Sigma Lithium Announces Selection of NASDAQ as Its U.S. Market for Its Dual-Listing

Participation at United Nations High Level Dialogue on Energy Transition and Provides Pre-Construction Update Following Release of 2Q21 Results

VANCOUVER, Sept. 02, 2021 - SIGMA Lithium Corp. ("Sigma" or the "Company") ( TSX-V: SGMA ) ( OTC-QB: SGMLF ) is pleased to report that it selected NASDAQ for its dual-listing in the United States and it will join the United Nations High-Level Dialogue on Energy 2021 Transition that will take place in tandem with the General Assembly opening week on September 24 in New York.

The Company is also pleased to announce the significant progress made during the period towards construction of the plant and mine for phase 1 production ("Phase 1 Production") of its Grota do Cirilo's high grade lithium project in Brazil (the "Project").


SELECTION OF NASDAQ FOR DUAL-LISTING

• The Company has selected Nasdaq as its U.S. market for its dual-listing venue, in order to increase access to U.S. capital markets, while adhering to one of the highest levels of global corporate governance, transparency and diversity in the world.
  • The Company is pleased to report that its corporate policies and Board of Directors are fully compliant with required Nasdaq and SEC governance standards, including diversity recommendation of 40% of representatives of women and minorities.

ENVIRONMENTAL, SOCIAL AND GOVERNANCE

• The Company will join the United Nations High-Level Dialogue on Energy 2021 Transition that will take place in tandem with the General Assembly opening week on September 24 in New York.
• The Company has demonstrated its alignment with the Paris Climate Accord and has targeted to reach net zero carbon emissions after its second year of production in 2024.
  • 26 years ahead of U.N targets for Net Zero emissions in 2050 and six years ahead of U.N Decade of Action targets outlined at 2030 Agenda for Sustainable Development and the Paris Agreement on climate change.
  • Brazil is one of the 10 Global Champions on Energy Transition for the UN High-Level Dialogue on Energy 2021 together with Denmark, Germany, United Kingdom, amongst others.

• The Company's humanitarian relief initiative for the population living in extreme vulnerability at the Vale do Jequitinhonha (including distributing medical facilities supplies and meals) has been replicated by the local business community, in a pioneering demonstration of social entrepreneurship by the Rotary Club of Ara?uai.
  

PHASE 1 PRE-CONSTRUCTION

The Company has reported unaudited financial and operating results for the second quarter ended June 30, 2021 ("2Q21") including a comprehensive technical, operational and corporate update to August 30, 2021, detailing the significant progress made during the period towards Phase 1 Production of its Project.

Both the financial statements and an MD&A are available on SEDAR (www.sedar.com) and on the Company's corporate website at the following links: https://www.sigmalithiumresources.com/wp-content/uploads/2021/09/Sigma-FS-Q2-2021-Final.pdf and https://www.sigmalithiumresources.com/wp-content/uploads/2021/09/Sigma-MDA-Q2-2021-final.pdf.

Highlights include:

PLANT PRE-CONSTRUCTION

• All detailed engineering and preparation for civil construction workstreams continued to advance on schedule and on budget.
• First milestones of construction were achieved.
  • Completed clearing, grubbing and topsoil removal for the plant.
  • Completed the final geotechnical model on the plant site, concluding design and calculations of the civil foundations and total volumes for the bulk earth moving (cut and infill).
    • Contracts for bulk earthworks are in the bidding phase and are to be awarded by the third quarter of 2021.
  • Completed detailed topographic survey for both plant and non-plant area to optimize layout design, minimizing excavation.
    • Building a detour road around the construction site for public vehicles.
  • Completed both the final geotechnical and hydrogeological models as well as the analysis for the two pits of the Project's first mine (the "First Mine").
• Appointed Promon Engenharia, a Brazilian engineering and construction company, to join Australian Primero Engineering to complete detailed engineering and manage civil construction.
• All design-related activities of the production plant for the First Mine (the "Production Plant") were completed to include consideration for a future parallel production plant for the Second Mine.
  • Key items completed: process plant preliminary design, layout and 3D modeling, standard drawings and packages and associated workstreams relating to mechanical, piping, concrete & structural, electrical, instrumentation and controls.
• The Company is finalizing an updated project execution plan to augment construction readiness.

ESG-CENTRIC DEVELOPMENT AND OPERATIONS OF FIRST MINE

• The Company has also completed the final optimized design of the two pits and waste piles of the First Mine (with final operating parameters: berm, ramp, ultimate wall slope angles). Designed the ROM pad for Production Plant together with Promon.
  • A key element of the environmental strategy for Production Phase 1 was the decision to open the First Mine as two separate pits to preserve the Piauí River's seasonal "stream" and its surrounding ecosystems.
  • Optimized pits for the First Mine have the benefit of additionally enhancing the life cycle analysis of the Project by substantially decreasing its carbon footprint by:
    • Decreasing the vegetation suppression of trees in the construction of the pit.
    • Segregating the piles of mined waste and processed tailings with the goal of potentially recycling the tailings into ancillary industries, promoting a circular economy.
• Developed a comprehensive grade control program utilizing geostatistical methods to ensure feed grades are maintained within the expected range. The proposed grade control system will be designed to minimize schist waste rock dilution with the pegmatite ore recovery at the pit.

