So when choosing and buying ceramic tiles, take note of the following:
Water marks should not be visible in the glaze surface. Tile with water marks only suggests that it absorbs high percentage of water. It usually takes some time before the tile goes back to its original shade.
Tiles must have sufficient bending strength to withstand constant pressure or sudden impact. A durable tile must not be broken even with bare hands.
Tiles must have low water absorption. High water absorption will make the tile fragile. Water Absorption for floor tile should not exceed 10% as prescribed under PNS ISO 13006:2007.
Tiles must not absorb or leave permanent marks from common household stains like coffee, oil, catsup, soy sauce or even methlylene blue or ink.
Glaze on the coating on top should not be chipped when tiles are cut or scratched..