Great inverted retrosnub icosidodecahedron

The great inverted retrosnub icosidodecahedron or girsid, also called the great retrosnub icosidodecahedron, is a uniform polyhedron. It consists of 60 snub triangles, 20 additional triangles, and 12 pentagrams. Four triangles and one pentagram meet at each vertex.

Measures
The circumradius of the great inverted retrosnub icosidodecahedron with unit edge length is a real root of: $$4096x^{12}-27648x^{10}+47104x^8-35776x^6+13872x^4-2696x^2+209$$