Small retrosnub icosicosahedron

The small retrosnub icosicosahedron, sirsei, or compound of five great icosahedra is a uniform polyhedron compound. It consists of 100 triangles (20 pairs of which form hexagrams due to following in the same plane), with five faces joining at a vertex.

It can be formed from the pentagrammatic snub pseudicosicosahedron by replacing each small stellated dodecahedron with the great icosahedron with which it shares its edges.

Its quotient prismatic equivalent is the pyritohedral great icosahedral pentachoroorthowedge, which is seven-dimensional.

Vertex coordinates
Its vertices are the same as those of its regiment colonel, the pentagrammatic snub pseudicosicosahedron.