Nasdaq- and TSX-V-listed Sigma Lithium has updated the Phase 1 feasibility study for its Grota do Cirilo project, in Brazil, increasing the aftertax net present value (NPV) to $1.6-billion.
The study demonstrates that Phase 1 is financially robust, even as a standalone project before factoring in a potential Phase 2 expansion, the company said on Monday.
The updated Phase 1 feasibility study base case can produce 230 000 t/y of 6% battery-grade lithium for eight years. The base case has an aftertax internal rate of return of 424% and a payback period of only four months.
Sigma noted that there was optionality to increase Phase 1 production to 265 000 t/y, which at 5.2% battery-grade lithium would have a NPV of $1.9-billion.
The updated Phase 1 study reflects increased precision of the technical assumptions, resulting from more than 11 months of detailed engineering, bringing the confidence level of the project to FEL3. As a result, the company reported an updated remaining construction capital expenditure (capex) for Phase 1 of $123.1-million, compared with $113.6-million total capex referenced in the 2019 feasibility study.
The Phase 1 all-in sustaining cost (AISC) was updated in the latest study, with average cash costs of $357/t free-on-board production plant and average AISC of $463/t CIF China.