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Sigma Reports Exceptional Metallurgical Test Results for Barreiro Deposit Supporting Proposed Phase 2 Production Expansion to 440,000tpy 6% Battery Grade Lithium Concentrate

Drill Results Metallurgy & Processing

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Sigma Reports Exceptional Metallurgical Test Results for Barreiro

Deposit Supporting Proposed Phase 2 Production Expansion to

440,000tpy 6% Battery Grade Lithium Concentrate

 Excellent lithium recoveries of 70% and 66% achieved in HLS gravity separation tests for coarse ore

particles of sizes 6.3mm and 10mm, respectively

 Results support adding a second low-capex DMS production line of 220,000tpy to double planned

capacity without the operational complexity and higher capex of a flotation plant, thus allowing Sigma

to continue to process its lithium ore in a “green” environmentally friendly and sustainable manner

 Indicate Barreiro deposit potential to produce a high-quality 6% lithium concentrate: with high-purity

(very low alkalines and iron) and with coarse particles (large crystals)

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VANCOUVER, British Columbia, January 26, 2021 - SIGMA Lithium Resources Corporation (“ Sigma” or the

“Company”) (TSX-V: SGMA) (OTC- QB: SGMLF) is pleased to announce exceptional results of metallurgical

tests (“Met Tests”) performed to evaluate, among other paramete rs, the recovery of lithium from the Barreiro

deposit proposed to be developed in Phase 2 of the Company’s Grota do Cirilo Project (the “Project”). The Met

Tests included a heavy liquid separation (“ HLS”) test to evaluate the extent to which a gravity-based separation

process, or dense media separation (“DMS”), could successfully recover the lithium from the spodumene ore.

HLS test work done on ore sizes of 6.3mm and 10mm achieved excellent lithium recoveries of 70.2 % and 66.1%,

respectively, producing a 6% Li2O battery-grade sp odumene concentrate within the highest levels of

specifications demanded by the chemical lithium market without the use of flotation or hazardous chemical

reagents, such as sulphuric acid, in the concentration process. This is consistent with Sigma’s intention to continue

to process its lithium ore in a “green” environmentally-friendly and sustainable manner.

The Met Tests results will be used to support the study currently underway to update the technical report titled

“Grota do Cirilo Lithium Project, Araçuaí and Itinga Regions, Minas Gerais, Brazil, National Instrument 43-101

Technical Report on Feasibility Study Final Report”, dated October 18, 2019 (the “ Feasibility Study Report”).

As detailed in its news release of December 7, 2020, the Company commissioned SGS Canada Inc. to update the

Feasibility Study Report to include the mining and processing of ore from the Barreiro deposit with the objective

of doubling the Company’s planned production capacity of high-purity “green & sustainable” 6% Li2O battery-

grade spodumene concentrate to 440,000tpy in Phase 2 of the Project. The Company is in pre-construction phase

(including the EPC and “contract-readiness” of core cons truction suppliers) of its larger-scale lithium

concentration commercial production plant (the “Production Plant”).

The key conclusions of the Met Tests for the update of the Feasibility Study Report are as follows:

 The results indicate that the ore from the Barreiro (Phase 2) deposit can be processed in combination

with ore from the Xuxa (Phase 1) deposit in the same Production Plant, as designed in the Feasibility

Study Report, without requiring major flowsheet modi fications, and thus with low additional capex

needs

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 The results provide validation of the potential for gai ns of scale at the Production Plant resulting from

its doubling of capacity by adding a second DMS production line to process the ore from the Barreiro

deposit

 The results support the potential for substantial economies of scale for the Project as a whole resulting

from the addition of production from the Barreiro deposit

Calvyn Gardner, Chief Executive Officer and Co-Chairman of Sigma’s Board of Directors said: “The doubling

of planned capacity with low additional capex indicated by the Met Tests has the potential to significantly

transform Sigma, enhancing its economies of scale. We are very pleased to have successfully concluded this

crucial step with SGS Canada Inc., as part of the workstreams involved in updating the Feasibility Study Report

with the Barreiro (Phase 2) deposit, which would be full y integrated into the production complex for the Xuxa

(Phase 1) deposit, currently in pre-construction. The Feasibility Study Report has 20.5 million tonnes of measured

and indicated mineral resources (10.3MT measured and 10.2MT indicated) in the Barreiro deposit from which to

support an estimation of mineral reserves currently in progress by SGS Canada Inc.”

The Met Tests were completed from a sample of 1250kg of drill core representative of the Barreiro deposit, which

is one of the nine deposits on the Company’s properties and the second being developed at the Project. The HLS

tests were conducted on the basis of a three-stage DMS processing production line (processing coarse, fine and

ultrafine materials), with a flowsheet similar to the DMS production line for the Xuxa deposit designed for the

Production Plant included in the Feasibility Study Report. HLS is only a perfect separation based on the minerals’

specific gravity (“ SG”). Thus, to evaluate DMS performance and separation efficiency in the real industrial

environment, DMS testwork will be conducted on the same sample in the upcoming months.

