Seashells belong the kingdom Mollusca. Most Mollusca are soft fleshy slug like creatures that have a hard external skeleton type structure to help protect them. Mollusca can be found in both salt and fresh water, as well as on the land (snails). In the oceans, this structure is known as a seashell.
I wanted to know more about these particular shells, so I searched the Internet and found a seashell identification guide. So far I’ve identified (or misidentified) a Florida Auger, Scotch Bonnet, Shark Eye or Moon Snail, Pecten Raveneli and possibly a Jingle (not pictured).
Taking the children to beach comb or simply watch the waves is always a lot of fun. Incorporate Islaamic Studies in your trip by reading a short passage of Tafseer about this (or a related aayah):
“And it is He Who has let free the two seas (kinds of water), one palatable and sweet, and the other salt and bitter, and He has set a barrier and a complete partition between them. “