Resource Base : RBX Expands Footprint at Potential REE Project Mitre Hill

onlyLevel 4, 105 St Georges Terrace Perth WA 6000

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useEx cutive Chairman & CEO Shannon Green

Non-Executive Director

Jamie Myers

Non-Executive Director

Paul Hissey

personalCFO & Company Secretary Ailsa Osborne

ASX: RBX

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Company Secretary

Ailsa Osborne

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3 March 2022

RBX Expands Footprint at Potential REE Project

Mitre Hill

Highlights

• Twelve (12) Exploration Licence applications totalling 1,140km2 submitted for tenements prospective for Ionic Clay Rare Earths in Victoria, expanding the Mitre Hill project footprint to 2,649km2
• RBX 100% owned Mitre Hill project will become the 2nd largest land position in the southern margin of the Murray Basin an emerging Rare Earths precinct
• Mitre Hill Ionic Clay Rare Earth project situated adjacent to Australian Rare Earths' (ASX:AR3) JORC 2021 Inferred Mineral Resource of 39.9Mt @ 725ppm Total Rare Earth Oxide (TREO)1,2
• RBX on track to commence drilling on EL007646 this month

Resource Base Limited (ASX:RBX) (Resource Base or the Company) is pleased to announce that it has submitted Twelve (12) Exploration Licence applications totalling 1,140km2 submitted for tenements prospective for Ionic Clay Rare Earths (REE) in Victoria.

With the Mitre Hill project growing significantly to 2,649km2 the Company believes it will hold the 2nd largest land position in the southern margin of the Murray Basin that is prospective for REE provided all applications are granted.

Figure 1: Regional setting of Mitre Hill Project tenements in emerging Rare Earths precinct.

1. Refer Australian Rare Earths' (ASX:AR3) Prospectus dated 7 May 2021.
2. These results do not guarantee the same or similar levels of success on the Mitre Hill Project tenements

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The Mitre Hill tenements encompass 2,649km2 in the emerging Ionic Clay Rare Earth precinct across south-eastern South Australia and western Victoria. With two (2) of the new applications located approximately 25km east from AR3 most recent drilling in the north containing drilling intercepts >500ppm TREO (refer Figure 2 below).

Figure 2: Map showing Mitre Hill, AR3 and Savic tenement areas, overlaid with drilling on tenements held by AR33 and Savic4.

1. Refer Australian Rare Earths' (ASX:AR3) Prospectus dated 7 May 2021 and announcement on 19 January 2022 "Recent Drilling Confirms Significant Regional Prospectivity of Koppamurra" for AR3 drill hole data.
2. Refer TSX Venture Exchange (TSXV) listed company Lions Bay Capital Inc (TSXV: LBI) announcement on 20 January 2022 "Lions Bay Capital Inc. provides an Update on Savic Exploration" for Savic drill hole data.

RESOURCE BASE LIMITED ACN 113 385 425

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Regional exploration by AR3 has confirmed Ionic Clay Rare Earth mineralisation extends at least 40km north of the existing Red Tail and Yellow Tail mineral resource area5 and recent exploration undertaken by Lions Bay on the exploration licences (ELs) held by Savic Minerals Pty Ltd (Savic)6 shows further support for the Company's opinion that there is a potentially significant regional scale Ionic Clay Rare Earths precinct emerging in the southern margin of the Murray Basin.

Figure 3 below shows the proximity of existing and new RBX tenement applications to AR3's red and Yellow Tail Ionic Clay Rare Earths resources.

Figure 3: Map showing Mitre Hill, AR3 and Savic tenement areas, overlaid with drilling on tenements held by AR37 and Savic8 with reference to the 5 applications adjacent to Savic drilling.

1. Australian Rare Earths' (ASX:AR3) announcement 25 November 2021 "Initial Assays Confirm the Regional Prospectivity of Koppamurra Project"
2. TSX Venture Exchange (TSXV) listed company Lions Bay Capital Inc (TSXV: LBI) announced on 20 January 2022 "Lions Bay Capital Inc. provides an Update on Savic Exploration".
3. Refer Australian Rare Earths' (ASX:AR3) Prospectus dated 7 May 2021 and announcement on 19 January 2022 "Recent Drilling Confirms Significant Regional Prospectivity of Koppamurra" for AR3 drill hole data.
4. Refer TSX Venture Exchange (TSXV) listed company Lions Bay Capital Inc (TSXV: LBI) announcement on 20 January 2022 "Lions Bay Capital Inc. provides an Update on Savic Exploration" for Savic drill hole data.

