What can radiocarbon dating date
When it comes to dating archaeological samples, several timescale problems arise.
For example, Christian time counts the birth of Christ as the beginning, AD 1 (Anno Domini); everything that occurred before Christ is counted backwards from AD as BC (Before Christ).
Radiocarbon is then taken in by plants through photosynthesis, and these plants in turn are consumed by all the organisms on the planet.
The numbers refer to the atomic weight, so Carbon-12 has 6 protons and 6 neutrons, Carbon-13 has 6 protons and 7 neutrons, and Carbon-14 has 6 protons and 8 neutrons.
As long as there is organic material present, radiocarbon dating is a universal dating technique that can be applied anywhere in the world.
It is good for dating for the last 50,000 years to about 400 years ago and can create chronologies for areas that previously lacked calendars.
The Mayan calendar used 3114 BC as their reference.
More recently is the radiocarbon date of 1950 AD or before present, BP.The Greeks consider the first Olympic Games as the beginning or 776 BC.The Muslims count the Prophet’s departure from Mecca, or the Hegira, as their beginning at AD 662.Shellfish remains are common in coastal and estuarine archaeological sites, but dating these samples require a correction for the “reservoir effect” a process whereby "old carbon" is recycled and incorporated into marine life especially shellfish inflating their actual age in some cases several centuries.