Diagonal ratio dimension
Two pieces of the same kind of brick face to face overlap, four corners aligned, rotating one of the four sides of the same size is always good. This method is especially suitable for glazed tile inspection.
Check the flatness
Two pieces of the same kind of brick face to face overlap, four corners alignment, rotating one of the pieces, easy to turn, poor quality, and vice versa. This method can not be used to detect antique brick. The remarkable feature of archaize brick is the arbitrary change of surface color and pattern, and the surface can be uneven.
Look at the water absorption rate
The size of water absorption is an important sign of tile quality. When a small cup of water is poured on the back of the brick, the faster the water disappears, the higher the water absorption rate is, the looser the texture is and the weaker the strength is.
Look at the smoothness
This is an important indicator of the quality of polished tiles. Clean the surface of the polished tile with soft cloth or reagent. Put it in the light or sunlight, and see the angle of 45 degrees. The brighter the surface, the better.