9-2 step prism

The 9-2 step prism is a convex isogonal polychoron, member of the step prism family. It has 27 phyllic disphenoids of three kinds as cells, 12 joining at each vertex. Together with its dual, it is the second in an infinite family of triangular dihedral swirlchora.

Isogonal derivatives
Substitution by vertices of these following elements will produce these convex isogonal polychora:
 * Phyllic disphenoid (9): 9-2 step prism
 * Scalene triangle (9): 9-2 step prism
 * Scalene triangle (19): 19-2 step prism
 * Edge (9): 9-2 step prism