According to the size of the allowable deviations, flatness and angle allowable tolerances, as well as the appearance of quality, surface finish and other indicators. Marble slabs are divided into three grades: excellent products, first-class products and qualified products; the grade and identification of marble plates are mainly identified through the detection of instruments and measuring tools.
Check appearance quality
Different grades of marble have different appearances. Because marble is naturally formed, defects are inevitable. At the same time, the pros and cons of processing equipment and measuring tools are also the causes of sheet defects. Some plates are not full (warped or sag), plates have defects (cracks, blisters, stains, etc.), plate body specifications (such as lack of edges and corners, the body is not correct) and so on. According to national standards, all grades of marble slabs are allowed to have certain defects, but superior products are not so obvious.
The marble plates are colorful, varied in color, and have different patterns. This is exactly the charm of marble plates. The color tone is basically the same, the color difference is small, and the beautiful pattern is a concrete expression of the fine variety, otherwise it will seriously affect the decorative effect.
Detect surface gloss
The level of gloss on the marble plate surface will greatly affect the decorative effect. In general, the polished surface of a high-quality marble plate should have a mirror-like gloss and clearly reflect the scenery. However, due to the different chemical compositions of marbles of different qualities, the difference in glossiness will be great even for products of the same grade. Of course, the surface gloss of the board between different grades of the same material will also have some differences. In addition, the strength and water absorption of marble plates are also important indicators for evaluating marble quality.