Description: The method suggested by Rogers. On the left the hexoctahedron can be squashed in some different ways to get the special forms for G=m3m. Press it on the red points and you will get the trisoctahedron; press the green points and get the trapezohedron; the yellow dots for the tetrahexahedron; press the brown star and get the dodecahedron; the pink star for the octahedron; and the green star for the cube. But now try it again with the tertartoid on the right (G=23). You will only get a cube (green square) and a octahedron (red triangle). What about the rest of the special forms?

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