The shells of bivalves in this family are fragile and have a long and triangular shape, and in life the pointed end is anchored in sediment using a byssus.

The family Pinnidae includes the fan shell, Atrina fragilis, and Pinna nobilis, the source of sea silk.

In the Mediterranean area, material made from the holdfast or byssus of Pinna nobilis Linné has been utilized in the manufacture of clothing for many centuries: gloves, shawls, stockings and cloaks.

Apparel made from this material has an attractive golden hue and these items were greatly valued by the ancients.

Today, Pinnidae are eaten in Japan, Polynesia, in several other Indo-Pacific island groups, and on the west coast of Mexico.