This is true shell art, as even the pin dish (which could hold any other small items) is made from a shell—an oyster shell with a lovely mother of pearl surface. Other shells include a cowrie shell, clam shells and a conch shell that is hand painted with a palm tree. The shells are set into a chalkware base which makes them appear to be set in sand.
These shell art pieces were often sold as souvenirs, with the name of the city, state or other area lettered on them. This example has no such identifier, but given the palm tree decoration could be from Florida, Hawaii or the Caribbean.