Sigma Lithium Provides Drilling Program Update Confirming High Grade and Low Impurity Lithium Resource

Results to Date Consistent with Significant Resource Expansion Potential

VANCOUVER, Sept. 13, 2018 - SIGMA Lithium Corporation ("Sigma" or the "Corporation") (TSX-V: SGMA) is pleased to provide updated assay results on the Company’s ~30,000m diamond drilling campaign of lithium deposits at its Grota do Cirilo Property. The project’s existing lithium mineral resources is expected to significantly increase, as previously identified in Sigma’s existing National Instrument 43-101 (“NI 43-101”) independent technical report filed earlier in 2018.

“Our August drilling results confirm the high quality and low impurities of this substantial lithium resource,” said Calvyn Gardner, CEO of Sigma. “Importantly we have received strong indicators from exploration holes in three of our top lithium deposits, which supports our expectation the total resource volume has the potential to be significantly increased. We are preparing to ship samples to potential offtake partners and look forward to providing further updates as we continue to advance the project towards production and validate additional mineral resources.”


Drill Results for August 2018 on Grota do Cirilo Lithium Property

In late May 2018, Sigma commenced a ~30,000m diamond (HQ core) drilling campaign to extend and develop the existing Grota do Cirilo spodumene lithium mineral resource. Once completed, this drilling campaign will be the basis for a revised mineral resource estimate, to be prepared by SGS Canada Geostat (“SGS”), which is expected to be finalized by the end of 2018.


The drilling program is divided into two work streams:

- A 6,000m drilling program for the definitive feasibility study of the Xuxa deposit, Sigma’s foothold mine. The drilling consists of 27 holes focusing on: (i) increasing the size of the mineral resource, (ii) producing metallurgical samples at depth and (ii) conducting geotechnical studies;

- A 25,000m definition drilling campaign for the additional four lithium deposits in the property (Barreiro, Lavra do Meio, Murial and Nezem do Chicao) contemplating drilling 96 holes at Barreiro, 19 at Lavra da Meio, 30 holes at Murial and 4 holes at Nezem do Chicao

The drilling assays received for the month of August 2018 from the definition drilling campaign for three of the lithium deposits (Xuxa, Barreiro and Murial) are described below:


1. Xuxa

- The Xuxa drilling campaign contemplates 27 holes (6186m), all of which all have been completed, with an average depth of 229m. Sigma has received 30% of the assay results to date and the current results indicate the potential to increase the level of confidence of mineral resources between 0m and 200m vertical from the surface.

- All the assays received demonstrate the continuity of the mineralization down to 200m and in some cases even down to 285m. The expansion of the mineralized zone down to 200m at Xuxa will allow us to further upgrade the mineral resource, adding additional volume. The geological 3D model is currently being updated, while the remaining assays are pending.

- Highlights from the Xuxa assays are:

-- 22.5m at 1.86% Li2O from 152.1m to 174.6m interval (drill hole DH-Xuxa - 72)
-- 15.9m at 1.81% Li2O from 162.1m to 178.0m (drill hole DH-Xuxa -74)
-- 12.2m at 1.78% Li2O from 170.2 m to 182.4m (drill hole DH-Xuxa -75)


2. Barreiro

- The Barreiro drilling campaign contemplates 96 holes (16000m), of which 84 holes have been drilled to date, for a total of 12,752m. Average thickness of the deposit is around 35m, the average drill hole depth is around 151m and deepest hole drilled to-date is 369m.

- The deeper holes are the results of the pegmatite being over 140m thick in these areas.

- Sigma has received 50% of the assay results with an average grade of 1.4% Li2O in the pegmatite indicating that Barreiro could potentially become a significant deposit, on a similar scale to the Xuxa deposit.

