Centrex Metals Ltd. sold its Wilgerup and Kimba Gap iron ore projects in South Australia to OneSteel Manufacturing Pty. Ltd.-owned SIMEC Mining.

The company will receive royalty streams, capped at A$5 million each, when mining starts at each project, it said March 22.

Centrex can claim back any of the two projects on which OneSteel has not started development within 10 years.

The company intends to focus on its fertilizer mining developments, including its flagship Ardmore phosphate rock project in North West Queensland, Australia.

Centrex's recent scoping study for Ardmore estimated a pretax net present value, discounted at 10%, of approximately A$124 million to A$129 million, an internal rate of return of 39% to 42% and a three-year payback.