Physical Properties of Iron and Niobium
Melting Point
1,535.00 °C
  
25
Boiling Point
2,750.00 °C
  
37
2,468.00 °C
  
99+
Appearance
  
  
Physical State
Solid
  
Solid
  
Color
Gray
  
Gray
  
Luster
Metallic
  
Metallic
  
Hardness
  
  
Speed of Sound
5,120.00 m/s
  
8
3,480.00 m/s
  
21
Optical Properties
  
  
Reflectivity
Not Available
  
Allotropes
Yes
  
No
  
α Allotropes
Ferrite (alpha Iron)
  
Not Available
  
β Allotropes
beta Iron
  
Not Available
  
γ Allotropes
gamma Iron
  
Not Available