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Metallurgical Testwork and Preliminary Economic Assessment Update

Economic Studies Metallurgy & Processing

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TSX-V News Release ASX News Release

27 February 2026 28 February 2026

Metallurgical Testwork and Preliminary Economic Assessment Update

Resouro Strategic Metals Inc. (ASX: RAU; TSX-V: RSM; FSE: 8TX; OTCQB: RSGOF) (“Resouro” or the

“Company”) provides an update on ongoing metallurgical testwork and advancement of the Preliminary

Economic Assessment (“PEA”) for its Tiros Titanium and Rare Earths Project (“Tiros” or “Tiros Project” or

the “Project”) located in Minas Gerais, Brazil.

Metallurgical testwork completed to date highlights that a conventional process flowsheet can produce a

titanium dioxide (“TiO2”) concentrate and achieve high Total Rare Earth Oxide (“TREO”) extractions

using Sulphuric Acid Leach (SAL).

Highlights of the results include:

Fine particle flow sheet (< 20 micron) using sulphuric acid;

• 88.8% to 95.2% stage extraction of TREO; and

• 71.2% to 94.2% of TiO2 stage recovery.

Coarse particle flow sheet (>75 micron) using conventional flowsheet;

• 76.8% TiO2 concentrate grade; and

• TiO2 stage recovery of coarse feed 39%.

Important notice: These results must be read along with Appendix I (Details of Results) and Appendix II

(JORC Table).

Commenting on the latest results and update for Tiros, Christopher Eager, Resouro’s CEO, said;

“Resouro is well advanced in testing a conventional process flowsheet for recovery of titanium dioxide to

concentrate and high leach extractions of rare earth elements. The latest metallurgical testwork results

provide increasing confidence that the Tiros Project has the potential to be developed into a globally

significant regolith (highly weathered soft rock) type titanium and rare earths project. ”

Resouro Strategic Metals Inc.

BC0430203 (Canada) ARBN 671 716 457 (Australia)

Suite 250, 997 Seymour Street, Vancouver, British Columbia, Canada V6B 3M1 – Tel: +1 403 807 2948

Level 10, Kyle House, 27-31 Macquarie Place, Sydney NSW 2000 – Tel: + 61 407 123 143

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Ongoing metallurgical testwork and optimization

The current phase of the metallurgical testwork, being conducted at SGS Lakefield (Canada), and at CIT

Senai and SGS Geosol, (Brazil), is focused on reducing sulphuric acid consumption and further optimizing

recoveries.

Preliminary sulphuric acid consumption ranged from 700kg/t to 1,320kg/t. These acid consumption figures

are for raw sample minus 20 micron fraction prior to beneficiation activities and before sulphuric acid

recycling. The minus 20 micron sample makes up about 56% of the raw sample weight and therefore

equates to 392kg/t to 739kg/t of acid per tonne of raw sample.

Iron oxides and alumina make up approximately 54% of the minus 20 micron feed and are significant

consumers of acid. Beneficiation testwork is aimed at reducing iron oxide and alumina and other worthless

gangue minerals from the leach feed. Beneficiation is intended to decrease the volume of material to be

leached by reducing low value acid consuming minerals, increasing the TiO2 and TREO grades of the leach

feed, with the aim of improving overall project economics.

Ongoing work is evaluating:

• Magnetic separation to remove iron oxides which are significant acid consumers;

• Flotation to remove non-valuable silicate and gangue materials prior to leaching;

• Optimization of reductive calcination and acid bake conditions;

• Acid regeneration and acid recycling; and

• Potential on-site sulphuric acid production to reduce operating costs.

Initial testwork on magnetic and electrostatic separation and flotation have been encouraging, indicating

potential to materially reduce acid consumption while maintaining high metal recoveries.

Resouro will also investigate acid regeneration and recycling and the feasibility of producing sulphuric acid

at site to take advantage of abundant elemental sulphur and sulphur mineralizations available in Brazil.

