The boride was obtained as a by-product during the synthesis of cubic BN at 40 to 70kbar and 1500 to 2200C. The diboride was in the form of golden yellow platelets. The lattice parameters were a = 3.083 and c = 3.523Å. This suggested that material prepared at high pressures had the same structure as that of material prepared by conventional means. The diamond pyramid hardness as 1260kg/mm2.

Magnesium Borides Prepared under Ultra-High Pressure. N.E.Filonenko, V.I.Ivanov, L.I.Feldgun, M.I.Sokhor, L.F.Vereshchagin: Doklady Akademii Nauk SSSR, 1967, 175[6], 1266-9