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Ivanhoe Mines increases the size of massive Western Forelands copper discovery by 30% ■ Western Forelands ranks as the world’s largest and highest- grade copper discovery of the past decade ■ Western Forelands Indicated Mineral Resources now 42

Drill Results Resource Estimates Corporate Updates

September 8, 2026

Ivanhoe Mines increases the size of massive Western

Forelands copper discovery by 30%

Western Forelands ranks as the world’s largest and highest-

grade copper discovery of the past decade

Western Forelands Indicated Mineral Resources now 42

million tonnes at 2.66% copper, plus Inferred Mineral

Resources of 612 million tonnes at 1.80% copper (100% basis)

2026 Western Forelands 94,500-metre exploration drill

program is largest-ever

Size of Makoko District expected to grow as ongoing drill

results after March 31 not included in 2026 Mineral Resource

Ongoing drill program to be upsized in Q4 2026 to infill

shallow mineralization with potential for open pit extraction

Route to first production at Makoko to benefit from prior rapid

development of adjacent Kamoa-Kakula Copper Complex

Makoko scoping study to commence in Q1 2027

Project development expected to include multiple shallow

open pits, driving lower capex and much faster development

Ivanhoe’s track record of discovering high-grade copper in

the Western Forelands is the best in the world at a cost of

<$0.01 per pound of copper

Ivanhoe Mines to host Investor Webinar at 10:30am ET today

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KOLWEZI, DEMOCRATIC REPUBLIC OF CONGO – Ivanhoe Mines (TSX: IVN;

OTCQX: IVPAF) Executive Co-Chair Robert Friedland and President and Chief

Executive Officer Marna Cloete are excited to announce the updated Mineral

Resource estimate for the Makoko District, within Ivanhoe’s Western Forelands

Exploration Project in the Democratic Republic of the Congo (DRC).

The Western Forelands Exploration Project consists of a majority-owned licence

package covering 2,426 square kilometres, over six times larger than that of the

adjacent Kamoa-Kakula Copper Complex. Within the Western Forelands lies the

Makoko District, which is a series of genetically related world-class interconnected

copper discoveries.

The 2026 Mineral Resource for the Makoko District provides an update from the

last Mineral Resource, announced on May 14, 2025. Since then, approximately

64,000 metres of diamond drilling have increased the contained copper by 30% to

approximately 12 million tonnes. The 2026 Mineral Resource estimate uses

mineable shape optimization (MSO) to constrain the reported Mineral Resources,

unlike prior Makoko District estimates, which were reported directly from the block

model.

Watch a new video visualizing the Western Forelands’ 2026 Mineral

Resource update:

https://vimeo.com/1224774795/1777d26ac2

Ivanhoe Founder and Executive Co-Chairman Robert Friedland commented:

“The Western Forelands discoveries continue to grow explosively… confirming

the area as the most important sedimentary-hosted copper basin on our planet…

One might struggle to find a larger copper system that has been discovered in the

past 30 years. Ivanhoe’s world-leading geologists have so far found over 55

million tonnes of copper in the basin… and they are confident they will continue to

find additional world-class copper systems there for generations to come.

“Today’s interim update shows that the size of the Makoko District discovery

within the Western Forelands continues to grow, firmly ranking Makoko by far as

the world’s largest and the highest-grade new copper discovery of the past

decade… in an era when the desperate cries for new sources of copper are getting

louder and fewer copper discoveries are being made.

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“As the copper resource expands…so does our excitement and confidence. We

plan to intensify our efforts this year by, yet again, increasing the size of the in-fill

and step-out drilling program. Our subsequent Mineral Resource update will

include both additional metres and the projected 60,000 metres of drilling from this

year’s drill program that were not included in today’s update.

“Our track record of copper discovery in the Western Forelands is unrivaled… We

are discovering copper at an absurdly high discovery rate of 100 million pounds of

contained copper for every 1,000 metres drilled… and at an exceptionally low

discovery cost of a fraction of a penny per pound of high-grade copper

discovered. Our ability to find high-grade copper systems at such low cost is the

very definition of creating shareholder value.

