Hafnium (Hf) has no independent ore in nature; it is always closely symbiotic with zirconium (Zr) in a homogeneous form, and accounts for only approximately 2% of Zr. Zr and Hf have similar physical ...

The Dubbo project is a large inground polymetallic resource of zirconium, hafnium, niobium, tantalum, yttrium and rare-earth elements. It has an 18.9-million-tonne mineral ore reserve and a ...