Horizon Copper Corp. has highlighted new high-grade assay results from drilling at the Hugo North Extension (HNE) deposit, part of the Oyu Tolgoi copper-gold project in Mongolia. The results, disclosed by Entrée Resources Ltd., are from drilling programs conducted between 2022 and 2024.

The latest assays, released by Oyu Tolgoi LLC (OTLLC), a joint venture partner of Entrée, expand on results previously announced in February 2024 and February 2025. The data includes six diamond drill holes — five drilled underground in 2024 and one from 2022 — along with a surface diamond drill hole completed in 2024.

The surface hole was drilled on the Entrée/Oyu Tolgoi Joint Venture Property (JV Property), while the underground holes were collared from existing infrastructure on the Oyu Tolgoi mining license. All holes were drilled at moderate dips directed north or northeast, targeting the mineralized zones within or near the projected Lift 2 block cave area. Several holes intersected strong copper and gold mineralization extending up to 200 meters beneath the base of the proposed Lift 2.

Erfan Kazemi, president and CEO of Horizon Copper, expressed optimism about the findings.

“These results from the Hugo North Extension continue to rank among the most impressive globally for copper projects,” Kazemi said. “They reinforce the long-term potential of the Lift 2 area. As Entrée’s largest shareholder, Horizon is confident that our stake will generate significant long-term value and cash flow for our shareholders.”

Highlighted HNE Drill Results:

Underground Drill Holes

•             UGD871: 197 meters grading 1.07% copper and 0.38 grams per tonne (g/t) gold from 358 meters, including 89 meters at 1.33% copper and 0.44 g/t gold.

•             UGD873A: 279 meters at 1.12% copper and 0.16 g/t gold from 360 meters.

•             UGD876: 169.3 meters at 2.72% copper and 0.82 g/t gold from 224.7 meters, including 112 meters at 3.33% copper and 0.81 g/t gold.

Surface Drill Hole

•             UGD189B: 552 meters at 2.30% copper and 1.45 g/t gold from 1,226 meters, including 260 meters at 3.29% copper and 2.08 g/t gold.

In April 2025, project operator Rio Tinto Group confirmed that ramp-up of the Lift 1 underground mine remains on schedule. The plan includes three mining panels (0, 1, and 2), with the HNE deposit located in the northern portion of Panel 1.

Underground development on the JV Property’s Panel 1 began in October 2024. As of April 30, 2025, OTLLC had completed approximately 152 meters of lateral development. First underground production from the JV Property is anticipated in 2027.