Gina Rinehart’s Hancock Prospecting, armed with an $18 billion investment war chest, has turned its attention to rare earths and appears to have set the scene for an intriguing battle for strategic assets with Andrew Forrest’s Fortescue Metals Group.

The two Perth-based iron ore billionaires – Mrs Rinehart holds top spot on The Australian Financial Review Rich List and Dr Forrest is in second place – have both signalled their intentions to become major players in rare earths.