Most marine animals form their shells from calcium carbonate, which is a tough mineral also found in limestone. Some sponges ...

Seashells are the abandoned exoskeletons of mollusks, like snails and clams. Numerous seashell varieties, including ark shells, scallops and conchs, can be found on Corpus Christi beaches, ...

Seashells tend to appear quietly. After the tide pulls back, they are just there, mixed into the sand, sometimes whole, ...