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Sigma Lithium Significantly Increased Audited Mineral Resource BY 27% to 109Mt: Grota Do Cirilo IN Brazil Becomes World’S 4th Largest Operating Industrial Pre-Chemical Lithium Beneficiation & Mining Complex; Grota Do Cirilo Expected to

Resource Estimates Metallurgy & Processing

SIGMA LITHIUM SIGNIFICANTLY INCREASED AUDITED

MINERAL RESOURCE BY 27% TO 109Mt: GROTA DO CIRILO

IN BRAZIL BECOMES WORLD’S 4th LARGEST OPERATING

INDUSTRIAL PRE-CHEMICAL LITHIUM BENEFICIATION &

MINING COMPLEX; GROTA DO CIRILO EXPECTED TO

FURTHER INCREASE TO 150Mt

INVESTOR VIDEO CONFERENCE CALL

February 1, 2023, at 1:00 PM (EST)

Registration Link for Zoom video call below:

https://us06web.zoom.us/j/88211037256

Zoom Meeting ID: 882 1103 7256

AUDITED NI 43-101 MINERAL RESOURCE UPDATE VALIDATES SIGNIFICANT SCALE

• Sigma Lithium announces a significant increase in its Audited NI 43 -101 Mineral Resource to

109 million tonnes of measured, indicated and inferred mineral resource at its Sigma Brazil,

100% owned Grota do Cirilo operation at Vale do Jequitinhonha : composed of 94.3Mt of

measured & indicated (“M&I") resource at an average grade of 1.40% Li 2O, together with

additional 14.6Mt of inferred resource at 1.37% Li2O.

o Newly revised NI 43-101 Mineral Resource estimate represents an increase of 27% from the

previous technical report dated January 2023.

o Contained lithium carbonate equivalent tonnage also increase d by 27% as Sigma Lithium

maintained the high quality of its mineral resource while substantially increasing its scale.

• Grota do Cirilo now becomes world’s 4 th largest operating industrial pre -chemical lithium

beneficiation complex, fully integrated with 100% wholly-owned spodumene mining

operations.

o Larger mineral resource demonstrates that Brazil can be an anchor supplier of significant

scale of industrialized lithium materials for the global electric vehicle industry.

• Main objective of 2023 drill campaign fully achieved: results validate the “J-shaped” corridor of

interrelated deposits extending from Barreiro (Phase 2) through NDC-Murial (Phase 3/4).

o Geological model supports a continuous principal pegmatite at NDC-Murial and potential

for a combined NDC-Murial open pit, representing approximately 60Mt of aggregate

measured, indicated and inferred mineral resource, extending over a strike length of 3.2km,

anchored by these two large spodumene pegmatites flanked by subordinated lenses.

• Expanded mineral resource expected to add tangible value for stakeholders, shareholders and

potential strategic parties alike, supporting the integrated production growth of industrialized

and beneficiated pre -chemical lithium in Brazil , as Sigma Lithium aims to triple production

capacity of its “Quintuple Zero Green Lithium”.

UPGRADE OF MINERAL RESOURCES TO RESERVES

• Sigma Lithium believes the increased mineral resources can be seamlessly incorporated into

its current open pit mineral reserves, validated by the Pre-Feasibility Study : A s ignificant

portion of the incremental resource is located within the vicinity of existing mining pits.

o The Company is c urrently preparing a revised Pre-Feasibility Study with new NDC-Murial

strike mining shells and sequencing.

o Sigma Lithium plans to develop the NDC-Murial strike with the benefit from shared mine

infrastructure.

GROTA DO CIRILO MINERAL RESOURCE EXPECTED TO FURTHER INCREASE TO 150Mt

• The Company is focusing its 2024 drill campaign to build on the “J-shaped” lithium corridor

connecting the existing resources of Grota do Cirilo, as follows:

o Drilling at the newly discovered Barreiro Extension pegmatite is expected to extend the

Barreiro pit westward (Figures 5/6), potentially adding 20Mt of mineral resource estimates.

▪ Drilled neighboring pegmatite outcrops support resource connectivity.

o Significant resource growth potential re mains along the NDC-Murial strike (Figure 3) as

mapping of pegmatites remain open at depth, to the west, and to the east.

o Phase 5 drilling in the southern extent of the lithium corridor has identified a new pegmatite

discovery expected to support another 20Mt of potential mineral resources.

DRILLING OF ADDITIONAL 57 TARGETS LOCATED ON SIGMA MINING CONCESSIONS

o Company plans to drill additional 57 spodumene pegmatite targets within mining rights

outside of core Grota do Cirilo, some of which were former artisanal spodumene mines.

