一观察法在光照良好的环境里看磁砖的釉面是否有色差裂纹气泡针孔黑点划痕缺角等瑕疵镜面效果是否强烈二听音法用手轻敲磁砖本体若声音清脆悦耳有金属音质者则砖的密度高烧结好为品质优良反之如声音沙哑可能砖体内有裂纹瓷化程度低? A  observation method in a bright environment  see tile glaze whether there is color  crack  bubble  pinhole  black spots  scratches  missing corners and other defects  whether the mirror effect is strong    listening method Hand tapping the body of the tile  if the sound is crisp  sweet ears  metal sound quality  the density of the brick  sintered good  for good quality  the contrary  the sound such as hoarse  may have cracks in the brick  low degree of porcelain?