Preliminary economic assessment update

The PEA continues to advance, however, to be more economical and respectful of budgets, consideration

is being given to placing the PEA on hold pending completion of ongoing metallurgical testwork

optimization. The key milestones achieved or in progress include:

• Initial mine planning substantially completed pending final processing cost inputs;

• Environmental Impact Assessment and Project permit process advancing;

• Infrastructure, processing plant capital and operating costs to be finalized following completion of

beneficiation, the current stage of metallurgical testwork; and

• Initial independent TiO2 and rare earth oxides market study received; update to follow completion

of beneficiation.

Finalization of processing cost inputs remains the key workstream prior to completion of the PEA.

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This announcement has been authorized for release by the Chief Executive Ojicer of Resouro Strategic

Metals Inc.

For further information, please contact:

Christopher Eager,

Chief Executive Officer

[email protected]

+44 7388 0579809

About Resouro

Resouro is a Canadian incorporated mineral exploration and development company, listed on the ASX, TSXV, OTC,

and FSE, focused on the discovery and advancement of economic mineral projects in Brazil, including the Tiros

Titanium-Rare Earths Project and the Novo Mundo Gold Project. The Tiros project has 28 mineral concessions totaling

497 km2 located in the state of Minas Gerais, one of the best infrastructurally developed states of Brazil, 350 km from

the state capital of Belo Horizonte. Resouro's Mineral Resource Estimate for the Tiros Project contains 165 million

tonnes of titanium dioxide and 5.5 million tonnes of total rare earths oxides within a Measured and Indicated Resource

of 1.4 billion tonnes.

Note: Further details of the Company’s JORC MRE are contained within the Company’s ASX announcement of 9 April,

2025/TSX-V 8 April 2025. Resouro is not aware of any new information or data that materially aLects the information

included in the Company’s announcement and that all material assumptions and technical parameters underpinning

the estimates referred to therein continue to apply and have not materially changed.

Qualified Person Statement

The scientific and technical information in this news release relating to metallurgical testwork and preliminary

economic study inputs for the Tiros Project has been reviewed and approved by Mr Richard Wagner, P.Eng., a

Qualified Person as defined under National Instrument 43-101 – Standards of Disclosure for Mineral Projects. Mr

Wagner is an independent Qualified Person within the meaning of National Instrument 43-101.The Qualified Person

has verified the metallurgical testwork results from laboratories including SGS Lakefield (Canada), CIT Senai and SGS

Geosol (Brazil).

Category Million To nn e TiO2 % TREO (ppm) MREO (ppm)

REO/TREO rat

Measured

30

24

9,300

2,500

27%

Indicated

74

23

8,900

2,300

26%

M + I 103 23 9,100 2,400

26%

Inferred

33

22

8,300

2,200

26%

Measured

340

11

3,700

1,000

28%

Indicated

930

11

3,600

1,000

28%

M + I 1,300 11 3,600 1,000

28%

Inferred

470

11

3,400

920

27%

Measured

367

12

4,100

1,100

28%

Indicated

1,000

12

4,000

1,100

27%

M + I 1,400 12 4,000 1,100

28%

Inferred

500

12

3,700

1,000

27%

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Forward-Looking Information

This news release contains certain "forward-looking information" within the meaning of applicable securities law.

Forward-looking information is frequently characterized by words such as "plan" , "expect" , "project" , "intend" ,

"believe" , "anticipate" , "estimate" and other similar words, or statements that certain events or conditions "may" or

"will" occur. Although we believe that the expectations reflected in the forward-looking information are reasonable,

there can be no assurance that such expectations will prove to be correct. We cannot guarantee future results,

performance or achievements. Consequently, there is no representation that the actual results achieved will be

the same, in whole or in part, as those set out in the forward-looking information.

