Coquina outcrop at dawn at Washington Oaks Gardens State Park, Palm Coast, Florida. This is the largest coquina outcrop on the Atlantic seaboard. Coquina is a soft sedimentary rock formed from shells. It's name is Spanish for shell fish. It was used a lot in construction in the past in Florida. Forts were often made of coquina because it was soft and the walls absorbed the impact of cannon balls rather than shattered.