Small hecatonicosihexacosihecatonicosachoron

The small hecatonicosihexacosihecatonicosachoron, or shixhi, is a nonconvex uniform polychoron that consists of 600 truncated tetrahedra, 120 small dodecicosahedra, and 120 truncated dodecahedra. Two truncated tetrahedra, two small dodecicosahedra, and two truncated dodecahedra join at each vertex.

Vertex coordinates
The vertices are the same as those of the regiment colonel, the sphenoverted hecatonicosidishexacosichoron.