Atomic number: 103
Symbol: Lr (originally Lw)
Category: actinide
Density at 25°C: solid: n/a
This is the last of the actinides. This element has a half life of 3.5 hours. Test have shown that it is chemical similar to lutetium , which sits just above it on the periodic table. Only a few atoms were produced initially in laboratories in Dubna and Berkeley.