Rex Minerals : Quarterly Report - June 2022

Quarterly Activities Report

for the period ended 30 June 2022

ASX Release: 20 July 2022

Pushing for value

Rex Minerals Limited

ASX: RXM | OTCQB: RXRLF

ABN 12 124 960 523

Directors

Ian Smith, Non-Executive Chairman

Richard Laufmann, CEO & MD

Amber Rivamonte, CFO & Executive Director

Gregory Robinson, Non-Executive Director

Andrew Seaton, Non-Executive Director

Kay Donehue, Company Secretary

Ordinary Shares on Issue	592,654,254
Unquoted Options	20,246,667
Hog Ranch Consideration Rights 15,000,000
Share Price Activity - June 2022 Quarter
Low	12.5c
High	28.5c
Last	13.5c

Cash & cash equivalent $44.1M at 30 June 2022

T 1300 822 161 (Australia)

T [phone] (International)

PO Box 3435 Rundle Mall,

South Australia 5000

• [e-mail] W www.rexminerals.com.au

Operational Milestones

Hillside Copper-Gold Project, South Australia (100%)

• Ausenco's engineering and Owners' Team mine planning and infrastructure workstreams are advancing well
• As announced on 10 May 2022, Jason Schell has been appointed in the role of Executive General Manager, South Australia. Since joining, Jason's focus has been progression of all key operational work streams both with the Owners' Team and Ausenco
• The primary objective of Rex Minerals' operational and corporate team is to deliver a high-value mine development package for Hillside, capable of a Board-approved Financial Investment Decision (FID) by late CY2022
• The seismic survey (HiSeis) has now been processed and at depth the data shows what can be interpreted as a large intrusive body lying directly below the 2Mt copper Mineral Resource. This intrusive may represent the "source rock" for the Hillside deposit
• Based on the HiSeis work, a drill rig is now active and is designed to test geotechnical features that were identified in the survey so as to assist with mine planning.

Hog Ranch Gold Property, Nevada USA (100%)

• Exploration drilling, sampling and mapping continues for the 2022 field season
• Highlights from RC drill hole HR22-018 include1:
  o 147.83m @ 0.62g/t gold (Au) from surface (est true width ~104m) including 45.72m @ 1.06g/t gold from 44.2m (est true width ~32m).

Corporate

• Current cash & cash equivalent as at 30 June was $44.1M. The Company has sufficient funds to continue with its CY2022 workplans.

• Hog Ranch post Quarter Drilling Update (19 June 2022)

Quarterly Activities Report

Hillside Copper-Gold Project, South Australia

Engineering & Development

Effective 8 March 2022, Rex Minerals partnered with Ausenco for the provision of engineering services in relation to the Hillside Project.

In the past 10 years, Ausenco has delivered copper processing facilities and infrastructure into projects totalling US$7 billion globally. In Australia, Ausenco also successfully delivered the Carrapateena copper project in South Australia in 2020. This was the most recent large-scale greenfield copper concentrator installation in Australia.

The initial Ausenco work program is well underway and is covering detailed definition work to assess:

• process plant design and equipment selection, which will accommodate the base case 6Mtpa throughput levels with significant contingency to grow throughput and production rates
• the impact of recent macro developments and the consequence on supply chains, development and inflationary costs
• schedules which will then be updated
• the delivery of a project execution plan encompassing plant layout optimisation.

In parallel with this, the Company's experienced Owners' Team is finalising the mining schedules and non- process infrastructure as per the engineering, operational and funding timelines.

Figures 1 to 3 below illustrate the designed plant and mine layout in 2D and 3D renderings.

Process Plant

Rock Storage

Tailings Storage

Facility (TSF)

Open Pit

Figure 1: Hillside Copper-Gold Project - general layout

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Concentrate	Crushed Ore
Stockpile
Thickener

Filter	SAG Mill
Area

Flotation

Circuit

Reagents

Tailing

Thickeners

Figure 2: Hillside Copper-Gold Project - process plant general layout

Figure 3: Hillside Copper-Gold Project - upgraded jaw-gyratory crusher to allow future direct tip options

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Key Staff Appointments

As announced on 10 May 2022, Jason Schell has been appointed in the role of Executive General Manager, South Australia.

Jason is a senior executive with extensive operational expertise across a career spanning over 30 years in mining and mineral processing (copper-gold-silver-uranium). This experience more specifically includes the disciplines of hydrometallurgy, smelting, refining, steel manufacturing and large complex EPCM/EPC capital projects.

Since joining, Jason's focus has been progression of all key operational work streams both with the Owners' Team and Ausenco. The primary objective of the owner's operational and corporate team is to deliver a high-value mine development package capable of a Board-approved Financial Investment Decision (FID) by late CY2022.

Graham Teale has also joined the Rex team. Graham is well known to the South Australian geological community and his 45 years' experience in mineral exploration, mining and as a research geologist is unparalleled.

Graham has consulted to an extensive number of international and Australian-based mining companies which has seen him working in Indonesia, New Guinea, Fiji, Turkey, Sweden, USA, South Africa, Namibia, India and throughout Australia.

Graham has previously worked on Rex's Hillside Project and he was actively involved from late 2009 to 2013. He is responsible for initially identifying it as a key IOCG deposit.

3D Seismic Survey - Potential Project Implications

A 3D seismic survey has been completed at Hillside. The survey provides detailed geological and structural information over an area measuring 3km north-south, 2km east-west and to depths of over 2-3km centred directly over the large-scale Hillside deposit.

The initial review and interpretation of the survey data clearly validates the geological model that encompasses the current 2Mt copper Mineral Resource. The survey also identifies numerous interpreted faults in the host rocks which appear to control the higher-gradecopper-gold mineralisation, several of which extend well beyond current drilling limits.

At deeper levels (under the current drilling), the seismic data also shows what can be interpreted as a large intrusive body lying directly below the 2Mt copper Mineral Resource. Rex's geologists believe the interpreted body below the Hillside deposit may represent the "source rock" for the Hillside deposit. As detailed in the stylised image (see Figure 4), the Hillside Resource is interpreted to be what is termed a "Distal Skarn" deposited away from an intrusive heat source. The recent seismic work suggests that there may be deeper-seated features consistent with this well documented geological model. Figures 5 and 6 illustrate a cross-sectional and oblique view interpretation of the seismic data.

At the time of the announcement (see ASX Release of 7 June 2022), Rex's CEO and MD, Richard Laufmann, said: "We already know that structures control the high-grade copper zones at Hillside and now we can see a series of these structures radiating away from a large body at depth which we believe may be an intrusive. This could be the source of the copper at Hillside. This recent 3D seismic survey could be a game changer for Rex. We are very excited with what we are seeing in the new survey and what it may offer by way of upside for the project."

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Quarterly Activities Report

Figure 4: Generic model for base metals in Skarn deposits which are often found to be related to an intrusive host rock (such as a "Porphyry Stock"). This figure is modified after Sillitoe, R.H. 2010. Economic Geology 105 pages 3-41

Figure 5: Cross-section interpretation from the recent Hillside 3D seismic survey

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