Young Brunette Girl Reveals Her Seashell Necklace And Tan Lines In The Sand On The Rocky Beach

Empty seashells are often picked up by beachcombers, and collecting these shells is a harmless hobby or study. However, the majority of seashells which are offered for sale commercially have been collected alive (often in bulk) and then killed and cleaned, specifically for the commercial trade. This type of large-scale exploitation can sometimes have a strong negative impact on local ecosystems, and sometimes can significantly reduce the distribution of rare species.
Molluscan seashells
The word "seashells" is often used to mean only the shells of marine mollusks. 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). These shells are very often the most commonly encountered, both in the wild, and for sale as decorative objects.