Forward-looking information is based on the opinions and estimates of management at the date the statements are

made and are subject to a variety of risks and uncertainties and other factors that could cause actual events or results

to dider materially from those anticipated in the forward- looking information. Some of the risks and other factors that

could cause the results to dider materially from those expressed in the forward-looking information include, but are

not limited to: general economic conditions in Canada and globally; industry conditions, including governmental

regulation and environmental regulation; failure to obtain industry partner and other third party consents and

approvals, if and when required; the need to obtain required approvals from regulatory authorities; stock market

volatility; liabilities inherent in the mining industry; competition for, among other things, skilled personnel and

supplies; incorrect assessments of the value of acquisitions; geological, technical, processing and transportation

problems; changes in tax laws and incentive programs; failure to realize the anticipated benefits of acquisitions

and dispositions; and the other factors. Readers are cautioned that this list of risk factors should not be construed as

exhaustive.

The forward-looking information contained in this news release is expressly qualified by this cautionary statement.

We undertake no duty to update any of the forward-looking information to conform such information to actual results

or to changes in our expectations except as otherwise required by applicable securities legislation. Readers are

cautioned not to place undue reliance on forward-looking information.

Neither the ASX, OTC, 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 release.

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Appendix I – Detailed metallurgical testwork results.

Resouro Strategic Metals (Resouro) is advancing the metallurgical process development with testwork on

samples from the Tiros Titanium and Rare Earths deposit, Minas Gerais, Brazil. Metallurgical testwork is

being conducted in Brazil at CIT Senai and SGS Geosol (Belo Horizonte, Minas Gerais) and in Canada at

SGS Lakefield (Lakefield, Ontario).

Metallurgical testwork is aimed at refining and optimizing the conceptual Tiros process flowsheet (Figure1

as previously described in Resouro news release 26 November 2025). Recent metallurgical work has

concentrated on enhancing recovery of rare earths and titanium from the fines part of the flowsheet

circuit, comprising material finer than 75 micron.

Metallurgical testwork described here was conducted using the BK 09 sample, with head assays results

indicated in Table 1. The BK 09 sample was derived from drill holes within the Central Zone of the Tiros

deposit. The drill holes used in the BK 09 composite sample are indicated in Figure 2.

Figure 1 - Conceptual Tiros process flowsheet

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Figure 2 – Location of samples

Location of samples used in BK 09 samples used in this phase of the testwork are shown as yellow circles.

The proposed future high-grade mining starter pits are indicated here in green.

Coarse particle flowsheet development

Work on the coarse particle flowsheet development was carried out at CIT Senai. Testwork on the +75

micron fraction, representing approximately 25.8% of the mass deportment, demonstrated that a coarse

titanium oxide product (mineral anatase) can be recovered.

The objective of this phase of testwork was to recover a coarse TiO2 product suitable for the traditional

TiO2 market. This testwork realized a concentrate grading 76.8% TiO2 at 39% unit stage recovery and 10.6%

overall recovery. The overall testwork results are summarized below in Table 1. The coarse particle

metallurgical flowsheet established in this phase of the testwork includes magnetic separation, gravity

separation, calcination and acid scrubbing.

Table 1 – Overall summary of metallurgical results - coarse particle +75 micron size results

Overall summary of coarse particle metallurgical results on sample BK 09 (+75 micron material)

TiO2 (%) TREO (ppm) Al2O3 (%) Fe2O3 (%) SiO2 (%)

100.0% 16.2% 5019 11.3% 34.4% 28.0%

>75µm 25.8% 17.1% 3250 3.4% 42.3% 30.8%

<75µm 74.2% 15.9% 5600 14.0% 31.6% 27.0%

<20µm (calc.) 55.7%

Final Concentrate Grade 2.2% 76.8%

Overall Recovery 10.6%

Unit Recovery of >75µm 39.0%

AssaysWeight (%)

Head Grade (BK-09)

Weight Split

Recovery to

the coarse

separation

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Fines particle flowsheet development

Testwork on the fine particle size flowsheet is currently underway at SGS Lakefield (Canada) and at CIT

Senai (Brazil).

