Mantle tissue that is located under and in contact with the shell secretes proteins and mineral extracellularly to form the shell. Think of laying down steel (protein) and pouring concrete (mineral) over it. Thus, seashells grow from the bottom up, or by adding material at the margins.

Where do conch shells come from?

– Conchs are native to the coasts of the Caribbean, the Florida Keys, the Bahamas, and Bermuda.

How Long Does It Take a conch shell to form?

A conch develops into an adult after about 4 years, and as it matures the mantle (body) of the snail pushes on the growing shell, making the opening flare out. This allows the mature snail to move along with lagoon floor the shell opening flat against the bottom. The conch’s rapid growth slows after the snail matures.