- Highlights from the Barreiro assays are:
-- 38.0m at 1.79% Li2O from 117.0m to 155.9m (drill hole DH-Bar-40)
-- 31.2m at 1.76% Li2O from 187.9m to 219.1m (drill hole DH -Bar-43)
-- 33.1m at 1.68% Li2O from 46.9m to 80.0m (drill hole DH-Bar-47)
-- 33.9m at 1.78% Li2O from 98.1m to 132.0m (drill hole DH-Bar 42)


3. Murial

- The Murial drilling campaign contemplates 30 holes (4500m), of which 20 holes have been drilled to date, for a total of 3025m. Average thickness of the deposit is around 20m, the average drill hole depth is around 151m and deepest hole drilled to-date is 251m.

-Sigma has received 25% of the assay results to-date.

- Highlights from the Murial assays are:
-- 23.6m at 1.31% Li2O from 64.2m to 87.7m (drill hole DH-Mur-2)
-- 37.6m at 1.2% Li2O from 84.5m to 122.1m (drill hole DH -Mur-5)

The following table sets out the latest assay results received for the month of August 2018:

Pegmatite	DH_ID	From	To	Int1	Geo	Li2O % Average
Barreiro	DH-BAR-40	117.0	155.9	38.8	PG_Li	1.8%
Barreiro	DH-BAR-40	157.6	163.3	5.7	PG_Li	1.0%
Barreiro	DH-BAR-40	167.7	170.3	2.6	PG_Li	0.3%
Barreiro	DH-BAR-41	54.2	84.5	30.4	PG_Li	1.6%
Barreiro	DH-BAR-41	91.5	92.7	1.2	PG_Ab_Q	1.0%
Barreiro	DH-BAR-41	95.7	97.2	1.6	PG_Ab_Q	0.2%
Barreiro	DH-BAR-43	165.1	167.3	2.2	PG_Ab_Q	0.1%
Barreiro	DH-BAR-43	183.0	186.9	3.9	PG_Li	1.6%
Barreiro	DH-BAR-43	187.9	219.1	31.2	PG_Li	1.8%
Barreiro	DH-BAR-47	46.9	80.0	33.1	PG_Li	1.7%
Barreiro	DH-BAR-48	86.1	119.1	33.0	PG_Li	1.6%
Barreiro	DH-BAR-51	20.0	37.5	17.5	PG_Li	1.2%
Barreiro	DH-BAR-42	98.1	132.0	33.9	PG_Li	1.8%
Xuxa	DH-XUX-72	152.1	174.6	22.5	PG_Li	1.9%
Xuxa	DH-XUX-73	86.0	91.9	5.9	PG_Li	1.7%
Xuxa	DH-XUX-73	94.2	104.1	9.8	PG_Li	1.6%
Xuxa	DH-XUX-74	162.1	178.0	15.9	PG_Li	1.8%
Xuxa	DH-XUX-75	170.2	182.4	12.2	PG_Li	1.8%
Xuxa	DH-XUX-75	185.2	186.6	1.3	PG_Li	1.0%
Murial	DH-MURIAL-02	64.2	87.7	23.6	PG_Li	1.3%
Murial	DH-MURIAL-03	154.3	156.3	2.0	PG_Ab_Q	0.0%
Murial	DH-MURIAL-03	165.0	169.9	4.1	PG_Ab_Q	0.0%
Murial	DH-MURIAL-05	153.3	162.8	9.6	PG_Ab_Q	0.4%
Murial	DH-MURIAL-06	84.5	122.1	37.6	PG_Li	1.2%

(1) The intervals reported in this table represent drill intercepts and insufficient data is available at this time to state the true thickness of the mineralized intervals


Quality Control

QA/QC program involving blank samples (4% of the sampling stream), standard samples (4% of the sampling stream) and field duplicates (6% of the sampling stream) has been established during sampling. A further 6% of the mineralized samples will also be sent to the ALS Laboratory in Vancouver, British Columbia for pulp duplicates once the campaign is over. All assays are analyzed at SGS’s Belo Horizonte laboratory using a multi-elements peroxide fusion ICP-AES on half-core 1 kg sample selected by geologist.