SAO PAULO, BRAZIL – (January 31, 202 4) – Sigma Lithium Corporation (“Sigma Lithium ” or the

“Company”) (NASDAQ: SGML, BVMF: S2GM34, TSXV: SGML) , a leading global lithium producer

dedicated to powering the next generation of electric vehicles with carbon neutral, responsibly sourced

lithium materials, is pleased to announce a significant increase of its mineral resource estimate to 109

million tonnes at its Sigma Brazil, 100% owned Grota do Cirilo operation at Vale do Jequitinhonha:

composed of 94.3Mt of measured & indicated (“M&I") mineral resource at an average grade of 1.40%

Li2O, together with additional 14.6Mt of inferred mineral resource at 1.37% Li2O.

AUDITED NI 43-101 MINERAL RESOURCE UPDATE VALIDATES SIGNIFICANT SCALE

The revised audited mineral resource estimate represents a 27% increase when compared to the last

technical report, dated January 2023. The new estimate maintains the high average lithium oxide grade

of the Company’s measured and indicated mineral resources at 1.40% Li2O, above global peer average

as per Figure 1.

Figure 1: Grota do Cirilo is the world’s 4th largest lithium industrial beneficiation & mining complex

currently in operation

Ana Cabral-Gardner, Co-Chairperson and CEO commented: “We are delighted to announce that Grota

do Cirilo became the world’s 4th largest operating industrial pre-chemical lithium beneficiation complex

by mineral resource scale, transforming Sigma Lithium in to one of the largest operating integrated

producers in the global lithium industry. None of this would be possible without the relentless dedication

of our multi-disciplinary team over the years to firmly place Brazil as a sustainability leader in the global

lithium supply chain . Sigma Lithium is the only remaining fully integrated producer of significant scale

wholly owned by financial sponsors, which represents tangible synergistic value for our potential

strategic partners. Over the course of the last year, we managed to fully integrate and operate a state of

the art Greentech lithium industrial beneficiation plant with our Grota do Cirilo mining operation while

validating a sizable 109Mt of mineral resources. Our competitive advantage is now well established, as

we have been delivering the most sustainable lithium concentrate in the world, the “Quintuple Zero Green

Lithium”, while maintain ing low production costs . Together, this supports resilience in our business

model, especially at the current point in the lithium cycle.”

She added, “The sheer scale of the mineral resource revisions increases Sigma’s strategic flexibility to

consider a fourth Greentech industrial pre -chemical beneficiation line, while also contemplating

additional industrial integration further downstream into the production of low-cost lithium sulphate

chemicals. The potential expansion of our current operations will benefit from significant economies of

scale, including existing infrastructure and cost sharing, as compared to our initial phase 1 development

at Grota do Cirilo. All together, the conclusion of this year-long drill campaign represents tangible value

creation for Brazil, for our communities at Vale do Jequitinhonha and our global shareholders.”

Iran Zan, MAIG, co -Head of Geology and co -General Manager, stated: “Once again , our team of

veteran Sigma geoscientists delivered to stakeholders. We believe we have proved our long-held belief

in the existence of a sizable lithium corridor at the Sigma mineral concessions. In a little over seven years,

Grota do Cirilo went from drill core samples to one of the largest lithium mineral resources in the world,

with some of the highest grades and a growth potential to 150Mt. This is thanks to the relentless work

of our outstanding geology, mineralogists, and geoscientists teams. With t oday’s Mineral Resource

update, we are just beginning to demonstrate the sizeable potential of our lithium corridor, and will be

targeting some of the 57 high priority (of 200 mapped) pegmatites in the 2024 campaign.”

Dyonne Hage, co-Head of Geology commented: “We demonstrated the interconnectivity of Grota do

Cirilo’s “J-shaped” strike anchored by the 3 large ore bodies at Barreiro and NDC -Murial. As drilling

advances, we look forward to delivering on our exploration target of reaching 150Mt in Grota do Cirilo by

extending Barreiro westwards and developing Phase 5 .” He added, “We are also very optimistic about

the NDC-Murial strike, which remains open to the east and is accessible through open pit mining. The

deposits show consistent grades and coarse spodumene crystal quality throughout intercepts.”

Figure 2: Sigma Lithium mineral concessions and the Grota do Cirilo “J-shaped” lithium corridor.

The results of the 2023 drill campaign helped prove the interconnectivity of the Phase 3 and 4 NDC-

Murial mineral resources and its subordinated mineralized pegmatites, which had been only partially

delineated in previous drilling campaigns (mainly focused on the anchor ore body of NDC).

In the 2023 campaign, the Company intercepted additional spodumene bearing pegmatite zones at NDC,

including a new deposit of substantial width and lithium oxide grading. Neighboring subordinated

resources have also grown in scale, such that Sigma Lithium is changing its mine plan as the optimized

structure for Phase 3 will now encompass these neighboring pegmatites through a singular open pit. As

a result, the Company believes the increased mineral resources can be seamlessly incorporated into its

mineral reserves by extending the current NDC mining open pit shell, validated by the current Pre-

Feasibility Study.

