What is a Seashell?

Seashells are the hard, protective exoskeletons of marine mollusks like snails, clams, scallops, and whelks—ocean-dwelling creatures that build and live in their shells for protection and support. When the animal dies or is eaten by a predator, the empty shell is often carried to shore by waves and tides, becoming a beautiful keepsake for beachcombers. These shells are mostly made of calcium carbonate, formed layer by layer as the mollusk grows, and often strengthened with natural proteins that add durability.

What makes seashells especially fascinating is their incredible variety and precision. From perfectly coiled spirals to delicate fans and ridged cones, each species creates a shell with a specific shape and pattern passed down over millions of years. Some mollusks have been making nearly identical shells since the age of the dinosaurs. Shell coloration and pattern can serve purposes too—like camouflage or deterring predators—and are influenced by the mollusk’s diet and habitat.

Seashells aren't just beautiful—they're also remarkably strong. Engineers and architects study their structures for inspiration, drawn to the way shells combine beauty, function, and resilience. Because they’re created slowly and naturally, each one tells a story of survival, adaptation, and deep ocean rhythms. It’s no wonder shells are often seen as symbols of independence, strength, and timelessness.

On our shelling tours around Marco Island and the Ten Thousand Islands, most of the shells you’ll find are naturally empty and just waiting to be discovered—each one a small wonder of the sea.