This fine particle phase of the testwork is focused on leaching rare earths from the minus 20 micron

particles, which represents approximately 56% of the overall weight in the feed. The flowsheet being

tested includes process steps of magnetic separation, reductive calcination (at 600oC), and acid baking

(at 280oC) using sulphuric acid. Results to date demonstrate that the rare earths and a significant

proportion of the TiO2 can be successfully leached under these conditions. The best TiO2 recovery

achieved was 94.2% (range71.2% to 94.2%), based on a minus 20 micron feed for the stream being

processed in this testwork. The best TREO recovery achieved was 95.2% (range 88.8% to 95.2%) for this

stream.

A summary of these results is presented in Table 2.

Table 2 – Fine particle minus 20 micron size results *

Summary of the key fine particle leach testwork on sample BK 09, 20 micron material

* acid consumption numbers are for the < 20 micron sample weight tested which was about 56% of the raw feed sample weight

The ongoing testwork program is focused on maximizing recoveries while minimizing acid consumption.

Key components of the current testwork program include:

• Use of the higher-grade composite sample BK 19, which is most representative, for the future mine

plan, with that sample taken from drilling from within the proposed initial mine plan pits (location

of these pits indicated in green in Figure 2 above).

• Optimization of magnetic separation conditions to remove iron oxides which are significant acid

consumers.

• Inclusion of a flotation stage to remove non valuable waste material prior to leaching, thereby

reducing the total acid consumption.

• Determination of reductive calcination conditions and a second subsequent stage of magnetic

separation prior to the acid bake metal recovery.

• Optimization of the acid bake TiO2 and REO leach conditions.

• Evaluation of REO and fine TiO2 product precipitation after leaching.

• Assessment of sulphuric acid re-circulation and regeneration.

• Study of acid neutralization.

TiO2 TREO Al2O3 Fe2O3 SiO2

1.50 1.32 94.2% 95.2% 93.9% 88.6% 25.0%

1.30 1.00 89.8% 92.6% 87.5% 87.6% 16.6%

1.10 0.95 71.2% 88.8% 75.3% 86.3% 17.0%

Unit Recovery (%)H2SO4/Rock

kg/kg added

H2SO4/Rock

kg/kg consumed

H2SO4/Feed

kg/kg added

H2SO4/Feed

kg/kg consumed

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JORC Code, 2012 Edition – Table 1 Report

TIROS REE + Ti PROJECT – PRELIMINARY METALLURGICAL TESTWORK DISCLOSURE

Section 1 – Sampling Techniques and Data

(Criteria in this section apply to all succeeding sections.)

Criteria JORC Code Explanation Commentary

Sampling

techniques

• Nature and quality of sampling (eg cut channels, random

chips, or specific specialized industry standard

measurement tools appropriate to the minerals under

investigation, such as down hole gamma sondes, or

handheld XRF instruments, etc). These examples should

not be taken as limiting the broad meaning of sampling.

• Include reference to measures taken to ensure sample

representativity and the appropriate calibration of any

measurement tools or systems used.

• Aspects of the determination of mineralisation that are

Material to the Public Report. In cases where industry

standard’ work has been done this would be relatively

simple (eg ‘reverse circulation drilling was used to obtain

1 m samples from which 3 kg was pulverised to produce a

30 g charge for fire assay’). In other cases, more

explanation may be required, such as where there is

coarse gold that has inherent sampling problems.

Unusual commodities or mineralisation types (eg

submarine nodules) may warrant disclosure of detailed

information.

• Two samples were used for the results of this press release:

• BK-09 – Representative of the SOX portion of the

deposit, the more intense oxidized bed lying at the

top of the mineralized package. This bed contains

the high-grade zone, but this sample is not

restricted to this zone. Coarse laboratory rejects

from Air Core (“AC”) and diamond drilling were

randomly selected from the drilling at the Tiros

Central block, assuring that the compound grade is

similar to the average grade of this zone.

• BK-19 – Representative of the high-grade zone,

occurring at the SOX bed and located within the

expected final pit. AC and diamond drilling samples

were used, from holes selected in order to

represent all pits being planned. Half core was

selected for the diamond drilling samples selected.

The AC samples were split with a Jones splitter to

obtain about 3 kg of representative material per

meter. The weighted average was similar to the

expected assay.