Hafnium 5. October 2015elementadmin ◄ Lu Ce ▲ ▼ Pb Ta ► 72 Hf hafnium 178.49 72 Hf 4 Hf litho Hafnium ∙ hafnium ∙ hafnio ∙ hafnio group IV: RH4, RO2 melting point: 2227°C boiling point: 4602°C density: 13.2 g/cm³