Physical Properties of Promethium and Lanthanum
Physical State
Solid
Solid
Color
Unknown
Silvery White
Mohs Hardness
Not Available
Brinell Hardness
Not Available
Vickers Hardness
Not Available
Speed of Sound
Not Available
α Allotropes
Not Available
Not Available
β Allotropes
Not Available
Not Available
γ Allotropes
Not Available
Not Available