Tantalum is a metallic element with an atomic number of 73 and a chemical symbol of Ta. The corresponding elemental substance of the element is a steel gray metal, which has extremely high corrosion resistance. It does not react with hydrochloric acid, concentrated nitric acid, or "aqua regia" under cold and hot conditions.

Tantalum mainly exists in tantalite, coexisting with niobium. Tantalum has a moderate hardness and ductility, and can be drawn into thin wire foil. Its coefficient of thermal expansion is very small. Tantalum has excellent chemical properties and high corrosion resistance. It can be used to manufacture evaporating utensils, etc., as well as electrodes, rectifiers, and electrolytic capacitors for electronic tubes. Used medicinally to make thin sheets or threads to repair damaged tissue. Although tantalum has a strong corrosion resistance, its corrosion resistance is due to the formation of a stable tantalum pentoxide (Ta ₂ O ⏴) protective film on the surface.