Three equal axes at right angles.
Two equal axes at 120°, third at a right angle.
Three unequal axes, one at a right angle.
Three unequal axes at right angles.
Two equal axes, all at right angles.
Three unequal axes, none at right angles.
Subtype of hexagonal with a three-fold axis of rotation.
Broadest classification of crystals based on the symmetry of their unit cells.