Physical Properties of Actinium and Roentgenium
Melting Point
1,227.00 °C
  
38
Not Available
  
Boiling Point
3,200.00 °C
  
26
Not Available
  
Appearance
  
  
Physical State
Solid
  
Solid
  
Color
Silvery White
  
Silver
  
Luster
NA
  
Unknown Luster
  
Hardness
  
  
Speed of Sound
Not Available
  
Not Available
  
Optical Properties
  
  
Allotropes
No
  
No
  
α Allotropes
Not Available
  
Not Available
  
β Allotropes
Not Available
  
Not Available
  
γ Allotropes
Not Available
  
Not Available