Physical Properties of Thorium and Thallium
Melting Point
1,750.00 °C
  
17
Boiling Point
1,457.00 °C
  
99+
Appearance
  
  
Physical State
Solid
  
Solid
  
Color
Silver
  
Silvery White
  
Luster
NA
  
NA
  
Hardness
  
  
Vickers Hardness
Not Available
  
Speed of Sound
2,490.00 m/s
  
36
818.00 m/s
  
99+
Optical Properties
  
  
Allotropes
No
  
No
  
α Allotropes
Not Available
  
Not Available
  
β Allotropes
Not Available
  
Not Available
  
γ Allotropes
Not Available
  
Not Available