Mr. Neil Woodyer reports

ARIS MINING TO JOIN THE S&P/TSX COMPOSITE INDEX

As disclosed by S&P Dow Jones Indices on Sept. 5, 2025, Aris Mining Corp.'s common shares will be added to the S&P/TSX Composite Index prior to the open of trading on Monday, Sept. 22, 2025.

The S&P/TSX Composite Index is Canada's premier equity benchmark and includes the largest and most actively traded companies on the Toronto Stock Exchange.

Neil Woodyer, chief executive officer, commented: "Our inclusion in the S&P/TSX Composite Index underscores the strong momentum under way at Aris Mining. This milestone highlights the value we are creating for shareholders and positions us among Canada's most established public companies. With gold production ramping up at Segovia following the commissioning of the second mill and construction advancing at the Marmato bulk mining zone, we remain focused on doubling our annual gold production to more than 500,000 ounces while advancing the Soto Norte and Toroparu projects -- catalysts that support our longer-term growth and our vision to create a leading gold mining company in Latin America."

About Aris Mining Corp.

Founded in September, 2022, Aris Mining was established with a vision to build a leading Latin America-focused gold mining company. The company's strategy blends current production and cash flow generation with transformational growth driven by expansions of the company's operating assets, exploration and development projects. Aris Mining intends to unlock value through scale and diversification. The company is listed on the Toronto Stock Exchange (ARIS) and the NYSE-American (ARMN), and is led by an experienced team with a record of value creation, operational excellence, financial discipline and good corporate governance in the gold mining industry.

Aris Mining operates two underground gold mines in Colombia: the Segovia operations and the Marmato complex, which together produced 210,955 ounces of gold in 2024. With expansions under way, Aris Mining is targeting an annual production rate of more than 500,000 ounces of gold, following the commissioning of the second mill at Segovia, completed in June and ramping up during H2 2025, and the construction of the bulk mining zone at the Marmato complex, expected to start ramping up production in H2 2026. In addition, Aris Mining operates the 51-per-cent-owned Soto Norte joint venture, where a PFS study is complete on a new, smaller-scale development plan which confirms Soto Norte as a high-quality, long-life project with robust economics and industry-leading environmental and social design features. In Guyana, Aris Mining owns the Toroparu gold/copper project, where a new preliminary economic assessment (PEA) is under way.

Colombia is rich in high-grade gold deposits and Aris Mining is actively pursuing partnerships with the country's dynamic small-scale mining sector. With these partnerships, the company enables safe, legal and environmentally responsible operations that benefit both local communities and the industry.

Qualified person

Pamela De Mark, PGeo, senior vice-president of geology and exploration of Aris Mining, is a qualified person as defined by National Instrument 43-101, and has reviewed and approved the technical information contained in this news release.

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