Pärlbildning
Pärlbildning, also known as pearl formation, is a natural process by which mollusks, such as oysters and mussels, create pearls. The process begins when a foreign particle, such as a grain of sand, becomes lodged in the mollusk's mantle, the tissue that lines the shell. The mollusk responds to the irritant by secreting layers of nacre, a strong, iridescent material composed of calcium carbonate and conchiolin, a protein. These layers are deposited around the foreign particle, gradually building up to form a pearl. The size and quality of the pearl depend on the size and nature of the irritant, as well as the species of the mollusk and the environmental conditions. Pearls are valued for their beauty, durability, and rarity, and are often used in jewelry and decorative items. The process of pärlbildning is a fascinating example of nature's ability to create beauty and complexity from simple beginnings.