Barium hexaboride is a hard material with a high melting point. It can be formed by passing a barium vapour at >750 °C over boron crystals:
Ba + 6B → BaB₆
However, it can also be formed by reacting barium chloride with boron in two stages: firstly... Wikipedia
Chemical formula: BaB6
Molar mass: 202.21 g/mol
ChemSpider ID: 4891895