Boron is a chemical element with symbol B and atomic number 5. Produced entirely by cosmic ray spallation and supernovae and not by stellar nucleosynthesis, it is a low-abundance element in the Solar system and in the Earth crust.

Atomic Weight:  10.81
Density:        2.46 g/cm3
Melting Point:  2075 °C
Boiling Point:  4000 °C