Interview with Tiago Cunha, Director & CEO of South Star Battery Metals
Recording date: 11th September 2026
South Star Battery Metals Corp (TSXV:STS) is a rare example in the junior mining space of a genuine operational turnaround delivering measurable results within a single year. The company's Santa Cruz graphite operation in Bahia, Brazil came close to bankruptcy in October 2025, with insufficient funds to meet payroll. CEO Tiago Cunha, then a board member and investor, stepped in, personally funding two payroll cycles before a capital raise closed in December 2025. He describes replacing effectively the entire workforce and management team, citing prior contracting misconduct and kickbacks, and crediting the new operational team led by COO Rogério Barcellos with proving the underlying asset was never the constraint.
Since the turnaround began, management reports a 60% reduction in cash operating costs, driven by straightforward fixes: renegotiating electricity from retail to wholesale rates (a 35% cut in power costs within 30 days) and changing filter-press mesh size to eliminate near-daily equipment failures. Current operating costs are reported below $800 per tonne of concentrate. Production restarted in 2026, reportedly around three months ahead of an original July target, with the company targeting 5,000 tonnes per year of capacity by year-end and cumulative 2026 throughput of roughly 1,847 tonnes.
Two distinct expansion paths are on the table. The first to 10,000 tonnes per year is described as low-capex (under $1 million) and fully financed, since the plant's off-the-shelf equipment already has spare capacity and the only bottleneck is a second filter press. The second, a larger expansion toward 25,000, to potentially 50,000 tonnes per year, is being discussed with the Brazilian Development Bank and the US International Development Finance Corporation, but rests on a 2022-vintage feasibility study that Cunha himself says is no longer reliable, given subsequent changes to the processing flowsheet.
Commercially, South Star reports a flake-to-fines split of roughly 70/30, ahead of original design, with flotation grades of 93-97% Cg and 99.95% Cg purity validated downstream. Sales are spread across multiple US buyers, with additional niche markets - such as agricultural graphite at a substantial premium to commodity pricing - cited as a way to avoid dependence on any single customer. Cunha frames the sector's core risk as Chinese pricing behaviour rather than product-specific competition, noting the absence, so far, of any floor-pricing mechanism for graphite comparable to those emerging in rare earths.
With CEO ownership of roughly 40%, funded through the company's near-collapse, and graphite's growing framing as a supply-chain security issue for Western defence and industrial policy, South Star presents a relatively de-risked near-term production story layered with a larger, currently unquantified expansion option.
View South Stat Battery Metals company profile: https://www.cruxinvestor.com/companies/south-star-battery-metals
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What is Company Interviews?
An insight into junior mining and opportunities to invest.
Company Interviews, a Crux Investor show, exists to cut through the jargon, bias and bluster.
Matthew Gordon, and guest host Merlin Marr-Johnson hone in on the important factors that indicate a company's strong footing for growth and success.