1、 Observation refers to observing the surface structure of stones with the naked eye. Generally speaking, stones with a uniform fine material structure have a delicate texture, making them excellent for stone materials; The appearance effect of stones with coarse and unequal grain structures is poor, and their mechanical and mechanical properties are also uneven, with slightly poor quality. In addition, due to the influence of geological processes, natural stone often produces some fine veins and micro cracks in it, which are prone to fracture along these parts, and attention should be paid to removing them. As for the lack of edges and corners, it is particularly important to pay attention when selecting.

二、量，即量石材的尺寸规格，以免影响拼接，或造成拼接后的图案、花纹、线条变形，影响装饰效果。

2、 "Quantity" refers to the measurement of the size and specification of the stone to avoid affecting the stitching or causing deformation of the patterns, patterns, and lines after the stitching, affecting the decorative effect.

三、听，即听石材的敲击声音。一般而言，质量好的，内部致密均匀且无显微裂隙的石材，其敲击声清脆悦耳；相反，若石材内部存在显微裂隙或细脉或因风化导致颗粒间接触变松，则敲击声粗哑。

3、 Listening means listening to the knocking sound of stones. Generally speaking, stones with good quality, dense and uniform interior, and no micro cracks, have a clear and pleasant knocking sound; On the contrary, if there are micro cracks or fine veins in the interior of the stone or if the contact between particles becomes loose due to weathering, the knocking sound is rough and dumb.

四、试，即用简单的试验方法来检验石材质量好坏。通常在石材的背面滴上一小滴墨水，如墨水很快四处分散浸出，即表示石材内部颗粒较松或存在显微裂隙，石材质量不好；反之，若墨水滴在原处不动，则说明石材致密质地很好。

4、 Trial, that is, using a simple test method to test the quality of stone materials. Usually, a small drop of ink is applied to the back of the stone. If the ink is quickly dispersed and leached, it indicates that the internal particles of the stone are loose or there are micro cracks, and the quality of the stone is poor; On the contrary, if the ink droplets remain in place, it indicates that the stone is dense and has a good texture.

有了电梯门套厂家上面的小总结，希望对广大客户有所帮助，如果有什么不理解的或者寻求帮助的请点击我们的网站：http://www.sddtmt.com或者来电咨询，我们会尽全力为您

With the summary above from the elevator door cover manufacturer, I hope it can be helpful to our customers. If you have any questions or need help, please click on our website: http://www.sddtmt.com Or call for consultation, and we will do our best to solve it for you