How to identify a seashell

Updated July 20, 2017

No collection is complete without proper the identification and labelling of all specimens. Knowing the correct species of your seashells allows you to keep a diverse collection and to observe the differences between shells of the same type. Seashell collecting is a simple activity that complements spending a day at the beach and lets you know about the types of life that live where you swim, along with getting you off the beach blanket and down the shore for a walk.

Clean your shell thoroughly inside and out. Remove as much dirt and growth from the shell as possible.

Record where you found the seashell. Note the beach, the ocean or other body of water that it borders and the city or town that the beach is near. This will help you understand what types of shells you may expect to find in specific areas. For example, the Fighting Conch is typically found in the southern United States near "shallow grassy bays," according to

Measure the length of the shell. Small seashells are about ¼ to 2 inches long, medium-sized shells are about ¾ to 4 inches and large shells are typically larger than 3 inches. The Fighting Conch is usually classified as a large shell because it grows up to 3 inches in length.

Examine the seashell's shape. Seashells are divided into two basic categories: univalves and bivalves. Univalves are shells with one opening, such as the Fighting Conch, while bivalves have two pieces of shell hinged together at their narrowest point, such as mussels and clams.

Locate and identify distinguishing markers on the shell. Such markers may be specific colouration patterns, iridescence, spires, texture, shell thickness and unusual formations. The Fighting Conch comes in a variety of colours, such as orange, pink and white, has a distinctive cone-shaped spiral at one end, has a fine point on the other end and a large lip opening along one side. Some features may be caused by the environment, previous violence in the life of the animal and exposure to the sun or beach.

Classify your shell. Seashell types fall into six classes of mollusks, but the most common are gastropods, univalve animals, such as snails and limpets, and bivalves, such as clams, mussels and oysters. Other types of seashells include chitons, squid, octopus and tusk-shaped shells. Many books and websites offer pictures and additional information that help with classification; some are linked in the References and Resources sections.


Always use complete shells for identification purposes. Seashells are defined only as the carapace of mollusks, and animals such as crabs, starfish and sand dollars may not be referenced in some shell guides.


Do not to overcollect; one of each type of seashell is enough to ensure a diverse and interesting collection. Never take a seashell with a live animal inside. Some of them are endangered or protected species.

Things You'll Need

  • Ruler or measuring tape
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About the Author

Living in Montreal, Angelina Leggo has been writing since 2002, when she was published in her local newspaper. Now, her articles appear on eHow. As an honors student, Leggo is studying cultural anthropology and Canadian history at Concordia University.