The coral is converted to sand by internal bioeroders such as algae, fungi, bacteria (microborers) and sponges (Clionaidae), bivalves (including Lithophaga), sipunculans, polychaetes, acrothoracican barnacles and phoronids, generating extremely fine sediment with diameters of 10 to 100 micrometres.
In particular, the town of Pozzuoli features the Roman Macellum of Pozzuoli in which three marble columns show bands of boreholes or Gastrochaenolites left by marine Lithophaga molluscs.
The Macellum includes three majestic columns in cipolin marble, which show erosion from marine Lithophaga molluscs when, at an earlier time, the ground level was much lower due to Bradyseism, and sea-water could flow in.