Tantalum is a chemical element with the symbol Ta and atomic number 73. Previously known as tantalium, it is named after Tantalus, a villain from Greek mythology. Tantalum is a rare, hard, bluegray, lustrous transition metal that is highly corrosionresistant. It is part of the refractory metals group, which are widely used as minor components in alloys.
columbite shows a fast solubility rate less than 100 hrs and dissolution half time of (t1/2) of 34 h while in pyrochlore t1/2 is 54 hrs and in columbitetantalite t1/2 is 64 hrs. The densities of columbite, pyrochlore and columbitetantalite being, and g/cm3. The high