In this way a mixture of the two asparagines was obtained, which were separated by picking out the hemihedral crystals.
The occurrence of hemihedral faces was considered by Pasteur to be a sufficient criterion for an optically active substance.
These systems, however, only represented holohedral forms, leaving the hemihedral and tetartohedral classes to be explained.
In this species the hemihedral variety, Hemiaspis, often occurs.
It may be considered as the hemihedral form of the ditetragonal bipyramid.