Category: seashells...

If seashells are kept in the light too long, they fade.
most seashells are formed from substances secreted by the mantle, a skinlike tissue in the body wall
seashells are collected for their endless diversity, elegance of form, and bright colors
in ancient times, some varieties such as tooth shells and cowrie shells were used as money
collecting exotic shells on the beaches of Sanibel and Captiva islands
a pearl is often hidden in an ugly shell
seashells are often made up of several layers of distinct microstructures, like nacre (mother-of-pearl)
the mollusk is bound securely to its shell and generally cannot survive separation from it
I have seen A curious child, who dwelt upon a tract Of inland ground, applying to his ear The convolutions of a smooth-lipped shell, To which, in silence hushed, his very soul Listened intensely; and his countenance soon Brightened with joy, for from within were heard Murmurings, whereby the monitor expressed Mysterious union with his native sea. William Wordsworth)
Little minds mistake little objects for great ones, and lavish away upon the former that time and attention which only the latter deserve. To such mistakes we owe the numerous and frivolous tribe of insect-mongers, shell-mongers, and pursuers and driers of butterflies, etc. The strong mind distinguishes, not only between the useful and the useless, but likewise between the useful and the curious. (Philip Dormer Stanhope, 4th Earl Chesterfield)