A method of making pre-grouted mosaic panels, wherein each panel (1) is formed from a plurality of mosaic tiles (2) each having a upper surface (4) and a lower surface (5), the tiles (2) being laid over a substantially horizontal support base (S) in mutually spaced positions, to define a plurality of grooves (3). The method includes a step of placing a first thermoformable polymeric sheet element (10) on the upper (4) and lower (5) surfaces of the mosaic tiles (2) and a later step of thermoforming the first sheet element (10) for the latter to at least partially fill the grooves (3) when it is thermoformed. A pre-grouted mosaic panel that can be obtained by such method.

A paving slab. The paving slab has a unitary body made of concrete-based material, the body having sidewalls extending between top and bottom faces, providing the body with a thickness. The top face is provided with longitudinal false joints defining rows extending from a first to a second side of the unitary body. The first side has a staggered outline and the second side has a stepped outline, the first and second sides being able to engage with respective first and second sides of an adjacent slab shaped as the paving slab, but rotated by 180 degrees. When several of the slabs are assembled on a surface, it creates an illusion that the surface is covered by individual plank pavers randomly assembled.

A kit that includes multiple rectilinear elongate polygonal elements having five unique shapes, four of which are concave polygonal elements. In some examples, when arranged with respect to one another, the elements of the kit form a girih strapwork pattern. In one aspect, respective elements in a kit may include bezels or boarders along longer sides to enhance an over/under weaving effect of the girih strapwork pattern. In other aspects, one or more elements may be formed as a tray, and some of the trays may include various components or materials disposed in the tray (e.g., architectural surface materials, biological systems, various electronic components) to provide for a variety of creative designs and structural/sculptural installations for built environments. In some implementations, one or more such trays may have beveled rims so as to appear light and thin when viewed.