The Greenbushes pegmatite deposit consists of a primary pegmatite intrusion with numerous smaller, generally linear pegmatite dikes and pods to the east. The primary intrusion and its subsidiary dikes and pods are concentrated within shear zones on the boundaries of granofels, ultramafic schists and amphibolites. The pegmatites are crosscut by ferrous-rich, mafic dolerite which is of paramount importance to the current mining methods. The pegmatite body is over 3 km long (north by northwest), up to 300 m wide (normal to dip), strikes north to north-west and dips moderately to steeply west to south-west. The syn-tectonic development of the pegmatite has given rise to mylonitic fabrics, particularly along host rock contacts.

The Greenbushes pegmatite is mineralogically segregated into five primary zones. Internally, the Greenbushes pegmatite consists of the Contact Zone, Potassium Feldspar (Potassium) Zone, Albite (Sodium) Zone, Mixed Zone and Spodumene (Lithium) Zone. The zones differ from many other rare-metal pegmatites in that they do not appear concentric, but are lenticular in nature, with inter-fingering along strike and down dip. They do not have a quartz core. The mine sequence was later subjected to the transgressive east-west dike and conformable sill dolerite intrusions.

The highest concentrations of primary ore minerals are found in specific mineralogical zones or assemblages within the pegmatite. The high-grade lodes within the main pegmatite ........

Current mining at Greenbushes is based on open pit extraction using conventional hydraulic excavators and haul trucks; mining is at a rate of approximately 4.5 million bank cubic meters per annum (“Mbcmpa”). The mining activities of load and haul are carried out by mining contractor, SG Mining Pty Ltd (“SGM”), and drill and blast activities are contracted to Action Drill and Blast Pty Ltd (“ADB”); Talison provides grade control and overall pit management.

Historically there was underground and open pit mining at Greenbushes, but the mineral reserves and LoM plan are based only on open pit mining.

Open cut mining of lithium ore is currently from the Central Lode open pits, south of the Cornwall Pit. The higher grade lithium ore is mined from a distinct zone within the pegmatite on the hanging wall side of the C3 (North) zone and from the large zone within the C1 (South) zone.

The mining plan involves a series of stages, including eastern and western cutbacks of the C1 and C3 pits. The eastern cutback of C3 pit, which has commenced, is in two parts, Central and East, with the Central cutback of the east wall being taken down initially before moving to the southern wall and taking out the saddle between the C3 and C1 pits, within the area referred to as the C2 pit. During the 21-year period scheduled, the overall Central pit will have a number of staged cutbacks involving both the east and west walls as well as the mining of the Kapanga pit to ........

- subscription is required.

- subscription is required.