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Mineral sand deposits in the Murray Basin offer the potential for significantly expanding Australia's production of ilmenite, rutile and zircon. Since prices of zircon and rutile are higher than ilmenite, and zircon grades in most deposits are significantly higher than those for rutile, zircon often is the major economic mineral component in mineral sand deposits. Two types of deposits occur in the Murray Basin. They comprise strandline deposits, in which the particle size of the heavy minerals is similar to that in other Australian deposits, and fine grained, sheet-like, WIM style, deposits. While production from several strandline deposits has commenced, the fine grained deposits, which contain significantly greater amounts of mineralisation, are still to be developed. Problems with processing the finer particle size of the mineralisation, its variable mineralogy, higher surface and lattice impurity levels, in particular uranium and thorium in zircon grains, have contributed to this. Overcoming these problems is necessary to obtain the full commercial value from the Murray Basin deposits. Processing to recover a fine grained zircon concentrate from the extensive WIM style deposits and the removal of impurities in the concentrate are discussed in this paper. In particular, treatments to remove surface and lattice impurities, and to lower uranium and thorium levels by an acid leach and with heat and leach treatments, are reviewed. The conditions used in the heating treatment (e.g. temperature and nature of any fluxes added) affect the impurity removal and whether zirconia (ZrO2) or zircon (ZrSiO4) is obtained as the product.