Tunnelled truncated octahedron

The tunnelled truncated octahedron is a quasi-convex Stewart toroid. It can be formed by excavating a triangular cupola and a truncated tetrahedron from a truncated octahedron to form a tunnel.

Unlike the similar tunnelled truncated cube there is only one way to position the tunnel without faces intersecting.

The tunnelled truncated octahedron has the notable property that its faces can be colored with seven colors such that every color is contiguous and every color is adjacent to every other color.