ABOUT SIGMA

Sigma Lithium Corporation is developing a world class lithium hard rock deposit with high grade and exceptional mineralogy at its Grota do Cirilo property in Minas Gerais Brazil. Sigma commissioned its Phase I production plant and has commenced the production of battery-grade spodumene concentrate from its high-quality deposits. Sigma’s corporate mission is to execute its strategy while embracing environmental, social, and governance principles. The Corporation is on track to become an ultra-high quality spodumene concentrate supplier to the lithium battery industry worldwide.

Sigma shareholders include some of the largest ESG (environmental, sustainability, governance) focused institutional investors in the world. Sigma plans to commence construction of a commercial-scale lithium concentration plant in 2019, becoming a fully-operational sustainable lithium producer in 2020.

Sigma, through its subsidiaries, has 28 mineral rights in four properties spread over 188 km2 and 18,887 hectares - with over 200 lithium bearing pegmatites and 11 former historical lithium mines. The Grota do Cirilo property, Sigma’s primary focus, includes 10 mining concessions (mining production authorizations).

Sigma has a NI 43-101 technical report on the Grota do Cirilo property prepared by SGS, which includes estimated measured and indicated resources of approximately 12,900,000 tonnes for its main deposit (8,502,000t measured and 4,385,000t indicated), with a high average grade of 1.56% (for approximately 500,000t of LCE). The technical report also includes estimated inferred resources of 608,348t and further notes the potential for significant resource expansion.


Qualified Person

The resources estimates in this news release are included in (and the estimated LCE is derived from the resource estimates included in) the technical report titled “Technical Report Northern and Southern Complexes Project, Araçuai and Itinga, Brazil, Sigma Lithium Resources Inc.” which has an effective date of January 29, 2018 and was prepared by Marc-Antoine Laporte, P.Geo, M.Sc. of SGS. Mr. Laporte is a qualified person as defined by NI 43-101 and is independent of Sigma. The report is available at www.sedar.com. Mr. Laporte has also reviewed and approved the scientific and technical information in this news release.



For additional information please contact:

SIGMA Lithium Resources Corporation
Company Contact:
Ana Cabral, Vice – Chairman, Director of Business Development and Investor Relations
+55 11 2985-0089
ana.cabral@sigmaca.com
www.sigmalithiumresources.com

Investor Relations Contact:
KCSA Strategic Communications
Valter Pinto / Scott Eckstein
(212) 896-1254
Valter@KCSA.com



FORWARD-LOOKING STATEMENTS

This news release contains forward-looking statements relating to the objectives of the Corporation, the potential for increased resources, concentration plant construction, achieving sustainable production and other statements that are not historical facts. Readers are cautioned not to place undue reliance on forward-looking statements, as there can be no assurance that the plans, intentions or expectations upon which they are based will occur. By their nature, forward-looking statements involve numerous assumptions, known and unknown risks and uncertainties, both general and specific, that contribute to the possibility that the predictions, forecasts, projections and other forward-looking statements will not occur, which may cause actual performance and results in future periods to differ materially from any estimates or projections of future performance or results expressed or implied by such forward-looking statements. These assumptions, risks and uncertainties include, among other things: the state of the economy in general and capital markets in particular, and investor interest in the business and future prospects of Sigma.

The forward-looking statements contained in this news release are made as of the date of this news release. Except as required by law, Sigma disclaims any intention and assumes no obligation to update or revise any forward-looking statements, whether as a result of new information, future events or otherwise, except as required by applicable securities law. Additionally, Sigma undertakes no obligation to comment on the expectations of, or statements made, by third parties in respect of the matters discussed above.

The key risks and uncertainties that could cause actual results or the material factors and assumptions applied in preparing forward-looking information to differ materially from predictions, forecasts, projections, expectations or conclusions are discussed in the “Risk Factors” section of Sigma’s Filing Statement dated April 25, 2018. We caution that the foregoing list is not exhaustive of all possible factors.

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.