Marine mollusk shells that are familiar to beachcombers and thus most likely to be called seashells are the shells of marine species of bivalves (or clams), gastropods (or snails), scaphopods (or tusk shells), polyplacophorans (or chitons), and cephalopods (such as nautilus and spirula).

Also, where do spiral shells come from? Most seashells come from mollusks, a large group of marine animals including clams, mussels, and oysters, which exude shells as a protective covering. Shells are excreted from the outer surface of the animal called the mantle and are made up of mostly calcium carbonate.

Also question is, what is spiral shell?

Spiral shell. any shell in which the whorls form a spiral or helix.

What is the symbolic meaning of a seashell?

Along the coastlines of the world, a great variety of shells can be found. Seashells are made by the animals that live inside them and all shells grow steadily outward. Shells are usually perceived as feminine; a symbol of birth, good fortune, and resurrection. Bivalved mullusks represent the womb and fertility.