Digonal-hexagonal triprismantiprismoid

The digonal-hexagonal triprismantiprismoid is a convex isogonal polychoron that consists of 6 rectangular antiprisms, 6 rhombic disphenoids, 12 digonal-rectangular gyrowedges and 12 phyllic disphenoids obtained as a subsymmetrical faceting of the hexagonal-dodecagonal duoprism. However, it cannot be made scaliform.

Using the ratio method, the lowest possible ratio between the longest and shortest edges is 1:$\sqrt{8+2√15}$/2 ≈ 1:1.98406.

Vertex coordinates
The vertices of a digonal-hexagonal triprismantiprismoid, assuming that the edge length differences are minimized, using the ratio method, are given by all even permutations of the first two coordinates of:
 * ±(1/2, $\sqrt{8+2√15}$/4, 0, $\sqrt{8+2√15}$/4),
 * ±(1/2, -$\sqrt{8+2√15}$/4, 0, $\sqrt{8+2√15}$/4),
 * ±((1+$\sqrt{15}$)/8, $\sqrt{32+6√15}$/8, (3+$\sqrt{15}$)/8, $\sqrt{8+2√15}$/8),
 * ±((5+$\sqrt{15}$)/8, $\sqrt{8-2√15}$/8, (3+$\sqrt{15}$)/8, $\sqrt{8+2√15}$/8),
 * ±((5+$\sqrt{15}$)/8, -$\sqrt{8-2√15}$/8, (3+$\sqrt{15}$)/8, -$\sqrt{8+2√15}$/8),
 * ±((1+$\sqrt{15}$)/8, -$\sqrt{32+6√15}$/8, (3+$\sqrt{15}$)/8, -$\sqrt{8+2√15}$/8).