Physical Properties of Beryllium and Promethium
Melting Point
1,278.00 °C
  
36
1,042.00 °C
  
99+
Boiling Point
2,970.00 °C
  
32
3,000.00 °C
  
31
Appearance
  
  
Physical State
Solid
  
Solid
  
Color
White Gray
  
Unknown
  
Luster
Metallic
  
Metallic
  
Hardness
  
  
Mohs Hardness
Not Available
  
Brinell Hardness
Not Available
  
Vickers Hardness
1,670.00 MPa
  
4
Not Available
  
Speed of Sound
12,890.00 m/s
  
2
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