Deep Yellow (ASX:DYL) unit Reptile Mineral Resources and Exploration struck an earn-in agreement under which Core Energy Minerals (ASX:CR3) can take a majority stake in the Nova Energy (Namibia) joint venture, according to a Wednesday filing with the Australian bourse.

Nova Energy (Namibia) holds two exploration prospecting licenses that together cover about 600 square kilometers west and south-west of the Langer Heinrich uranium mine. The licenses are considered non-core assets of Deep Yellow.

Reptile Mineral Resources currently holds a 65% equity interest in the joint venture, with Nova Energy (Africa) holding 25% and Sixzone Investments the remaining 10%, per the filing.

The agreement allows Core Energy to earn up to a 51% stake in Nova Energy (Namibia) on expenditure of AU$5 million. Under phase one of the deal, Core Energy can acquire a 25% interest on expenditure of AU$2 million within 18 months from the start of the arrangement, and a further 26% in phase two on expenditure of AU$3 million within 24 months from the end of phase one.

After phase two, Core Energy will have a 51% stake in the joint venture, Reptile Mineral Resources about 31.9%, Nova Energy (Africa) roughly 12.3%, and Sixzone with 4.9%.

Deep Yellow shares fell 5% in recent Wednesday trade.