Grinding of marble
First of all, grinding means that the floor is « scratched » and « smoothed » by means of an abrasive element. A rotating machine equipped with diamond grains will scrape the stone to bring the intact layer to the surface. Grinding also allows to remove the edges between the tiles (edge grinding) but also to remove the stains and cracks on the surface.
Mechanical polishing of marble
Mechanical polishing is a similar process but the used diamond grains are much finer than when grinding. Each step of polishing makes it possible to remove the scratches made during the preceding step, to obtain ultra fine scratches which are no longer visible to the naked eye. As the polishing continues, the roughness of the stone disappears and a mechanical gloss appears. The illustrations below show how the light is optimally reflected when the stone is perfectly smooth.