West Perth diamond developer and producer Dwyka Diamonds Ltd has signed an earn-in agreement with BHP Billiton worth $6.6 million, which will see the giant earn a 50 per cent interest in subsidiary Danyland Ltd.

West Perth diamond developer and producer Dwyka Diamonds Ltd has signed an earn-in agreement with BHP Billiton worth $6.6 million, which will see the giant earn a 50 per cent interest in subsidiary Danyland Ltd.