A hydration and metamorphic transformation of ultramafic rock from the Earth's mantle is called as serpentinization, a group of minerals is formed by serpentinization compose rock 'serpentinite'.
Coquina is a sedimentary rock that is composed either wholly or almost entirely of the transported, abraded, and mechanically-sorted fragments of the shells of molluscs, trilobites, brachiopods, or other invertebrates