After death the amount of carbon-14 in the organic specimen decreases very regularly as the molecules decay.
Carbon-14 has a half-life of 5,730 ± 40 years, meaning that every 5,700 years or so the object loses half its carbon-14.
Radiocarbon dating involves determining the age of an ancient fossil or specimen by measuring its carbon-14 content.
Right: A crushed ammonite from the Shales-with-Beef Member, found on the foreshore beneath Black Ven.
Left: A large nautilus in cross-section on the surface of a foreshore boulder at Monmouth Beach, beneath Ware Cliffs. Norman Mac Leod and Dr Paul Davis at the Natural History Museum of London for their continued support and guidance identifying the stratigraphy of Black Ven and Church Cliffs.
Samples from the past 70,000 years made of wood, charcoal, peat, bone, antler or one of many other carbonates may be dated using this technique.
Instead, other methods are used to work out a fossil’s age.
These include radiometric dating of volcanic layers above or below the fossils or by comparisons to similar rocks and fossils of known ages.