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1. Pan-Alkali: Pan-Alkali is a white crystalline substance left on the surface of the stone by the moisture which frees the alkali, salt and other substances contained in the stone itself and the binding material along the pores and seams of the stone. In the design process, the phenomenon of stone pan-alkali should be considered in advance.

2. Corner treatment: The corner stone specifications should be unified with the surrounding stone specifications. The corners of the building's yin and yang corners should be targeted to cut the stones. Special corners can be used with non-standard edge stones to ensure the effect.