Antilles Gold (ASX:AAU) said the notice to proceed was issued on Dec. 31, 2025, to Yantai Xinhai Mining Technology & Equipment under the $29.5 million engineering, procurement, and construction contract for the Nueva Sabana mine in Cuba, according to a Monday filing with the Australian bourse.

The contract covers roughly 85% of the remaining $35 million of development costs, the filing said.

The balance of $6.5 million for earthworks, high-tension power connection, water supply, construction management and contract administration is managed by 50%-owned Minera La Victoria, per the filing.

Antilles Gold shares fell 10% in afternoon trade Monday.