1. view the smoothness
Face-to-face overlapping two pieces of the same kind of bricks together, align the corners, turn one, turn easy quality is poor, otherwise good. This method cannot be used to detect the antique brick. Antique brick is characterized by arbitrary changes of surface colors and patterns, surfaces can be uneven.
2. using a diagonal sizes, this method is relatively simple
Face-to-face overlapping two pieces of the same kind of bricks together, align the corners, turning a, clip size is always good. This method is particularly suitable for smooth surface of the ceramic tile testing.
This is an important indicator of detecting quality of polished tile. Polished surface protection wax using a soft clean cloth or reagents, placed in the light, or the Sun, at a 45-degree angle of view, the brighter the better.