Explanation

A clay rock with complex composition and thin sheet or sheet bedding. It is formed by clay after consolidation, compaction, dehydration, hardening or recrystallization. The main composition is clay mineral. Most clay mineral have transformation into water mica, often containing different amounts of mixed figures, such as quartze, feldspar debris, fine rock debris, chemical origin materials, organic matter, etc. The appearance is earthy and has regular page patterns, which can be formed into thin sheets by tapping with a small hammer. Colors include green, yellow, reddish brown, etc. According to the mixed impurities or rock color, it can be divided into calcareous, ferrous, siliceous shale, carbonaceous shale, black shale, oil shale, silty shale, etc. Some clay mineral have high content and poor curing strength. They can be used as raw materials for coarse pottery and ordinary bricks after simple crushing. It can also be used as the raw material for firing ceramsite and the ingredient of cement.

Classification