Mr. Peter Akerley reports

ERDENE PROVIDES Q2 2026 BAYAN KHUNDII GOLD MINE UPDATE AND NOTICE OF CONFERENCE CALL AND WEBCAST

Erdene Resource Development Corp. has provided a Bayan Khundii gold mine production update for Q2 2026, operated by Erdene Mongol LLC (EM), the company's joint venture with Mongolian Mining Corp. (MMC). All dollars are U.S. dollars, unless otherwise noted.

Peter Akerley, Erdene's president and chief executive officer, stated: "Gold production of 11,709 ounces in Q2 was 37 per cent higher than the previous quarter, reflecting improved mining performance and continued strong operation of the process plant. In total, Bayan Khundii has produced 27,670 ounces of gold since first pour in September, 2025."

Mr. Akerley continued, "The average processed ore grade increased 25 per cent during the quarter, driven by improved ore control and mine-to-mill practices which significantly reduced dilution and ore loss."

Mr. Akerley concluded, "With performance at Bayan Khundii continuing to improve and exploration and technical studies advancing across our key projects, Erdene is well positioned to deliver value for shareholders."

Bayan Khundii gold mine -- Q2 2026 update

Bayan Khundii processed 153,000 tonnes of ore, averaging 1,682 tonnes per day, during the quarter ended June 30, 2026. The processed grade averaged 2.4 grams per tonne gold for the quarter ended June 30, 2026, a 25-per-cent increase compared with the quarter ended March 31, 2026, and quarterly gold recoveries averaged 96 per cent.

EM sold 11,709 ounces of gold and 3,317 ounces of silver at average prices of $4,493 per ounce gold and $72 per ounce silver, generating gross revenues of $53-million ($75-million (Canadian)) during the quarter ended June 30, 2026.

Outlook

EM's focus for the balance of 2026 is on continued optimization of mining operations. Precision mining, blasting, stockpile management, crushing improvements and processing throughput increases are aimed at reaching production consistent with projections noted in the 2023 feasibility study.

Q2 2026 conference call details

Erdene will release its unaudited financial and operating results for the three months ended June 30, 2026, on Friday, Aug. 14, 2026, after market close. The company will host a conference call and webcast to discuss the results on Monday, Aug. 17, 2026, commencing at 10 a.m. Eastern Time. The webcast will be accessible on-line.

A replay of the webcast will be available on-line for one year after the event.

The dial-in numbers for the conference call are as follows.

North America (toll-free):  1-800-717-1738

Overseas or local (Toronto):  1-289-514-5100

Qualified person

Jon Lyons, FAusIMM, chief development officer for Erdene, is the qualified person as that term is defined in National Instrument 43-101 and has reviewed and approved the technical information contained in this news release.

About Erdene Resource Development Corp.

Erdene Resource Development is a Canada-based resource company producing gold at the high-grade, low-cost Bayan Khundii gold mine in underexplored and highly prospective Mongolia. The company has interests in a highly prospective portfolio of precious and base metal projects in close proximity to the Bayan Khundii gold mine in the Khundii Minerals district, which provides a robust organic growth pipeline. Erdene Resource Development is listed on the Toronto Stock Exchange (symbol: ERD), the Mongolian Stock Exchange (symbol: ERDN) and the OTCQX market (symbol: ERDCF).

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