CAPEX & BUDGET

• An updated capital expenditure ("Capex") budget with increased accuracy is in progress, with "firm quotes" for ~70% of construction items.
  • The Company intends to start placing orders for long-lead items during the third quarter of 2021, reserving manufacturing slots with vendors whose equipment is on a critical path for construction.
  • The contracts for earth moving and civil construction and the orders for long lead equipment items will be funded with existing cash earmarked for construction.
  • The Company has also formulated a procurement strategy to derive maximum Capex effectiveness. Appointed TSX Advisors Ltda., specializing in domestic and global procurement, including equipment and import logistics to Brazil.

PHASE 2 FEASIBILITY STUDY UPDATE

• The Company has significantly advanced its feasibility study for the Phase 2 Production ("Phase 2 Production"), contemplating potentially doubling the Project's total capacity to 440,000 tons per year.
• The Company and Primero completed all the metallurgical and variability pre-feasibility test work at SGS Lakesfield in Canada with the aim of customizing a flowsheet to process the spodumene from the Project's second mine ("Second Mine").
  • The DMS metallurgical testing (pilot plant scale) achieved remarkable 60.7% Li2O recoveries, producing a battery grade concentrate of 6.11% Li₂O.
  • High recoveries are a result of the Second Mine having exceptional mineralization, similar to the First Mine, with large crystals of coarse spodumene.
  • The results demonstrate that the spodumene from the Second Mine can be successfully processed in an environmentally friendly DMS plant, with similar flowsheet to the Production Plant for the First Mine (without requiring a significantly more capital-intensive and less environmentally friendly flotation process).
• The Company completed all field work for the preparation of Phase 2 Production pre-feasibility study, including geotechnical drilling and hydrogeological analysis.
• Additional drilling continues on the Second Mine seeking to both increase the mineral resource and to strengthen the geological data for the reserve block model (mining plan design).
  • The Company is currently working on the mining plan and final geotechnical modelling of the Second Mine.
• The Company completed a preliminary economic assessment for Phase 2 Production, projecting mining an average of 1.68Mt per year during approximately 12.7 years of projected mine life, which was included in an updated feasibility study report filed on SEDAR on July 15, 2021.
  • Projects significant economies of scale for Phase 2 Production, expected to result from the low Capex of adding a second environmentally-friendly processing line and vertically integrating it to the Second Mine and to the Production Plant.

PHASE 3 EXPLORATION & DEVELOPMENT OF OTHER DEPOSITS WITHIN THE PROJECT AREA

• The Company is accelerating its exploration activities in the areas covered by its portfolio of mineral rights to rapidly increase the scale of the Project's estimated mineral resources by the first quarter of 2022 with the goal to further:
  • Increase the Projected mine life at the expanded production levels of 440,000 tons per year during Phase 1 and 2 productions.
  • Increase production output after 2024 in a third production phase should EV penetration growth continue to accelerate, and lithium demand forecasts continue to demonstrate strength.
  • Determine the ultimate potential of the Project's mineralization while demonstrating its uniqueness and high quality.

CORPORATE SUMMARY UPDATE

• The Company maintains adequate liquidity and rigorous financial discipline. As of August 30, 2021, the Company has $37.6 million (US$29.7 million) in cash and cash equivalents, out of which approximately $34.4 million (US$28 million) is held in a construction-segregated savings account (not subject to any restrictions and readily available for disbursement).
  • The Company expects to have sufficient liquidity to conduct pre-construction activities as well as finance all of the ongoing workstreams contemplated by the Company's strategy to accelerate the development of Phase 2 Production.
• In August 2021, the Company was selected to represent Brazil as a delegate at the global meetings of the International Organization for Standardization (ISO), in the technical committee for lithium (TC 333) to promote the standardization in the field of lithium mining, concentration, extraction, separation and conversion.
• Consistent with its retention policies to manage human capital as well as with its ethos of aligning incentives amongst all stakeholders and shareholders, most of the compensation of the Company's Board of Directors is equity-based.
  • The Company granted an aggregate of 739,000 Restricted Share Units to Directors. Ana Cabral-Gardner and Calvyn Gardner were not awarded equity compensation.
    

COVID-19

• The Company continues to conduct all activities with strict COVID-19 protocols in place for access to the construction site in light of the "Delta Variant".
  • The Company is pleased to report that its personnel on site did not suffer any infections during 2Q21 to date.
  • The town of Itinga, where Sigma is headquartered, kindly extended its vaccination program to Sigma employees, demonstrating the strength of the host community's support to the Company.

