This puzzle shows a dissection of a truncated tetrahedron into 4 octahedra and 6 tetrahedra. The octahedra around the titanium atoms share edges and vertices to form a 3-D network. Potassium alum crystallizes in regular octahedra with flattened corners and is very soluble in water. Diamonds occur most often as euhedral or rounded octahedra and twinned octahedra known as "macles". There are 257 topologically distinct "convex" octahedra, excluding mirror images. It has 4 truncated octahedra around each vertex. Rutile also shows a screw axis when its octahedra are viewed sequentially. It adopts the anti-ReO structure with a simple lattice made up of NNa octahedra. The basic structure forms stacked sheets of linked octahedra. Another is a tessellation of octahedra and cuboctahedra. The structure of TcCl is composed of infinite zigzag chains of edge-sharing TcCl octahedra. The cluster can be visualised as being composed of three face-sharing octahedra. Metal tetrahalides often exist as polymers with edge-sharing octahedra. The three-dimensional framework is formed by the octahedra sharing O corners. Mg(HO) octahedra occupy the open spaces within the KCl octahedra.