Castle Minerals Ltd. said Aug. 14 that Iguana Resources may acquire up to an 80% interest in the Degbiwu and Gbiniyiri gold-zinc licenses in the Wa project in Ghana's Upper Western region by spending US$11.7 million in three stages over five years through a binding farm-out agreement with Castle Minerals subsidiary Carlie Mining, which owns the licenses.

Iguana must spend US$4.7 million on exploration for over three years with a minimum spend of US$1.2 million on the Degbiwu license and US$500,000 on the Gbiniyiri license in the first year to earn an initial 51%. It can acquire an additional 14% by solely funding US$1.5 million in exploration in the second year and an additional 15% by solely funding US$5.5 million in exploration in the third year.

Iguana will be the operator of the project, and should it decide not to sole fund it for the next exploration, both parties will enter into a joint venture agreement to co-fund it. Iguana must pay a minimum of US$250,000 before it can withdraw from the agreement.

In June 2018, Castle Minerals said it was considering selling Carlie Mining.