1. Different grades of marble plates have different appearances. Because marble is made naturally, disadvantages are inevitable. The quality of processing equipment and measuring tools is also the cause of sheet defects. Some plates are not full (warped or sunken) and have defects (cracks, sand holes, spots, etc.). ), and the standards are different (such as lack of edges and corners, wrong plates). According to the national standards, all grades of marble plates are allowed to have certain shortcomings, but the superior products are not so obvious. Choose variegated colors. Marble plates are colorful, colorful and striped, which is the precious charm of marble plates. The colors are basically the same, the color difference is small, and the stripes are beautiful, otherwise the decorative effect will be seriously affected. Detecting the unevenness of the external gloss of marble plates will greatly affect the decorative effect. Generally speaking, the polished surface of marble plate should have a mirror-like luster, which can clearly reflect the scene. However, due to the different chemical composition of different quality marble, even the products of the same grade will have great differences in gloss. Of course, there will be some differences in the surface gloss of different grades of the same raw material. In addition, the strength and water absorption of marble slab are also important indexes to evaluate the quality of marble.
2. Diagonal scale: Two bricks of the same kind are stacked face to face, with four corners aligned and one of them rolling. The diatonic scale is always the same. This method is especially suitable for the detection of externally lubricated tiles. Check the flatness. Stack two bricks of the same kind face to face, align the four corners and roll one of them. Simple rolling quality is poor, and vice versa. This method cannot be used to detect antique bricks. The remarkable feature of antique brick is that the appearance color and markings can be changed at will, and the appearance can be uneven.