Thulium was discovered by Per Theodore Cleve at 1879 in Sweden.
Origin of name: named after ""Thule", an ancient name for Scandinavia.
Atomic Number: 69
Atomic Weight: 168.93421
Melting Point: 1818 K (1545°C or 2813°F)
Boiling Point: 2223 K (1950°C or 3542°F)
Density: 9.32 grams per cubic centimeter
Phase at Room Temperature: Solid
Element Classification: Metal
Period Number: 6 Group Number: none Group Name: Lanthanide