In addition to their economic value as food, mollusks are also used to make jewelry the most notable and valuable example of which is pearl jewelry. While clams, oysters, snails and squid frequently contribute to many coastal economies as food sources, the shells of various mollusks have also been used as a form of currency at times throughout history.
China is a leader in the worldwide mollusk catch and reached an 80 percent global share in 2005. France is the industry leader in the European catch. The pearl industry has become a vital part of some countries economies, and significant sums of money are allocated to the monitoring of the health of mollusks produced on farms.