Physical Properties of Neptunium and Uranium
Melting Point
1,132.00 °C
  
39
Boiling Point
3,902.00 °C
  
13
3,818.00 °C
  
16
Appearance
  
  
Physical State
Solid
  
Solid
  
Color
Silver
  
Silvery Gray
  
Luster
Metallic
  
Metallic
  
Hardness
  
  
Mohs Hardness
Not Available
  
Brinell Hardness
Not Available
  
2,350.00 MPa
  
2
Vickers Hardness
Not Available
  
1,960.00 MPa
  
2
Speed of Sound
Not Available
  
3,155.00 m/s
  
25
Optical Properties
  
  
Allotropes
No
  
No
  
α Allotropes
Not Available
  
Not Available
  
β Allotropes
Not Available
  
Not Available
  
γ Allotropes
Not Available
  
Not Available