Basic Information

Name: Promethium 
Symbol: Pm 
Atomic Number: 61 
Atomic Mass: (145.0) amu 
Melting Point: Unknown 
Boiling Point: Unknown 
Number of Protons/Electrons: 61 
Number of Neutrons: 84 
Classification: Rare Earth 
Crystal Structure: Hexagonal 
Density @ 293 K: 6.475 g/cm3 
Color: Unknown
Date of Discovery: 1945 
Discoverer: J.A. Marinsky 
Name Origin: From the god Prometheus (who stole fire of the sky and gave it to man) 
Uses: No uses known 
Obtained From: fission products of uranium, thorium, plutonium