Discussing carbon 14 in fossils

Can this be demonstrated directly? If, for example, the diamond emitted no electrons, then I suppose that would demonstrate it completely. But I don't suppose diamonds are bereft of all radioactive isotopes capable of undergoing beta minus decay. But perhaps it is still possible to rule out ¹⁴C as a source of the radiation by analysis of the emissions; I think this is probably the case, but I don't quite know enough about it.