The present invention relates to a method for producing cubic boron
nitride abrasive grains used for producing a grinding wheel, etc., and to
cubic boron nitride abrasive grains. The method comprises maintaining a
mixture containing hexagonal boron nitride and seed crystals of cubic
boron nitride under pressure and temperature conditions where cubic boron
nitride remains thermodynamically stable, characterized in that the seed
crystals contain cubic boron nitride twin crystals.