REFLECTIVITY

Natural stone contains crystals that reflect light and produce a shiny surface. If these crystals brake or are crushed, they no longer reflect light evenly. An example: when glass from a flashlight breaks, it can't reflect the light of its bulb anymore.

Polished stone flooring looses its gloss when heavy traffic together with sediments breaks its crystals. This might happen if the pressure of shoes drive sediments into the stone or break its crystals.