Tropical seashell scarf holder slides for ladies scarves, sarongs

Lot of tropical beach sea shells made into slide type 'buckles' to hold scarves (or sarongs!) in place. These are really lovely large seashells, the largest is 4" long.

The loops at the back are some sort of clear acrylic or plastic epoxy.

These are 80s vintage, in a little sea grass basket of about the same vintage I think? Very 'South Pacific' style, though this set is probably from the Philippines, really.