Is it possible to tell if natural stone tiles are sealed properly?
If you pour an egg cup of water on to your natural stone floor it should pool on the surface in a large droplet. Leave the water for ten minutes, when you return, it should remain on the surface of the stone. If the water has absorbed into the floor and left a dark patch then the floor requires additional sealant. To test stone wall tiles, splash water onto your tiles and the liquid should run down the tiles like rain drops running down a window pane.