Protactinium

Protactinium
Properties
Atomic symbol	Pa
Atomic number	91
Classification	Metallic
Atomic mass	231.03588 amu
Other Information
Date of discovery	1913
Name of discoverer	Kasimir Fajans and O.H. Göhring
Name origin	From the Greek Protos meaning first.
Uses	None
Obtained from	Occurs in minute trace amounts in uranium ores, but chiefly amongst the fission products of uranium, thorium, and plutonium. In 1961 the UK Atomic Energy Authority produced 125g of pure protactinium from uranium fuel elements, which represents the major world stock of protactinium.