About Stone
slate
“Slate”, the stone for decoration, is also named as “slabstone”. Slate is formed by muddy and clayey sediments (e.g. shale and siltstone) after a mild metamorphism. It will be exfoliated from their original layers or lamellation.
The colours of slate are formed by different components and origins of muddy and clayey rocks under different deposition such as aerated environment. The slate which is used for decoration can be classified into 5 different colours, including black, red-brown, green, yellow and gray, according to their characteristics.
The chemical component of slate is mainly aluminosilicate. Its mineral content comprises clay, fine quartz and mica. Thus, slate is resistance to acid, alkaline and erosion. On the other hand, slate are not very hard in texture, not easily grinded and cannot afford much pressure. Although they have been polished, they are dull. They are suitable for decorating external walls and roofs. Moreover, the procedure for re-processing is simple and the price is not very expensive. slates will be widely used in the future.
For the slates which are harder (after silicification) and have finer texture can be used as making blackboard and snooker table.
Resource for slate is rich in China and the quality is good as well. It is mainly for exporting to Europe, America and Southeast Asia such as Korea and Japan, and it has been becoming very popular.