UPGRADE OF MINERAL RESOURCES TO RESERVES.

This “New NDC” pit contains a total of approximately 40Mt of mineral resource, comprised of 37.8Mt of

M&I resource at 1.42% Li2O and an additional 2.3Mt Inferred at 1.26%. Given geological consistencies

and proximity of the resources, a singular pit is the most efficient design. Additionally, this plan is

expected to save on stripping costs and enable the NDC pit to access the new pegmatite mineralization

while sharing mining infrastructure.

The 2023 drill campaign also increased the scale of the Murial deposit, which sits just 330 meters north

of the newly enlarged NDC resource. The Murial deposit is increasing in size to approximately 16Mt,

comprised of 13.5Mt of estimated M&I resource at 1.25% Li2O with an additional 2.6Mt inferred at 1.29%.

Confidence in the additional scale of Murial, as well as the location of the pegmatite and proximity to

NDC, validates the following geological elements:

(i) Presence of a structural, “J-shaped” lithium corridor that runs through Grota do Cirilo.

(ii) NDC and Murial are likely one continuous principal pegmatite.

Figure 3: Optimized open pit structures for NDC - Murial

Figure 4: The NDC-Murial strike extends 3.2 kilometer North-South.

Drilling confirms that the Murial pegmatite (as well as the new NDC) remain open at depth, to the west

and to the east, leaving room for resource expansion over time. The Company’s 2024 drill campaign will

include step-out drilling to help prove a link between NDC and Murial and build resource density along

the 3.2km NDC-Murial strike.

Figure 5: Density of executed drilling at NDC - Murial, demonstrating potential interconnectivity of

3.2 km strike and flanking pegmatites.

]

BARREIRO EXTENSION TARGET ZONE IS A CONTINUATION OF THE “J-SHAPED” LITHIUM

CORRIDOR

The Company is also focusing the current 2024 drill campaign on demonstrating that the Barreiro mine

extends westwards (“Barreiro Extension”), in a continuation of the existing “J-shaped” lithium corridor.

Additional neighboring outcrops and the ongoing drilling west of Barreiro support potential connectivity

between the Extension outcrop and Barreiro, akin to NDC-Murial. The Company estimates these

Barreiro Extension initiatives may have up to 20Mt of potential additional resource.

Figure 6: Barreiro Extension initiatives extend the “J-Shaped” Grota do Cirilo lithium corridor

further west

Figure 7: Barreiro Extension discovery runs parallel to Barreiro, extending the Phase 2 Mine

Westwards

The Barreiro Extension site is located just west of Barreiro (Phase 2) and represents a continuation of

the spodumene mineralization corridor that moves up through Murial. Two additional spodumene

outcrops discovered between Barreiro and its Extension inform geology of a target area for further

exploration drilling. Prior drilling intercepts from Barreiro also support the thesis of possible connectivity

of these resources. Barreiro Extension results to date include the following drilling intercepts:

DH – PRO – 01 – 1.70% Li2O over 15.70m, including 1.66% Li2O over 14.53m

DH - PRO – 02 – 1.49% Li2O over 14.84m, including 1.86% Li2O over 10.93

SIGMA’S ESTIMATED MINERAL RESOURCE MAINTAIN HIGH GRADE, EVEN AS CUTOFF GRADE

INCREASES

The sensitivity analysis for Sigma Lithium's cumulative Grota do Cirilo resource estimate is presented

below. At a 0% cutoff grade, the cumulative resource totals 110mn tonnes at 1.386% Li2O. Alternatively,

at a high cutoff grade of 1% the cumulative resource totals 92mn tonnes at 1.511%, a reduction of only

16% to total resource over the cutoff window. The exercise displays the consistent, high quality, nature

of the Company's pegmatite resources, and compares favorably to current resource estimates of many

peers.

Figure 8: Sensitivity Analysis of Sigma’s estimated mineral resource potential increase at various

Lithium Cut Off Grades.

1.25%

1.35%

1.45%

1.55%

1.65%

1.75%

80

85

90

95

100

105

110

115

0.0% 0.1% 0.2% 0.3% 0.4% 0.5% 0.6% 0.7% 0.8% 0.9% 1.0%

Lithium Oxide Grading

Resource tonnage (million mt)

Cutoff Grade

Tonnage Lithium Grading

DETAILS ON THE INTERRELATED NDC-MURIAL PEGMATITES (PHASE 3 AND PHASE 4)

Sigma Lithium's Phase 3 and 4 pegmatite strike runs parallel to the mine validated at Phase 2 (Barreiro)

and are in close proximity to each other.

