Thulium
Symbol: Tm

Atomic Number: 69
Atomic Weight: 168.934
Protons: 69
Neutrons: 100
Electrons: 69
Lanthanide Series

Brief Description:
Thulium is the least abundant of the earth elements, being about as rare as silver, gold, or cadmium. It is malleable and ductile, and soft enough to be cut with a knife. Like many of the rare-earth elements, is silver/gray in appearence. Thulium can be found in minerals such as monazite.