RESOURCE BASE LIMITED ACN 113 385 425

Suite 4.01, Level 4, 105 St Georges Terrace, Perth WA 6000

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www.resourcebase.com.au

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RBX currently has sixteen (16) tenements, fifteen (15) applications and one (1) granted tenement the southern margin of the Murray Basin in western Victoria and one (1) application in south-eastern South Australia. The areas targeted by these applications are considered by the Company to have significant potential to host Ionic Clay Rare Earth mineralisation.

The Company has a significant land holding in the southern margin of the Murray Basin and believes it is very well positioned to play a key role in the emerging Iconic Clay Rare Earths precinct that is potentially of global significance.

New Exploration Licence Application Details submitted in Victoria

Victoria Tenements

Application Date

Tenement Size (km2)

EL007888

8 Feb 2022

6

EL007889

8 Feb 2022

15

EL007891

8 Feb 2022

6

EL007892

8 Feb 2022

4

EL007893

8 Feb 2022

9

EL007894

8 Feb 2022

6

EL007895

8 Feb 2022

13

EL007896

8 Feb 2022

24

EL007897

8 Feb 2022

44

EL007898

8 Feb 2022

204

EL007899

8 Feb 2022

353

EL007900

8 Feb 2022

456

- ENDS -

This announcement has been authorised by the Board of Resource Base Limited. For further information please visit our website - www.resourcesbase.com.au

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RESOURCE BASE LIMITED ACN 113 385 425

Suite 4.01, Level 4, 105 St Georges Terrace, Perth WA 6000

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About Resource Base Ltd

Resource Base Ltd (ASX:RBX) is an Australian based mineral exploration company focused on the development of highly prospective exploration projects with demonstrated potential for scalable discoveries.

Black Range Project

The Black Range Project (124km2) in Victoria's premier porphyry and VHMS target district, the Mount Stavely Volcanic Complex (MSVC) in Western Victoria, captures three fault-bound segments of the MSVC volcanics with a combined strike length of approximately 55kms. The Project includes the advanced Eclipse prospect, which is prospective for copper, gold and zinc.

The MSVC is considered an analogue of the Mt Read Volcanics in Tasmania, which is host to a number of world-class VHMS deposits (Rosebery, Hellyer, Que River), the giant Mt Lyell Cu-Au deposit, and the Henty Au deposit. Numerous other targets, including Anomaly F, Honeysuckle, Anomaly K and Mt Bepcha are associated with MSVC rocks across the tenement but have seen little work to date.

Petrological studies indicate that important VHMS style hydrothermal alteration and is well developed on the Eclipse prospect. Resource Base will utilise systematic geophysics, drilling and geochemical analyses combined with petrological and hyperspectral SWIR alteration mapping to vector towards zones with high mineralisation potential as identified from comparison with known VHMS deposits in the Mt Read Volcanics and around the world.

Mitre Hill Project

The Mitre Hill tenements account for 2,649km2 that are prospective for ionic clay hosted Rare Earth Elements (REE) within the southern margin of the Murray Basin, the Project consists of one (1) granted tenement and fifteen (15) applications in Victoria and one (1) application in South Australia.

Upon granting of all tenements Mitre Hill will hold the 2nd largest position within a potential emerging Ionic Clay Rare Earth precinct located in the southern margin of the Murray Basin across Victoria and South Australia.

The licence and applications are located in the southern margin of the Murray Basin on the South Australian and Victorian state Border near the towns of Naracoorte, Penola and Edenhope. The largest and most prospective Application, ELA 2021/00059, runs approximately in a line, covering over 40km of strike length, from the towns of Naracoorte and Penola in South Australia.

The main economic target is ionic clay hosted REE deposits, with possible economic concentrations of Heavy Rare Earths considered strategically important given global supply modelling. The Applications are located over the transition from the concluding phases of the Loxton - Parilla strandlines to the more broadly spaced Bridgewater formation in South Australia and Victoria. A significant archive of historical exploration data has been acquired by the Company, including drilling results, numerous government studies and minor private exploration.

RESOURCE BASE LIMITED ACN 113 385 425

Suite 4.01, Level 4, 105 St Georges Terrace, Perth WA 6000

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