Sea silk embroidery on brocaded silk/linen, from the chasuble of St. Yves de Louannec, Louannec, Bretagne, France. Sea silk comes from the three-foot-tall bivalve bissus (Pinna nobilis), which lives in the waters of the Mediterranean. Sadly, the art of spinning the byssus fibres has nearly died out. Someone please save it! Chiara Vigo is the only woman in the world who still has the know-how.