What about Sea Shells?
Mollusks are invertebrate animals (think of a snail) with an unsegmented, basically symmetrical body, generally consisting of head, foot, visceral hump and mantle. Mollusks are descendants from primitive wormlike creatures inched around in the ooze of primeval seas millions of years ago. As dissolving land masses began to feed salts and chemicals into oceans, the first mollusks digested them and eventually used them to build durable shelters.
Abalone are marine snails. Their taxonomy puts them in the family Haliotidae which contains only one genus, Haliotis, which once contained six subgenera. These subgenera have become alternate representations of Haliotis.
The shells of abalones have a low, open spiral structure, and are characterized by several open respiratory pores in a row near the shell's outer edge. The thick inner layer of the shell is composed of nacre (mother-of-pearl), which in many species is highly iridescent, giving rise to a range of strong, changeable colors, which make the shells attractive to humans as decorative objects, jewelry, and as a source of colorful mother-of-pearl.
The flesh of abalones is widely considered to be a desirable food, and is consumed raw or cooked in a variety of cultures.