“We plan for scoping study work to commence soon, which will include mining

some of the highest-grade, open pit copper mines in the world.”

Investor Webinar on Tuesday, September 8, 2026

Ivanhoe Mines will host an investor webinar today at 10:30 a.m. Eastern Time /

7:30 a.m. Pacific Time to discuss the updated Mineral Resource Estimate for the

Makoko District. The webinar will conclude with a question-and-answer (Q&A)

session.

To view the webinar, use the link:

https://meetings.lumiconnect.com/400-379-304-323

Participants Dial-in Numbers:

Local - Toronto: +1 (416) 855-9085

Toll Free - North America: +1 (800) 990-2777

Conference ID: 33298

An audio webcast recording of the webinar, together with supporting presentation

slides, will be available on Ivanhoe Mines’ website at www.ivanhoemines.com.

Following issuance, the updated Mineral Resource Estimate will be available at

www.ivanhoemines.com and at www.sedarplus.ca.

The Makoko District’s contained copper has grown significantly;

mineralization remains open in multiple directions for further resource

expansion.

The Makoko discovery, within the Western Forelands Exploration Project, was

made in 2018 when step-out drilling from Kakula intersected geologically identical

flat-lying, sedimentary-hosted copper mineralization west of the Kamoa-Kakula

joint venture. Subsequent drilling has discovered a continuously mineralized

region, now called the Makoko District, which encompasses the three discoveries

of Makoko, Makoko West, and Kitoko.

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The maiden Makoko Mineral Resource estimate was released on November 13,

2023, with a further Mineral Resource update, which included the adjacent Makoko

West and Kitoko discoveries, announced on May 14, 2025. Since the maiden

Mineral Resource of Makoko, the strike length of the Makoko District has

increased by over 400% to 16 kilometres and the total combined area has

increased by 300% to 61 square kilometres, as shown in Figure 1.

Mineralization of the Makoko District remains open to the northeast and downdip

of the current footprint, with potential for further resource expansion, as illustrated

in Figure 1.

Figure 1. The Makoko District’s 2026 Mineral Resource outline, overlaid with

copper grade.

Notes: Mineral Resource Data Source: The block model and resource outlines illustrated are based on the Mineral

Resource Estimate for the Makoko West and Kitoko, combined form the Makoko District.

Resources are reported separately in the text as Indicated and Inferred classifications and are visually distinguished on

the map by the 2026 Indicated (red outline) and 2026 Inferred (black outline) boundaries.

Mineral Resources that are not Mineral Reserves do not have demonstrated economic viability.

Inferred Mineral Resources have a lower level of geological confidence than Indicated Mineral Resources and may not

be converted to Mineral Reserves. It cannot be assumed that all or any part of an Inferred Mineral Resource will ever

be upgraded to a higher category.

Exploration Potential and "Open" Labels: The red arrows and annotations labelled "Open" indicate areas of prioritized

exploration potential outside the current defined 2026 Mineral Resource boundary. These areas are conceptual in

nature. There has been insufficient exploration drilling within these specific "Open" vectors to delineate them as

Mineral Resources, and it is uncertain whether further exploration drilling will result in these areas being converted to

Mineral Resources.

Drill holes highlighted on this map outside the Mineral Resource boundary include completed holes with final

laboratory assay results available as of March 31, 2026.

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Drilling is primarily vertical and broadly perpendicular to mineralization; therefore, true widths of copper mineralization

intersections are estimated to be 85% to 90% of the reported downhole drill lengths unless otherwise stated.

Analytical data has been verified using industry-standard QA/QC programs, including the insertion of certified

reference standards, blanks, and duplicates

The Western Forelands is by far the world’s largest copper discovery

of the past decade

In the 15 months between the 2025 Mineral Resource and the 2026 Mineral

Resource update, approximately 64,000 metres of drilling have been completed

across 106 holes. The drilling has added approximately 130,000 tonnes of

contained copper in the Indicated Mineral Resource category, an increase of 17%.

