Brief introduction of shells
Shells are shells of molluscs living near the water, and they are calcifications secreted by special gland cells of molluscs, which are used to protect soft parts of the body. Compared with natural calcium carbonate minerals in nature, shells have a unique multi-scale and multi-level assembly structure, and have excellent characteristics such as good toughness and high strength because of their multi-level layered structure. Shells are also widely used, such as the shells of shellfish such as clams. Some have pearl-like iridescent luster, so they are used in jewelry industry, making necklaces, clothing accessories, and even installed on jewelry, and more are used to make shell carvings, collages, inlaid handles, etc.