Natural Puka Shell Formation
The shell of a cone snail is cone-shaped, and closed at the larger end. When the dead shell is rolled for a long time by the waves in the breaking surf and coral rubble, the narrow end of the shell breaks off or is gradually ground off, leaving only the more solid top of the shell intact.
Given enough time, the tip of the spire of the shell usually also wears down, and thus a natural hole is formed from one side to the other. This shell fragment can be considered to be a sort of a natural bead, and is known as a "puka". Real puka shells are not flat: one side of the bead is slightly convex, the other concave. The concave side of the bead clearly shows the spiral form of the interior of the spire of the cone shell.
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“I am against nature. I don’t dig nature at all. I think nature is very unnatural. I think the truly natural things are dreams, which nature can’t touch with decay.”
—Bob Dylan [Robert Allen Zimmerman] (b. 1941)
“I was even more surprised at the power of the waves, exhibited on this shattered fragment, than I had been at the sight of the smaller fragments before. The largest timbers and iron braces were broken superfluously, and I saw that no material could withstand the power of the waves; that iron must go to pieces in such a case, and an iron vessel would be cracked up like an egg- shell on the rocks.”
—Henry David Thoreau (1817–1862)
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—Ralph Waldo Emerson (1803–1882)