Ms. Ana Cabral reports

SIGMA LITHIUM SELLS 100,000T OF HIGH PURITY LITHIUM FINES; ADVANCES MINING REMOBILIZATION; APPOINTS DISTINGUISHED AGRIBUSINESS LEADER AND FORMER MINISTER AS NEW BOARD MEMBER

Sigma Lithium Corp. has sold 100,000 tonnes of high-purity lithium fines. The company also provides an update of its mining remobilization activities, including the signing of a working capital revolving facility and closing of its first tranche.

Sigma Lithium is honoured to announce the appointment of Katia Abreu, a distinguished agribusiness leader and former Minister of Agriculture, as its new independent board member.

Sale of high-purity lithium fines

The company concluded the first sale of its high-purity lithium fines of 100,000 tonnes, which was stored at the port of Vitoria, at market prices (based on the Shanghai Metals Market (SMM) index). The price was equivalent to an adjusted net final price of $125 (U.S.) per tonne, the SMM price for material within 1.2 per cent to 1.5 per cent of lithium oxide content (currently priced at $150 (U.S.) per tonne to $230 (U.S.) per tonne). This first sale will generate net revenues of approximately $11-million (U.S.).

The company has an additional 850,000 tonnes of high-purity lithium fines available for sale at its plant. This material was produced during 2024 and 2025 by Sigma Lithium's environmental state-of-the-art technology to dry stack wet lithium fines generated by its Greentech industrial plant 1 while reusing 100 per cent of the water consumed by the process.

Mining remobilization

Sigma Lithium is advancing its remobilization plan at its Mine 1, as part of the successful implementation of a complete restructuring of its mining operations in Q4 2025. The company's technical leadership undertook the control and planning of its mining operations while execution continues to be subcontracted. The objective was to increase mining safety and operating efficiency while ensuring operational resiliency and the perpetuity of the company's mining reserves of over 100 million tonnes.

The mine restructuring has been executed in phases, according to plan: leasing large mining equipment while subcontracting mining personnel (drivers and operators) and small-scale mining equipment. The new technical mining leadership of the company is now responsible for directing and controlling blasting and drilling while two leading subcontractors have the role of carrying out execution (operating personnel level).

These steps have been conducted with the financial support of Sigma Lithium's large global clients, which are providing contractual collateral and working capital lines against future production, replacing additional third party capital that could have been required during the mine remobilization.

The purchased large-scale equipment, combined with the subcontracted smaller equipment, is expected to almost triple previous mining and earth-moving capacity. The company's remobilization of mining personnel and smaller equipment continues and is expected to be concluded during January, 2026. The company will provide guidance for 2026 output once production resumption reaches a steady state during the first quarter.

This pivot away from relying entirely on a third party mining contractor (as the case for Sigma Lithium's initial 2022/2023 mine commissioning) also has the target of providing industrial cadence, continuously matching raw material supply to the increased industrial processing capacity of its Greentech industrial plant 1, thus preparing the company for a multipit operation, with increasing mining volumes from its various assets, steadily supplying ore to Greentech plants 2 and 3 while reducing mine costs and further consolidating Sigma Lithium's as one of the lowest-cost producers in the industry. The steady provision of ore also has the objective to derisk cash flow during the planned coming commissioning of Greentech industrial plant 2, which is to double lithium oxide concentrate production capacity.

Working capital agreement

Sigma Lithium signed an agreement with a major client aimed at providing the company with working capital during 2026. The agreement consists of working capital being provided against monthly sales at spot market prices totalling 70,500 tonnes (by the end of 2026). The first tranche of the facility for $5-million (U.S.) has closed.

Appoints new board member

Sigma Lithium is honoured to announce the appointment of Ms. Abreu, a distinguished agribusiness leader and former Minister of Agriculture, as its new independent board member.

The board of directors of Sigma Lithium has unanimously approved the nomination of Ms. Abreu to replace Eugenio de Zagottis, who is stepping down from the board to focus on his other business activities.

