Introduction to slate

The hardness of the original rock is enhanced due to dehydration, but the mineral composition is basically not recrystallized, with residual structure and residual structure. The appearance is dense cryptocrystalline, and the mineral particles are very fine, which is difficult to distinguish with the naked eye. There is often a small amount of sericite and other minerals on the plate surface, which makes the plate slightly show silk luster. Slate can generally be named in detail according to different color impurities, such as black carbonaceous slate and gray-green calcareous slate. In low-grade thermal contact metamorphism, shallow metamorphic rocks with spotty structure and plate-like structure can be formed, commonly known as "spotted rocks". Slate can be used as building materials and decorative materials. In ancient times, it was often used as tiles in areas rich in slate.