Rare earth elements from heavy mineral sands: assessing the potential of a forgotten resource

Heavy mineral (HM) sands are usually exploited for titanium and zirconium minerals such as rutile, ilmenite and zircon, but also contain a variety of possible co/by-products, including critical metals such as rare earth elements (REE) in minerals such as monazite and xenotime. The global HM sands industry remains dominated by Australia, which until the mid-1990s included the export of monazite concentrates for REE extraction and provided ∼15–30% of world REE production. The lack of recognition for HM sands as a potential REE resource adds to confusion about potential REE supplies. This study presents a comprehensive assessment of Australian HM sand resources, including an assessment of likely contained monazite, showing that these REE can potentially double the value of a HM sand project. As such, there remains significant opportunities for HM sands projects to increase their economic value by also extracting monazite and xenotime for their REE, with further research needed to assess environmental and radioactivity issues.