I'm afraid we've already exhausted the list of mollusks mentioned in the
Bible.  Congratulations, Paul, for getting the slug.  Purple is mentioned in
several places but Lydia's work as a maker and seller of the dye is the most
obvious.  And pearls, the pearl of great price, etc.  Since all marine
mollusks were unclean, we need not expect to find much notice taken of them.