The Finniss Lithium Project (Grants and BP33 Lithium Deposits) is hosted within a rare element pegmatite that is a member of the Bynoe Pegmatite Field. The Bynoe Pegmatite Field is situated 15km south of Darwin and extends for up to 70km in length and 15 km in width. Over 100 pegmatites are known within clustered groups or as single bodies. Individual pegmatites vary in size from a few metres wide and tens of metres long up to larger bodies tens of metres wide and hundreds of metres long.

The pegmatites are predominantly hosted within the early Proterozoic metasedimentary lithologies of the Burrell Creek Formation and are usually conformable to the regional schistosity. The Bynoe pegmatites are classified as LCT (Lithium-Caesium-Tantalum) type and are believed to have been derived from the ~ 1845 Ma S-Type Two Sisters Granite which outcrops to the west.

Fresh pegmatite is composed of coarse spodumene, quartz, albite, microcline and muscovite (in decreasing order of abundance). Spodumene, a lithium-bearing pyroxene (LiAl(SiO3)2), is the predominant lithium- bearing phase and displays a diagnostic red- pink UV fluorescence. The pegmatite is not strongly zoned, apart from a thin (1-2m) quartz-mica-albitewall facies and some barren internal quartz veins.

The geological interpretation is considered robust due to the nature of the mineralisation. The mineralisation is hosted within the pegmatite. The locations of the hangingwall and footwall of the pegmatite intrusion are well understood with drilling which penetrates both contacts.

The Finniss pegmatites have intruded early Proterozoic shales, siltstones and schists of the Burrell Creek Formation which lies on the northwest margin of the Pine Creek Geosyncline. To the south and west are the granitoid plutons and pegmatitic granite stocks of the Litchfield Complex. The source of the fluids that have formed the intruding pegmatites is generally accepted as being the Two Sisters Granite to the west of the belt, and which probably underlies the entire area at depths of 5-10 km.

The pegmatite is considered to be continuous over the length of the deposit. It thins and pinches out to the north and south. The mineralisation terminates approximately 40 m from the northern extent of the modelled pegmatite. A non-mineralised wall rock phase of 1-2m thickness is often present. A single grade domain has been identified and estimated using a hard boundary.

The lithium is hosted within a 170m long section of mineralised pegmatite which strikes NE and averages 20-30m in true width.

The pegmatite is sub-vertical to steeply east dipping and has been intersected at a depth of approximately 240m below surface.

Whilst continuous, the pegmatite body does appear to narrow to the north but remains open to the south. The pegmatite is deeply weathered to depths of approximately 50m below surface.

Contract mining services are proposed for the mining operation. Mining is expected to be straightforward conventional open pit mining utilising standard drill and blast and conventional excavator and truck fleet. There is very little groundwater and geotechnical conditions are not problematic.

Mining will be focused on delivering sustainable ore quantities to the ROM pad. Crushing and screening or processing of the delivered ROM ore will produce product ready for haulage to the Port of Darwin.

As a result of the test work conducted to date, the following flowsheet is proposed:
- Feed preparation by conventional tertiary crushing circuit followed by fines removal.
- Coarse spodumene concentrate generated by Dense Medium Separation (DMS) with middlings stream stockpiled for possible future recovery through other methods and throwaway tail.
- Because of the low mica content of the spodumene ore (<23%), the use of a reflux classifier has demonstrated limited mica removal benefit.
- Thickening of tailings for disposal.