgan Plant’s annualised feed rate will increase to ~3Mtpa, exceeding the capacity of the existing contracted crushing facility. During the period when the new Crushing and Ore Sorting facility is being installed, additional contracted mobile crushing capacity will be utilised to accommodate increased Pilgan Plant feed rates.

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