In addition, 2.63 million tonnes of contained copper have been added to the

Inferred category, an increase of 31%.

Makoko District’s Mineral Resources are now 34 million tonnes at 2.66% copper in

the Indicated category, plus 612 million tonnes at 1.80% copper in the Inferred

category. The Kiala deposit, which was discovered in 2020, remains unchanged at

8 million tonnes at 2.67% copper.

The Makoko District has higher-grade sub-zones that mirror the mineralization

style of the Kamoa orebody, which feeds the adjacent Kamoa-Kakula Copper

Complex’s Phase 3 concentrator and will feed the future Phase 4 concentrator.

The Western Foreland’s Makoko District and Kiala deposits, together rank as the

largest and highest-grade copper discovery of the past decade, as shown in

Figure 2.

Figure 2. The top 10 copper discoveries of the past decade, with the

Western Forelands ranking as the world’s largest and highest-grade.

Ivanhoe’s geologists have now discovered over 55 million tonnes (121

billion pounds) of contained copper in the Western Foreland shelf, including

Makoko District, Kiala, and Kamoa-Kakula Copper Complex.

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Source: Company filings, S&P Global Market Intelligence

Notes: Chart ranks new copper discoveries made since 2015 based on contained copper in resources, on a 100%

basis. Data source is S&P Global Market Intelligence article, dated August 27, 2026. Measured, Indicated and Inferred

Mineral Resources are separate categories and should not be added. Data source is the S&P Global Market

Intelligence article dated August 27, 2026. Mineral Resource estimates for the Western Forelands include the Makoko

District (Makoko, Makoko West and Kitoko) and Kiala at a 1.0% copper Western Forelands data has not been

reviewed by S&P Global. Discovery is defined by the date of the first drill hole in the past 10 years; resource figures

reflect the latest Mineral Resource estimate.

Ivanhoe’s geologists in the Western Forelands have achieved the

industry’s lowest cost of discovery and the greatest rate of delineating

contained high-grade copper

The total copper endowment discovered across the Western Forelands has been

at an industry-leading low cost of less than $10 per tonne of copper (<$0.005 per

pound of copper). London Metal Exchange (LME) copper prices have also

increased by 78% since the maiden Mineral Resource, from $8,167 per tonne on

November 13, 2023, to a high of $14,530 per tonne on September 7, 2026.

Figure 3. See below the world-leading growth of contained copper (million

tonnes) in the Western Forelands since the maiden Mineral Resource

estimate in 2023, against total drilling completed in the Western Forelands

since 2017 (kilometres). In just 2.5 years since the maiden Mineral Resource,

Ivanhoe’s geologists have significantly increased the contained copper in

Mineral Resources, while the copper price has also risen by 78%.

Notes: Resource updates are plotted on the cut-off date for drill & assay data.

(1) 2023 maiden Mineral Resource, September 3, 2023: Indicated Resources total 24 million tonnes at a grade of

3.29% copper, containing 0.8 million tonnes of copper at a 1% copper cut-off, and Inferred Resources total 243 million

tonnes at a grade of 1.7% copper, containing 4.17 million tonnes of copper at a 1% copper cut-off.

(2) 2025 Mineral Resource, December 31, 2026: Indicated Resources total 36 million tonnes at a grade of 2.76%

copper, containing 1.0 million tonnes of copper at a 1% copper cut-off, and Inferred Resources total 494 million tonnes

at a grade of 1.7% copper, containing 8.39 million tonnes of copper, at a 1% copper cut-off.

(3) 2026 Mineral Resource, March 31, 2026: Indicated Resources total 42 million tonnes at a grade of 2.66% copper,

containing 1.1 million tonnes of copper at a 1% copper cut-off, and Inferred Resources total 612 million tonnes at a

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grade of 1.8% copper, containing 11.02 million tonnes of copper, within mineable shapes, optimized at a 1% copper

cut-off.