Ms. Abreu is one of Brazil's most prominent agribusiness leaders and entrepreneurs. She was president of the Confederation of Agriculture and Livestock of Brazil (CNA) for five years, representing over one million agricultural producers nationwide. She served as senator in the federal congress for multiple terms, winning several landslide elections from 2007 to 2022, representing her home state of Tocantins, one of Brazil's largest agricultural producers.

While in the Senate, Ms. Abreu chaired the foreign relations and defence committee, where she gained significant geopolitical experience. Later, she was a member of the economic affairs committee. Ms. Abreu also served as Brazil's Minister of Agriculture, acquiring significant experience in Brazilian public policies for natural resources.

Currently, Ms. Abreu holds several board and advisory positions for companies listed in the United States and in Canada. She is also a senior board adviser for the Brazilian Mining Institute (IBRAM). One of her board positions includes New York Stock Exchange-listed JBS Inc., one of the world's largest food companies, where she represents BNDESPar, the investment arm of BNDES (the Brazilian National Bank for Economic and Social Development).

"We are very enthusiastic to welcome Katia Abreu as an independent director to our board," said Ana Cabral, chief executive officer and co-chairperson of Sigma Lithium. "She has tremendous experience creating value in the highly regulated natural resources industry in Brazil. Katia has managed to become one of the most admired Brazilian leaders across the political spectrum. She has uniquely followed her successful trajectory as an agribusiness entrepreneur by holding several leadership positions representing the sector, culminating with her service as a senator for 16 years. During her multiple tenures in the Senate, she held chairmanship roles in key committees such as foreign relations, defence and economic affairs.

"As president of the national association and Minister of Agriculture, she contributed to turn agribusiness into one of Brazil's most admired sectors (making agro pop) while creating public policies that further established the sector as one of the economic engines of Brazil while working with her colleagues at the Ministry of the Environment to drive environmental policy and social policies that lifted entire communities. Her experience will be invaluable to Sigma Lithium during another transformational period for the company. During her tenure, we will be advancing with building our second Greentech industrial plant that is expected to double our production capacity. We also will be entering the planning stages for the construction for our third plant in back-to-back sequence."

Ms. Cabral continued: "We would like to profusely thank Eugenio for his intense and dedicated service on the board during this extremely important period in our company's growth trajectory. He was a great mentor and has brought a wealth of invaluable expertise to the Sigma Lithium team, greatly helping the company navigate what has been one of the most challenging periods for our leadership, driven by the external volatile market conditions."

Marcelo Paiva, co-chairman of Sigma Lithium and co-founder of A10 Invest, stated: "On behalf of Sigma Lithium's shareholders, we would like to thank Mr. Zagottis for his significant contribution to the company, where he helped steer our leadership to successfully navigate the severe lithium market downturn that occurred during his tenure as a board member, from July, 2024, to the end of 2025, which also encompassed the intense volatility in 2025 generated by global tariff uncertainty."

Ms. Abreu will be replacing Mr. Zagottis as a member of the audit, finance and risk committee and the people and governance committee. The board will maintain a majority of independent directors and will have female representation of 40 per cent.

About Sigma Lithium Corp.

Sigma Lithium is a leading global lithium producer dedicated to powering the next generation of electric batteries with socially and environmentally sustainable lithium oxide concentrate.

The company operates one of the world's largest lithium production sites -- the fifth-largest industrial mineral complex for lithium oxide concentrate -- at its Grota do Cirilo operation in Brazil. Sigma Lithium is at the forefront of environmental and social sustainability in the electric battery materials supply chain, producing quintuple-zero green lithium: zero coal power, zero tailings dams, zero utilization of potable water, zero use of hazardous chemicals and zero accidents.

Sigma Lithium currently has a nameplate capacity to produce 270,000 tonnes of lithium oxide concentrate on an annualized basis (approximately 38,000 to 40,000 tonnes of lithium carbonate equivalent) at its mine and state-of-the-art Greentech industrial plant. The company is now constructing a second plant to double its production capacity.

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