Albemarle will acquire a 50pc stake in the Wodgina project in western Australian for $1.15bn to produce spodumene concentrate and battery-grade lithium hydroxide.
The agreement was outlined in an exclusivity agreement from late November.
Albemarle will split ownership with Mineral Resources on the mineral rights, the spodumene plant and fixed infrastructure, utility assets and mobile mining equipment, and take no ownership in the iron ore and tantalum rights and the crusher.
Wodgina is expected to produce up to 100,000 t/yr of lithium carbonate equivalent, which will be used as feedstock for the future lithium hydroxide plant.
Both parties plan to fund, design, build and operate the plant constructed at Wodgina in two stages, drawing on Albemarle's core design.
Wodgina has the world's largest hard rock lithium resource at 259mn t grading 1.2pc lithium oxide and has until recently been the largest exporter of direct shipping lithium ore. It is now developing three spodumene concentrate trains that will each have capacity for 250,000 t/yr. The first train will be commissioned in early 2019, followed by the two others later in the year, taking total output to 750,000 t/yr by 2020.