The Barroso – Alvão Region is characterized by the presence of a large field of several dozen pegmatite and aplite-pegmatite dykes of granitic composition. Pegmatite dykes are mainly intruded in the granitic rocks of the region whilst aplite-pegmatite dykes are hosted by low- to medium-grade metasedimentary rocks of Silurian age that are strongly deformed (B. CHAROY et al.,1992). The thickness of these dykes ranges from less than 1m up to 50m.

The Li-rich aplite-pegmatite dykes show a spatial distribution of 3 sub-types (LIMA et al, 2003):
- Spodumene-rich aplite-pegmatite dykes and sills are dominant at N and NE regions;
- Petalite-rich are dominant at SW; and
- Lepidolite-rich occur at NW regions.

The Mina do Barroso Project is centred on a series of spodumene rich aplite-pegmatite dykes and sills which have formed the basis of this study.

Grandao Deposit: Mineralised zone over 500m long, 450m wide and pegmatite depths of up to 50m. Results from recent drilling has recorded the broadest and most significant results for the Project to date.

Reservatorio Deposit: Drilling has confirmed that the lithium mineralisation extends to over 400m strike length, with good down dip extensions of at least 100m.

NOA Deposit: Drilling has confirmed the presence of lithium mineralisation over a 200m strike length together with good down dip extensions of at least 50m.

The Mina do Barroso project will have four surface workings/open pits: Grandao, Pinheiro, Reservatorio and NOA.

Mining Inventory
Conceptual open pit mine planning for the Mina Do Barroso Lithium Project was developed targeting an annual plant feed rate of 1.3Mtpa with an estimated average over the life of mine mill head grade of 1.02 %Li2O (diluted), with an average overall strip ratio of 5.2:1 (waste:ore ratio) and a resultant eleven plus year life of mine (LOM).

Three geological block models (one for each respective deposit) were provided and conceptual pit shells were generated using an optimisation software founded on the Lerchs Grossman algorithm.

The Mina do Barroso total site conceptual infrastructure stretches 5 km by 2.5 km over relatively steep and undulating terrain. All conceptual mine infrastructure and excavations developed in this study were restricted to:
- within tenement boundaries;
- minimised sterilisation of prospective target exploration zones;
- respected offset boundaries for major watercourses; and
- legacy travel routes (where available).

As the Project progresses further refinements to haul routing plans, waste rock storage management and pit staging should be targeted to take advantage of opportunities for reduced haulage capital and operating costs.

Quantities of bulk pegmatite are also included in the production plan as valuable material below the cut-off grade ........

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