Hafnium is a rare transition metal that has a silvery color and luster. Powdered dark grey. Refers to strong and refractory, becomes liquid at 2233 °C. Thanks to the oxide film, it is quite inert, resistant to acids on a par with glass, and has a water-repellent property. In its pure form, this metal is characterized by good ductility and high ductility to machining.
Zirconium is a gray transition metal with a silvery sheen. Plastic. It melts at 1855 °C, in powder form it is capable of self-ignition at ordinary temperatures. Refers to paramagnets. It is resistant to corrosion, radiation, is immune to alkali solutions, sulfuric (up to 50%) and hydrochloric acids.