The 3600-2800Ma North Pilbara basement terrane consists of a series of ovoid multiphase granitoidgneiss domes bordered by sinuous synformal to monoclinal greenstone belts.

The Wodgina Greenstone Belt is a north to northeast plunging synclinal structure 25km long and 5km wide, preserved as a roof pendant separating the Yule and Carlindi granitoid complexes. It is composed principally of interlayered mafic and ultramafic schists and amphibolite, with subordinate komatiite, clastic sediments, BIF and chert. The komatiitic and metasedimentary units within the Wodgina area are tentatively correlated to the Kunagunarrina and Leilira Formations respectively.

Archean volcanic activity and sedimentation was followed by the intrusion of Archean granitic batholiths with consequent deformation and metamorphism of the sequence. Late stage granitic intrusions resulted in the emplacement of simple and complex pegmatite sills and barren quartz veins.

The Wodgina pegmatite district contains a number of prospective pegmatite groups, including the Wodgina Deposit.

The Wodgina lithium mineralisation is hosted within a number of sub-parallel, sub-horizontal, northeast trending pegmatite intrusive bodies which base of the massive pegmatite apparently with a dip at between 5° to 30° to the west-southwest.

At this time individual pegmatites vary in strike length from approximately 200m to 400m. The thinner near surface pegmatites vary from 10m to 30m in thickness, but vary locally from less than 2m to up to 35m thick. The massive basal pegmatite varies from 120m to 200m thick. The pegmatites intrude the mafic volcanic and metasedimentary host rocks of the surrounding greenstone belt.

The lithium in the Cassiterite Pit and shallower pegmatites occurs as 10 - 30 cm long grey-white spodumene crystals within medium grained pegmatites comprising primarily of quartz, feldspar, spodumene and muscovite. Typically the spodumene crystals are oriented orthogonal to the pegmatite contacts. Some zoning of the pegmatites parallel to the contacts is observed, with higher concentrations of spodumene occurring close to the upper contact. In the massive basal pegmatite, the spodumene is distributed within fine-grained quartz, feldspar, spodumene and muscovite matrix.

A total of 40 separate pegmatite lenses have been interpreted. Individually they extend over strike lengths of between 100m and 1000m; with a project strike extending over 1.4km. Cross strike extents range from 50 to 300m for individual lenses, with vertical thicknesses of the lenses ranging from 5 to 50m.

The pegmatite lenses have been interpreted to a maximum depth of 300m below the surface.

The Li2O area of the resource consists of two main areas of the Cassiterite deposit, respectively 200m x 300m and 100m x 200m.

Mining is assumed to be by conventional open pit.

The mining operation extracts tantalum bearing pegmatite ores from the Mount Cassiterite and Tinstone open pits.

The first mining drill and blast operation to deliver high grade lithium DSO occurred on 6 March 2017 with the world’s first shipment of lithium DSO departing Port Hedland on 17 April with 114,000 wet tonnes on board bound for China.

Two mobile crushing plants were installed and commissioned in March 2017 producing the first 100,000 wet tonnes of lithium DSO.

Atlas Iron’s mining and crushing operations ceased at the Wodgina site in April, making available core processing infrastructure to MRL Group for the processing of lithium DSO and allowing a ramp-up in production and exports.