Coquina rock is quarried or mined and has been used as a building stone in Florida for over 400 years, Coquina forms the walls of the Castillo de San Marcos, in Saint Augustine. The stone makes a very good material for forts, particularly those built during the period of heavy cannon use. Because of coquina's softness, cannon balls would sink into, rather than shatter or puncture, the walls of the Castillo de San Marcos.
When first quarried, Coquina is relatively soft. This softness makes it very easy to remove from the quarry . In order to be used as a building material, the stone is left out to dry for approximately one to three years, which causes the stone to harden into a usable stone, but will still be considered a comparatively soft stone.
Large pieces of Coquina of unusual shape are sometimes used as landscape decoration. Because Coquina often includes a component of phosphate, it is sometimes mined for use as fertilizer.