A shell purse is a type of coin purse that is made from whole or trimmed mollusk shells, especially from bivalve mollusc shells. These purses are of mainly novelty use and purchased as souvenirs of visits, etc. In the past, some were engraved or painted with floral or other decorations, sentimental messages, personal or place names. In many cases there was extra working of the shell, either grinding down and polishing to expose the mother of pearl or filing to form patterns such as criss-cross designs.