Rio Tinto Exploration has signed an agreement to invest up to $60m on exploration in Antipa Minerals' Citadel gold and copper project in Western Australia.
Antipa Minerals managing director Roger Mason said: "Antipa is delighted to join with Rio Tinto, in the future exploration of the Citadel project in the world class Paterson Province of Western Australia.
"We believe that Rio Tinto's involvement will add significantly to the prospects of developing a successful mining operation within the Citadel project area."
Initially, Rio Tinto plans to invest $3m to complete follow-up phase II RC drilling programme at Calibre during the calendar year.
The programme will involve the completion of up to 30 RC drillholes and 5,000m would be divided into three stages.
According to Antipa Minerals, the three stage programme is aimed at extending the limits of the North Calibre gold-copper mineralisation to a total strike length of between 1.6km and 3.9km.
Under the farm-in agreement, Rio Tinto may acquire up to a 75% joint venture (JV) interest in the Citadel project.
Within 18 months of the agreement starting, the company will fund $3m in exploration expenditure on the Citadel project tenements.
In order to proceed to stage II, Rio Tinto will fund a further $8m in exploration expenditure on the tenements within three years to earn a 51% interest in it.
The company will have to fund a further $14m in exploration expenditure on the tenements within three years to earn a 65% joint venture interest if it plans to proceed to stage III.
By funding a further $35m during stage four, Rio Tinto can earn a 75% joint venture interest.
Upon Rio Tinto earning a 51% interest in the Citadel project, the companies will become parties to a JV agreement in terms that were already agreed.
Image: Airborne magnetic image showing magnetic trend associated with the Calibre North high-grade gold and copper mineralisation. Photo: courtesy of Antipa Minerals Limited.