WIM150 mineral sand deposit, Murray Basin, Australia: geology and mineral resources

Abstract

The first significant heavy mineral sands discovery within the Murray Basin, Australia, was made in 1982 at the WIM150 deposit near Horsham, Victoria. This fine-grained (20–75 µm) deposit formed in an offshore environment (WIM-style deposit). The heavy minerals (HM) are within the Loxton Sand, which is prospective throughout the Murray Basin for HM in both strandlines and WIM-style deposits. At WIM150, HM are concentrated in a horizon that extends for 10 km north–south and 12 km east–west and has a thickness that ranges from 2 to 22 m with an average of 11.2 m. Measured, Indicated and Inferred Mineral Resources totalling 1650 million tonnes at 3.7% total HM were estimated in 2013. Test work has demonstrated that the resource can be processed to +20 µm and that the 20–38 µm size fraction contains significant concentrations of HM (14.8% of the HM within the 20–75 µm size fraction). Test work also demonstrated that the HM from the 20 to 38 µm size fraction contain more than 40% ZrO₂ and CeO₂ (assumed to be contained in zircon and monazite, respectively). The project is estimated to have an Ore Reserve mine life of 55 years and is the most advanced, in terms of development, of the Murray Basin WIM-style deposits. A definitive feasibility study for the WIM150 deposit was completed in mid-2013.

Keywords:

• Murray Basin
• Heavy mineral sands
• Zircon

Acknowledgements

The authors wish to thank Australian Zircon NL for their permission to publish this paper. Work by external consultants undertaken on behalf of Australian Zircon NL is gratefully acknowledged.