Puka shell

Puka shells originally were naturally occurring bead-like objects which can be found on some beaches in Hawaii. Each one was the beach-worn apex of a cone snail shell, a kind of seashell from a sea snail. Puka is the Hawaiian word for "hole" and refers to the naturally occurring hole in the middle of these rounded and worn shell fragments. These natural beads were made into necklaces.

Numerous inexpensive imitations are now widely sold as puka shell necklaces. The majority of these are not made from cone shells, but from other shells, or even from plastic. In addition, some strings of beads are currently sold that are made from cone shells, but the beads in these necklaces were not formed by natural processes. They were instead worked by hand from whole shells using pliers to break the shell down to the needed part, and then subjecting the rough results to tumble finishing, in order to give each bead more or less smooth edges in imitation of the natural wear and tear a shell receives when tumbled in the surf over long periods of time.

The original all-natural puka shells were very easily made into necklaces, bracelets and anklets because they were naturally pierced, which enabled them to be strung like beads. Puka shell jewellery first became a popular item in Hawaii during the 1960s, as an attractive and inexpensive lei which could be made and sold on the beach where it was made. In the 1970s, this type of shell jewelry became highly sought after, and prices skyrocketed. The craftsmanship also became more refined and the lei pūpū puka, puka shell leis were strung in graduated or matching styles, rather than the original random patterns.

Many "legends" about the puka shell were created during this time, and these stories also helped sales.

The terminal helix of the shell of a cone snail is cone-shaped, and closed at the apex. When the empty shell is rolled over a long time by the waves in the breaking surf and coral rubble, the terminal helix of the shell breaks off or is gradually ground off, leaving the solid top of the shell intact.

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Wikipedia