Grade 1 tiles:

According to the first-class ceramic tile grading standard, as the name implies, tiles are marketed perfectly and without any defects in the surface of the glaze. These tiles are the only sample of tiles that are flawless and the rest of the tiles each have their own disadvantages depending on their grade.

Grade 2 tiles:

Grade 2 tiles may have several defects in appearance. Of course, this defect is negligible due to the lower grades. First, in this degree of tile there is one or two points at a maximum diameter of half a millimeter or unglazed point, at a maximum diameter of 2 x 3 mm at a distance of 2-3 centimeters on the surface. The likelihood of curvature in these tiles is lower than the third and fourth degrees.