Regulus Resources Inc. Achieves Promising Results in Copper Extraction

Vancouver, British Columbia, May 20, 2025 — Regulus Resources Inc., a Canadian exploration company specializing in metals and mining, has announced significant progress in its copper extraction efforts. The company, which focuses on copper and gold projects in South America, particularly in Peru, Argentina, and Chile, has reported attractive copper extraction rates using Nuton Bio-Leaching technology.

Innovative Bio-Leaching Technology

Regulus is collaborating with Nuton LLC, a venture of Rio Tinto, to evaluate Nuton’s proprietary sulphide bio-leaching technologies at the AntaKori project. The Phase Two metallurgical test program builds on the success of the Phase One program, which confirmed that AntaKori material is suitable for Nuton’s bio-leaching technology. This innovative approach is particularly effective for enargite-rich high-sulphidation mineralization, which constitutes a significant portion of the mineralization at the AntaKori project.

Phase Two Program Updates

In the ongoing Phase Two program, Regulus is testing a variety of conditions to determine the optimal setup for leaching AntaKori mineralization. The company has reported progress on four test columns, with three focused on optimizing the bio-leaching process. These tests are crucial for enhancing the efficiency and effectiveness of copper extraction, potentially leading to more sustainable and cost-effective mining operations.

Integrated Sulphide Project Resource Estimate

In addition to the bio-leaching advancements, Regulus is also providing an update on the integrated resource estimate for the Coimolache Sulphide/AntaKori copper-gold project. This project, in collaboration with Compañía Minera Coimolache S.A., aims to evaluate the integrated resource potential, further solidifying Regulus’s commitment to expanding its exploration and development activities in South America.

Market Context

As of May 15, 2025, Regulus Resources Inc. is trading at a close price of 1.98 CAD on the TSX Venture Exchange, with a market capitalization of 242.62 million CAD. Despite a negative price-to-earnings ratio of -61.17, the company’s recent developments in bio-leaching technology and resource estimation may positively influence investor sentiment.

Regulus Resources Inc. continues to prioritize its exploration activities in Argentina, focusing on the Rio Grande porphyry system. For more information about the company and its projects, visit www.regulusresources.com .

This news highlights Regulus Resources Inc.’s innovative approach to copper extraction and its ongoing efforts to enhance resource evaluation, positioning the company as a key player in the metals and mining sector.