The 2023 drill campaign was completed as part of a strategy to initially increase the scale of NDC, and

demonstrate connectivity to certain other ancillary pegmatites (Maxixe, Tamboril and LDM). The

Company believes it has validated the potential connectivity of NDC and said Phase 4 pegmatites given

intersecting high quality spodumene crystals and persistent spodumene-rich zones. The new Phase 3

and 4 strike extends 3.2 km along a north -south path (Figure 3) from the bottom of the NDC deposit

through Murial. Drilling confirms that the deposits remain open to the west and east.

As prior stated, the campaign has also identified a new pegmatite running underneath the existing

mapped NDC deposit. These discoveries support the Company’s belief that the newly published

resource estimate is likely to increase with additional drilling.

Below are some of the recent drill results at NDC, with “new pegmatite discovery” denoting the new

pegmatite structure below NDC:

DH - NDC - 126 - 1.48% Li2O over 67.33m, including 1.57% Li2O over 63.09m

DH - NDC - 127 - 1.16% Li2O over 15.15 m, including 1.89% Li2O over 7.21m

DH - NDC - 127 - 1.47% Li2O over 50.06 m, including 1.55% Li2O over 47.54m - New pegmatite discovery

DH – NDC - 129 - 1.15% Li2O over 21.20 m, including 1.54% Li2O over 14.46m - New pegmatite discovery

Figure 9: New enlarged Phase 3 NDC optimized pit shell (L) and resource block model (R)

The newly optimized Phase 3 strategy would leave the Murial deposit (330 meters north of the enlarged

Phase 3), to be mined through its own pit. At 16.1Mt of total estimated mineral resource at 1.26% Li2O,

and opportunities to expand this number over time, Murial can support this individual pit strategy. In its

current form, the Murial resource extends 1,160m long by 830m wide, has a true mineralized width

ranging from 5 to 50m and an average depth of 275m. This is the first update to the resource estimate

for Murial since the January 2019 maiden report. The prior mineral resource estimate was 5.6Mt at 1.14%

Li2O M&I with an additional 0.7Mt Inferred. Highlights from the 2023 Murial drill campaign include:

DH - MUR - 126 - 1.19% Li2O over 76.41m

DH - MUR - 034 - 1.47% Li2O over 42.469

DH - MUR - 021 - 1.39% Li2O over 35.12m

DH - MUR - 112 - 1.62% Li20 over 33.88m

DH - MUR - 027 - 1.78% Li2O over 26.09m

DH - MUR - 031 - 1.57% Li2O over 28.75m

Figure 10: Standalone Murial optimized pit shell (L) and resource block model (R)

GROTA DO CIRILO MINERAL RESOURCE EXPECTED TO FURTHER INCREASE TO 150Mt

The Company is currently operating a total of 8 core diamond drills in its leaseholds. Exploration

initiatives will continue into 2024 with drill work targeting additional structures between NDC and Murial

as well as resource expansion across the Barreiro Extension pegmatite as top priorities.

The 2024 drill campaign will commit resources to establish a link between Murial and NDC. The

geological modeling and density of known pegmatites supports a structural trend and potentially

continuous principal pegmatite body, consolidating NDC and Murial. As is, the current NDC-Murial strike

contains nearly 60Mt of resource, ranging in true thickness from ~ 5m to upwards of ~50m, extending

over a length of 3.2km and a width of 1.3km. Improving the resource density along this corridor allows

for fewer, larger, pits, enabling joint infrastructure development akin to leading spodumene projects

globally.

NEWLY CONFIRMED PHASE 5 INFERRED RESOURCE WITH POTENTIAL UP TO 20MT

Finally, the updated technical report also confirms the presence of a Phase 5 resource located within

Grota do Cirilo, with a maiden Inferred estimate of 2.1Mt at an average grading of 1.16% Li2O. The geology

team has conducted infield drilling of this deposit and has mapped neighboring pegmatites, with

exploration to date supporting an estimated resource potential of approximately 20Mt.

As the Company reported on November 1, 2023, further updates of this mineral resource shall continue

as drilling evolves over time. The new Phase 5 discovery is a high value prospect for the Company.

Significant results to date include the following highlight drilling intercepts:

DH - ELV - 08 - 0.98% Li2O over 68.06m, including 1.81% Li2O over 20.46m

DH - ELV - 11 - 1.08% Li2O over 28.46m, including 1.49% Li2O over 15.25m

DH - ELV - 03 - 1.29% Li2O over 22.29m, including 1.42% Li2O over 20.03m

DH - ELV - 05 - 1.24% Li2O over 17.82m, including 1.37% Li2O over 15.86m

DH - ELV - 07 - 0.77% Li2O over 22.2m, including 1.54% Li2O over 7.54m

DH - ELV - 12 - 0.72% Li2O over 14.54m, including 1.52% Li2O over 4.38m

DH - ELV - 04 - 0.79% Li2O over 13.08m, including 1.47% Li2O over 5.85

Figure 11: Phase 5 early block model with resource extension opportunities