Frequently used materials are dried sand, very fine stones, marble powder, etc. Particle size is up to the costumer’s requirements but most common used is 0.1 – 0.6 mm. In addition to their aesthetic properties, these give the A1 a scratch-resistant and extra-hard top layer. By using sand of different colour and size, a granito or granite appearance can be obtained. In this case, after curing, the top layer can be sanded to bring the stone to the surface to obtain a greater contrast. Sand from the seaside is not suitable as it contains salts.
A special filler is expanded glass (Poraver), these are lightweight recycled glass balls. The main advantage is weight saving. For a good adhesion between the grains, it is possible to mix them beforehand with a limited quantity of A1. Poraver is only suited for indoor projects.