HLS test highlights:

 For 6.3mm and 10mm coarse size fractions, excellent lithium recoveries were achieved of 70.2 % and

66.1%, respectively, through gravity separation, wi thout the use of flotation or hazardous chemical

reagents, such as sulphuric acid, in the lithium concentration process. This is consistent with Sigma’s

intention to continue to process its lithium ore in a “green” environmentally-friendly and sustainable

manner, as mentioned above.

 The head grades of 1.37% and 1.44% Li2O for the samples selected for the 6.3mm and 10mm coarse

size fractions, respectively, are close to the 1.42% average grade for measured and indicated mineral

resources currently defined for the Barreiro deposit.

 Results are very similar to those for the Xuxa deposit in that a high purity concentrate was produced

with very low levels of alkalines (sodium oxide and potassium oxide) and iron oxide, which were all

well below 1%.

 The optimum feed size for the DMS ought to be between 6.3mm and 10.0mm, as shown in Chart 1

below, so as to maximize recovery while minimizing fines production, with feeds outside this range

achieving sub-optimal results, as indicated by the various curves plotted in the chart for each particle

size showing the Li2O grades versus the recoveries achieved.

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Table 1: HLS test results summary data for combined products:

Size of 6.3mm or less Weight

(%)

Assay (%) Distribution (%)

Li2O Fe2O3 K2O Na2O Li Fe2O3

Combined concentrate (2.82 SG) 16.1 6.00 0.65 0.64 0.39 70.2 46.3

Combined tailings (-2.65 SG) 70.2 0.39 0.06 2.90 4.63 20.0 19.2

Middling (-2.81 to +2.65 SG) 13.7 0.99 0.57 3.17 2.65 9.8 34.5

Head grade (plant feed grade) - 1.37 0.23 2.57 3.66 - -

Size of 10.0mm or less Weight

(%)

Assay (%) Distribution (%)

Li2O Fe2O3 K2O Na2O Li Fe2O3

Combined concentrate (2.81 SG) 15.9 6.00 0.55 0.60 0.57 66.1 38.9

Combined tailings (-2.65 SG) 67.6 0.43 0.07 3.28 4.78 20.1 21.9

Middling (-2.81 to +2.65 SG) 16.6 1.20 0.53 2.86 2.81 13.8 39.3

Head grade (plant feed grade) - 1.44 0.22 2.78 3.78 - -

Chart 1: Low sensitivity of recovery rate to particle size of the concentrate produced at 6% Li2O:

INDEPENDENT QUALIFIED PERSON

The technical and scientific information in this pr ess release has been reviewed and approved by Marc Antoine

Laporte, P.Geo., M. Sc., of SGS Canada Inc. Mr. Laporte is a Qualified Person as defined by National Instrument

43-101 and is independent of Sigma.

ABOUT SIGMA LITHIUM

Sigma is a Canadian company that has been producing environmentally sustainabl e battery-grade lithium

concentrate on a pilot scale since 2018 and shipping high-purity “green & sustainable” 6% Li2O battery-grade

lithium concentrate samples to some of the leading global cathode and battery producers of electric vehicles. The

company is in pre-construction (including the EPC and “contract-readiness” of core construction suppliers) of its

larger-scale lithium concentration commercial production pl ant. Based on the Feasibility Study Report, it will

contemplate a capacity to produce at the rate of 220,000 tonnes annually of battery-grade “green” lithium

concentrate and Sigma will be amongst the lowest-cost producers of lithium concentrate globally. The Feasibility

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6.00

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0.0 20.0 40.0 60.0 80.0 100.0

Li2O Grade (% )

Li Recovery (%)

Cumulative Sinks - Grade / Recovery Plot

(Stage Rec.)

-6.3 mm

-10 mm

-12.5 mm

-15.9 mm

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Study Report is being updated to include the developm ent of the Project’s second deposit, contemplating

production at the rate of 440,000 tonnes per annum (Phase 2 of the Project).

To secure a leading position supplying the clean mo bility and green energy storage value chain, Sigma has

adhered to the highest standards of environmental practices in line with its core values and mission since starting

activities in 2012. Sigma’s production process is powered by hydroelectricity and the Company utilizes state-of-

the-art dry-stacking tailings management and water-rec ycling techniques in its beneficiation process. Its

corporate mission is to execute its strategy while embracing strict ESG principles. Sigma’s shareholders include

some of the largest ESG-focused institutional investors in the world.

FOR ADDITIONAL INFORMATION PLEASE CONTACT

Sigma Lithium Resources Corporation

www.sigmalithiumresources.com

Company Contact:

Anna Hartley

Director of Investor Relations

(London) +44 7866 458 093

[email protected]

FORWARD-LOOKING STATEMENTS

This news release includes certain "forward-looking st atements" 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 nati onal 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 resour ces 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 an d 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 Serv ices 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.