Multi-sided paving stone - has four corners at corners of polygon and elementary sides of facets not parallel to polygon sides

摘要

The facets of the paving-stone join at the four corners to form an angle corresponding to that of the polygon, square, oblong, hexagon or octagon, within which the paving stone is described. The elementary side of the paving-stone has a centre of symmetry, and is formed of at least five facets, none of which is parallel to the corresponding side of the polygon circumscribed. The facets of half the elementary side, joining one vertex to the centre of symmetry, are situated on each side of the straight line connecting the vertex of the side to its centre of symmetry.