To judge and select a good polished tile, we must do the following five words: 1. Look. Look at the color uniformity and surface finish of the tile. Extract four or five pieces of tiles from a box , check if there are no defects such as color difference, bending, missing corners, and scarath on the surface etc. 2.Knock. Tap bricks with hard objects. The crisper the sound, the higher the degree of vitrification and the better the quality. You can also clamp the corner of the tile with your left thumb, forefinger, and middle finger, and hang it easily. Tap the lower part of the tile with your right index finger. If the sound is clear and pleasant, it is very OK. If the sound is boring and stagnant, of course it is not OK. 3.Drop. Put colored water droplets (such as ink) on the front of the tile and let it stand for one minute. Wipe it with a damp cloth. If there is a mark on the brick surface, it means that dirt has been sucked into the brick. If the brick surface is still bright as a mirror, the tile is