What does coquina mean?
Coquina is a soft, highly porous sedimentary rock formed almost entirely of broken shells and coral fragments lightly bound together with calcium carbonate, giving it the appearance of natural concrete made of seashells. Because it is easy to quarry yet remarkably durable in a marine climate, it has been prized as a building material since the late seventeenth century, most famously at the Castillo de San Marcos in St. Augustine, Florida — a fortress whose spongy coquina walls absorbed rather than shattered incoming cannonballs. Separately, along the Atlantic and Gulf coasts of the southeastern United States, 'coquina' also names a tiny, colorful wedge-shaped clam (genus Donax) that washes up in swarms on sandy beaches and is sometimes collected for broth. Both senses trace to the Spanish word for 'cockle,' reflecting the region's Spanish colonial heritage. The word thus evokes sunlit shorelines, historic masonry, and the humble abundance of the intertidal zone.
A soft, porous limestone consisting of loosely cemented fragments of shells and coral.
"The seawall was faced with blocks of coquina that weathered to a honeyed gold."
Often capitalized informally when referring specifically to the Florida building stone.
A small edible marine clam of the genus Donax, abundant on sandy beaches of the southeastern United States.
"She steamed the fresh coquinas with garlic and white wine."
Plural form commonly used for the clams themselves.
The plural applies naturally to the clams; for the rock, the uncountable singular is usual unless referring to distinct deposits or varieties.
"Waves left thousands of coquinas scattered across the sand."
Cannonballs fired at St. Augustine's Castillo de San Marcos didn't break through its coquina walls — they just bounced off or got swallowed by the spongy shellstone.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of coquina
Coquina was borrowed directly from Spanish, where it means 'cockle' or 'cockleshell'; the Spanish word derives from Latin concha, the same root behind English 'conch,' 'cochlea,' and ultimately 'cockle.' The English geological use arose during the colonial period in Florida, where Spanish builders first exploited the shellstone, and the name for the little Donax clam followed the same path. Its lineage ties it firmly to the Spanish-speaking Caribbean and Florida coast.
How coquina is actually used
In American English, especially in Florida and the Carolinas, 'coquina' refers to both the building stone and the beach clam, and both uses are well established. The geological term appears mainly in technical or regional writing; the clam use is familiar to coastal residents and cooks. The word carries a distinctly regional, coastal flavor.
Easily confused with coquina
Cochineal is a red dye derived from scale insects, whereas coquina is a shell-based limestone or a small beach clam.