珍珠 分天然和人工养殖两种。天然珍珠是海水和淡水蚌科动物。因偶然有细小沙粒进入到蚌壳内,引起蚌科动物分泌真珠质包裹沙粒,天长日久而形成珍珠。人工珍珠是将沙粒和蚌壳做成小粒,放入蚌贝的壳内,三年后即可得到珍珠。 Pearls are divided into two types, natural and artificial. Natural pearls are seawater and freshwater stork animals. Due to accidental small sand particles entering the oyster husk, it caused the pupa family to secrete nacre-coated sand, which formed pearls as time went by. Artificial pearls are made of small grains of sand and oyster shells and put into shells of mussels. Pearls can be obtained after three years.