Mt Marion Lithium Expansion Advances as MinRes and Ganfeng Lift Spodumene Supply

Mineral Resources

Mt Marion lithium expansion is moving ahead after Mineral Resources and Jiangxi Ganfeng Lithium reached a final investment decision on a A$490mn upgrade at the Western Australian mine. The project will raise 6% spodumene concentrate output from 500,000 t/yr to 600,000 t/yr.

Mt Marion lithium expansion reflects renewed confidence in spodumene markets after a period of stronger pricing, Chinese demand and supply disruption from Zimbabwean export controls. The decision also reinforces Australia’s role as a core lithium feedstock supplier to global battery material chains.

Mt Marion lithium expansion includes A$220mn for underground mine development, A$240mn for a flotation plant and A$30mn for non-processing infrastructure. Construction is scheduled to begin in July-September.

The partners expect to commission the mine within 12 months of construction starting, with production ramp-up over the following six months. That timeline makes Mt Marion an important near-term growth project in the Australian hard-rock lithium sector.

Underground Mining Extends Mine Life and Feed Flexibility

The underground mine will supplement ore from the existing open pit and contribute up to 40% of processing feed. This will extend Mt Marion’s remaining mine life by six years beyond the previous estimate of 10 years.

That is strategically important because mine life extension improves supply visibility for customers and investors. Battery chemical producers need stable spodumene feedstock to support long-term lithium hydroxide and lithium carbonate production.

The underground development also gives MinRes and Ganfeng more operational flexibility. Combining open-pit and underground ore can support feed blending, grade control and continuity as the mine matures.

The project will cause minimal disruption to existing operations, according to the company. That matters because the mine is already a major producing asset and any downtime could affect near-term shipments.

Mt Marion is also backed by a strong downstream partner. Ganfeng is one of China’s leading lithium companies, giving the project a direct link to one of the world’s largest battery materials markets.

Flotation Plant Targets Higher-Grade Product Mix

The new flotation plant will remove SC3.5 product from MinRes’ mix and deliver a minimum SC5 grade product. This is a key upgrade because higher-grade concentrate can improve processing efficiency for downstream converters.

SC6 remains the benchmark product for hard-rock lithium supply. Increasing SC6 output to 600,000 t/yr gives Mt Marion stronger exposure to higher-value concentrate markets.

The investment economics are highly sensitive to price. At an assumed SC6 price of $2,700/t, MinRes expects the expansion payback period to be less than one year.

Spodumene prices have risen in recent months, supported by Zimbabwe’s lithium concentrate export controls and strong Chinese demand. The latest Australian SC6 assessment was $2,661/t on 19 May, down from $2,811/t a week earlier but still elevated enough to support renewed investment.

MinRes also cited higher lithium prices as a reason for restarting operations at its Bald Hill mine in Western Australia. Together, these moves suggest producers are again positioning for stronger lithium feedstock demand.

The broader lithium market remains volatile, but the Mt Marion decision shows that high-quality Australian assets can still attract capital when pricing, partners and mine-life extension align.

The Metalnomist Commentary

Mt Marion’s expansion shows that lithium investment is returning first to established, scalable assets with strong downstream links. The key lesson is that the next lithium cycle will reward producers that can improve grade, extend mine life and secure reliable routes into China’s battery supply chain.