Sentinel Metals Limited has secured an exclusive option to acquire a 1% production royalty held by Amazon Mining Company over 13 patented claims at its Columbia Gold-Silver Project in Montana, USA.

The agreement, executed by Sentinel subsidiary Great Plains Mining, LLC, provides a pathway to reduce the project's effective aggregate royalty from approximately 3.8% to 3.2%, representing a reduction of roughly 16% on a resource-weighted basis. The patented claims host about 500,000 ounces of the project's current 920,000-ounce mineral resource.

The purchase price is fixed at 500 ounces of gold, which can be maintained for up to seven years through annual payments of 5 ounces of gold. All annual option payments are fully credited against the 500-ounce purchase price, and the company can terminate the agreement at any time without penalty. The term can be extended by up to three additional one-year periods if permitting delays development.

The remaining consideration consists of a single balloon payment due only if and when Sentinel elects to exercise the option, which is expected at or around a final investment decision. Sentinel listed on the ASX in October 2025, raising $10 million to fund development activities at the asset.

“This is a 36-year-old royalty that pre-dates the current Columbia Mineral Resource Estimate, and we have now locked in the right to remove it for 500 ounces of gold, irrespective of how large the Columbia Resource ultimately becomes.”

— Matt Herbert, Managing Director & CEO

The company is targeting the release of an updated mineral resource estimate for the project in November 2026 as it advances ongoing technical and de-risking work.

“With Big Springs in Nevada now in the portfolio and the updated Columbia Resource targeted for November 2026, we are systematically working through the key items that can de-risk the future development of the project.”

— Matt Herbert, Managing Director & CEO

This systematic de-risking approach coincides with ongoing technical studies and environmental baseline monitoring across the Montana property as the team prepares for the upcoming resource update.

Read the full announcement: Sentinel secures right to buy out legacy royalty at Columbia