Wholesale Capiz Shells in Bulk, windowpane oyster shells, a white flat seashell, measuring approximately 1-1/2 inches. The windowpane oyster is a bivalve marine mollusk in the family Placunidae used to make capiz wind chimes, inlaid furniture, placemats and in other seashell crafts.  They are edible, but valued more for their shells.  Capiz shells have been used for thousand of years as a glass substitute because of the durability and translucence.