Figure 4. Analysis of major copper discoveries made over the past 30 years.

The rate of copper discoveries made has been declining from approximately

10 per year between 20 and 30 years ago, to approximately one a year for

the past 10 years. Ivanhoe Mines has consistently been the world leader in

major copper discoveries.

Source: S&P Market Intelligence

(1) Oyu Tolgoi was not part of today’s version of Ivanhoe Mines Ltd. (IVN:TSX). On August 2, 2012, the old version of

Ivanhoe Mines was renamed to Turquoise Hill Resources, which was subsequently fully acquired by Rio Tinto on

December 16, 2022

Approximately 70% of the 2026 Makoko District diamond drilling

program is complete

The 2026 Western Forelands drilling program is Ivanhoe Mines’ largest to-date,

with more than 80,000 metres of diamond core drilling and 14,500 metres of

reserve circulation drilling planned.

The diamond drilling program is focused on three principal areas of the Makoko

District: step-out to the east and to the southwest, as well as infill drilling between

Makoko and Makoko West. Up to nine diamond drill rigs have been operating since

the start of the year. Approximately 70% of the 2026 diamond drilling program was

completed by August, with 55,700 meters drilled.

Approximately 20,000 metres of diamond drilling were completed in the first

quarter, the assays of which are included in the 2026 Mineral Resource update.

Results from the remaining 60,000 metres of 2026 diamond drilling program will be

included in a further Mineral Resource update in 2027.

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Highlights of the Makoko District 2026 Mineral Resource estimate

The updated 2026 Mineral Resource estimate for the Makoko District was prepared

by Ivanhoe Mines in accordance with the CIM 2014 Definition Standards for

Mineral Resources and Mineral Reserves.

■ Indicated Resources total 34 million tonnes at a grade of 2.66% copper,

containing 0.90 million tonnes (2.0 billion pounds) of copper at a 1% copper

cut-off. At a higher 1.5% copper cut-off, Indicated Resources contain a total

31.5 million tonnes at a grade of 2.77% copper, containing 0.87 million

tonnes (1.9 billion pounds) of copper.

■ Inferred Resources total 612 million tonnes at a grade of 1.8% copper,

containing 11.0 million tonnes (24.3 billion pounds) of copper, within

mineable shapes, optimized at a 1% copper cut-off.

The 2026 Western Forelands’ Mineral Resource estimate was prepared by Ivanhoe

Mines under the direction of Simon Bottoms, Executive Vice President of

Technical Services. Mr. Bottoms is the Qualified Person for the estimate and is not

considered independent of Ivanhoe for the purpose of NI 43-101. The 2026 Western

Forelands Mineral Resource estimate uses a data cut-off of March 31, 2026;

therefore drill results past this date have not been included.

2026 Mineral Resource estimate utilizes the mineable shape

optimization method for calculating contained copper

Prior Western Forelands Mineral Resource estimates were reported directly from

the block model after applying geological boundaries, grade estimates and cut-off

grades at the block level.

The 2026 Mineral Resource estimate applies, for the first time, the MSO method,

which applies practical underground mining geometries and constraints to the

underlying block model. MSO identifies coherent, potentially mineable shapes

based on parameters such as minimum mining width, stope dimensions and

orientation, mineralization continuity, and anticipated dilution. This approach

provides a more constrained representation of the tonnes and grades potentially

available for extraction by the assumed mining method, rather than assuming that

individual mineralized blocks above the cut-off grade can be selectively mined.

Ivanhoe Mines has discovered a total of approximately 34.8 million contained

tonnes (76.8 billion lbs.) of copper in Measured and Indicated Resources, and 17.1

million contained tonnes (37.8 billion lbs.) of copper in Inferred Resources across

the Western Forelands, at a 1.0% copper cut-off (on 100% project basis). This

incorporates the Mineral Resources of Kamoa-Kakula together with Makoko,

Makoko West, Kitoko (combined, called the Makoko District) and Kiala.