A rare-earth metal with the symbol Tm and atomic number 69. It is the thirteenth and third-last element in the lanthanide series. Thulium is a silvery-gray metal that is fairly soft and slowly tarnishes in air. It is used in portable X-ray machines, solid-state lasers, and high-temperature superconductors.

Thulium belongs to the Lanthanide family. Thulium is a silvery metal, so soft it can be cut with a knife. Thulium is stable in air, but reacts slowly with water, and rapidly with acids.

Thulium is an lanthanide element with atomic number 69.

The symbol for tantalum is Ta.

No.