SeaShell News, 3-11-15, Atlantic Coquina, Shelling, Boca Grande.
“Donax variabilis, common name the “coquina”, is a species of small edible saltwater clam, a marine bivalve mollusc in the family Donacidae, the bean clams. It is a warm water species which occurs in shallow water on sandy beaches of the East Coast of the USA.
The maximum reported size is 19 mm. The exterior of the small shell of this species can have any one of a wide range of possible colors, from almost white, through yellow, pink, orange, red, purple, to brownish and blueish, with or without the presence of darker rays.“
Source: Atlantic Coquina.