Terbium is a chemical element with symbol Tb and atomic number 65. It is a silvery-white, rare earth mGadolinium is a chemical element with symbol Gd and atomic number 64. Gadolinium is a silvery-white, malleable, and ductile rare earth metal.

Atomic Weight: 43.5
Density        75.33
Melting Point: 346.63
Boiling Point: 23.53