Murray Basin — Victoria, South Australia, New South Wales
Mineral sands depositions in the Murray Basin were formed between 4 and 6 million years ago, when the sea inundated a large part of the low lying Murray and Darling basins, across what are now parts of Victoria, South Australia and New South Wales
A number of major rivers delivered large volumes of heavy minerals to various beach positions during the sea’s gradual retreat from the basin.
This resulted in a number of large mineral sands deposits with substantial percentages of zircon, as well as the higher titanium dioxide minerals of rutile and leucoxene.
Large tabular deposits of low grade and fine grained ilmenite (referred to WIM style deposits) are also found in the Murray Basin.
The beach style deposits are typically long and thin but can contain high heavy mineral grades.
The majority of the deposits are buried by between 10 and 100 metres of sediment.
Ore can be above or below the water table (as in recent Murray Basin deposits).
- Mining is by conventional dry mining techniques.
Iluka has mined multiple deposits in the southern part of the Murray Basin and two strand deposits in the northern part of the basin – Kulwin and Woornak, Rownack Pirro.
The Woornack, Rownack, Pirro deposits displayed an average strip ratio of 9.4.
Iluka’s mining approach in the Murray Basin is to progressively develop a number of these deposits within its resource inventory.
This has required the relocation of mining equipment and the opening up of often short lived, but high grade and rutile dominant assemblage deposits.