What is the relative age of coquina rock according to the geologic time scale?
Can't really tell just by finding this kind of rock.
Coquina (/koʊˈkiːnə/) 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. So, it can be found in just about any geological time period from about the Cambrian to the present - in other words, the past 550 million years or so.
About all we an say is that it is younger that the Pre-Cambrian, i.e.. less than 550 million years old.