INVESTOR VIDEO CONFERENCE CALL September 8, 2021 at 11:00 AM (EST) Zoom video call registration link: https://us06web.zoom.us/webinar/register/WN_b6lO9Yo3TjOlQT9XtJRx1g Zoom ID: 865 1276 0999 Join by phone using the following dial in: North America: +1 646 558 8656, UK: +44 203 481 5237, Brazil: +55 11 4680 6788

SUMMARY Sigma Lithium to join NASDAQ Company to present at United Nations High-Level Dialogue for Energy 2021 Transition Conference on Sept. 24 in New York Company on target to begin production in 2022 and achieve net zero carbon emissions ahead of the targets announced by the United Nations for the Decade of Action Against Climate Change Investor call set for Sept. 8 at 11 a.m. EST

ABOUT SIGMA LITHIUM

Sigma is a Canadian company developing, with an environmental sustainably ESG focused strategy, the largest hard rock lithium deposits in the Americas, located in its wholly owned Grota do Cirilo Project in Brazil. The Company has been producing low carbon high purity lithium concentrate at an on-site demonstration pilot plant since 2018. This pilot production has been an important part of the successful commercial strategy of the Company, shipping samples of its low carbon "green & sustainable" high purity lithium to leading global potential customers, for product certification and testing, with the goal of participating in the rapidly expanding electric vehicle ("EV") supply chain.

The Company is in pre-construction and detailed engineering of an environmentally friendly, fully automated, dense media separator ("DMS") production plant, that will apply proprietary algorithms to digitally control the dense media. The production plant will be vertically integrated into the Company's mining operations, exclusively utilizing as feedstock the high purity spodumene ore with exceptional mineralogy from the Project. The production plant will process the spodumene ore into a high purity 6% battery-grade lithium concentrate engineered to the specifications of its customers in the lithium-ion battery supply chain for EVs.

The Company continues to demonstrate its commercial and market relevance by significantly advancing its strategic goals on three fronts: near-term production scheduled for 2022, completing the studies for the viability of production expansion contemplated for 2023, and the determination of the ultimate extent and unique high-purity quality of mineral resources at the Company's wholly-owned Grota do Cirilo Project, all while maintaining its strategic leadership in ESG in the lithium supply chain.

In order to secure a leading position supplying the clean mobility and green energy storage value chains, the Company has adhered consistently to the highest standards of ESG practices, which were established as part of its core purpose at inception in 2012. The production process will be powered by clean energy and the Company will use state-of-the art water recirculation circuits in its processing combined with dry stacking tailings management. The DMS process of the production plant does not utilize hazardous chemicals, as a result its tailings are 100% recyclable into ancillary industries, such as ceramics.

FOR ADDITIONAL INFORMATION PLEASE CONTACT

Daniel Abdo
(Sao Paulo) +55 11 2985-0089
daniel.abdo@sigmaca.com
ir@sigmaca.com

Vitor Ornelas
(Sao Paulo) +55 11 2985-0089
vitor.ornelas@sigmaca.com

LinkedIn	Sigma Lithium
Instagram	@sigmalithium
Twitter	@SigmaLithium

FORWARD-LOOKING STATEMENTS

This news release includes certain "forward-looking statements" under applicable Canadian securities legislation including statements relating to the ultimate duration, impact and severity of the COVID-19 pandemic (including its impact on financial markets and national and multinational economies generally, and its impact on the growth of the electric vehicle market and other impacts on the demand for lithium products) and other forward-looking statements. Forward-looking statements are necessarily based upon a number of estimates and assumptions that, while considered reasonable, are subject to known and unknown risks, uncertainties, and other factors which may cause the actual results and future events to differ materially from those expressed or implied by such forward-looking statements. All statements that address future plans, activities, events, or developments that the Company believes, expects or anticipates will or may occur are forward-looking information, including statements regarding the potential development of resources and drilling plans which may or may not occur. Forward-looking statements and information contained herein are based on certain factors and assumptions regarding, among other things, the ability to complete the Annual Filings and Interim Filings; the market price of the Company's securities, metal prices, exchange rates, taxation, the estimation, timing and amount of future exploration and development, capital and operating costs, the availability of financing, the receipt of regulatory approvals, environmental risks, title disputes, litigation risks, failure of plant, equipment or processes to operate as anticipated, accidents, labour disputes, claims and limitations on insurance coverage and other risks of the mining industry, changes in national and local government regulation of mining operations, and regulations and other matters including the COVID-19 pandemic. There can be no assurance that such statements will prove to be accurate, as actual results and future events could differ materially from those anticipated in such statements. Accordingly, readers should not place undue reliance on forward-looking statements. The Company disclaims any intention or obligation to update or revise any forward-looking statements, whether as a result of new information, future events or otherwise, except as required by law. For more information on the risks, uncertainties and assumptions that could cause our actual results to differ from current expectations, please refer to our public filings available at www.sedar.com.

Neither the TSX Venture Exchange nor its Regulation Services Provider (as that term is defined in the policies of the TSX Venture Exchange) accepts responsibility for the adequacy or accuracy of this news release.