Sigma Lithium shares sink after Brazil regulator orders mine halt
SGML•Sigma Lithium suspended mining and industrial production at its Grota do Cirilo mine after Brazil’s mining regulator ordered a halt, sending its Toronto-listed shares down more than 19%. The company maintained its fiscal 2027 production forecast of 330,000 metric tons of lithium oxide concentrate but postponed its 12-month forecast of 240,000 metric tons by three months.
1. Mine suspension
Sigma Lithium said it suspended mining and industrial production at its Grota do Cirilo operation on Sept. 30 while awaiting a federal appeals court ruling. The suspension followed an order from Brazil’s mining regulator, ANM, citing an unspecified “imminent risk” and requiring corrective work on a ruptured section of the mine’s north pit eastern slope.
2. Production and operations
Sigma said commercial and recycling operations would continue during the suspension, including sales of high-purity lithium fines, which it said would continue generating cash flow. The company maintained its fiscal 2027 forecast of 330,000 metric tons of lithium oxide concentrate but postponed by three months its 12-month production forecast of 240,000 metric tons.
3. Environmental injunction
The federal court review concerns Sigma’s emergency motion challenging a preliminary injunction tied to its environmental licences. The injunction stems from a civil suit by the Federation of Quilombola Communities of Minas Gerais, which argues the project falls within the area of influence of the Bau Quilombola community; Sigma disputes the claim and said it would pursue further appeals if the court rules against it.
