[from occupied ga]

You really missed class the day they covered C14 dating didn't you. The whole point is that c14 is constantly created by natural processes cosmic rays mostly and promptly begins decaying so we reach what is called a "steady state" for C14 in the environment where the rate of formation equals the rate of decay.

When something dies it becomes isolated from c14 uptake - dead things don't eat. So the steady state level of c14 begins to decay at the ~12,000 year half life. An artifact with half the environmental norm of c14 is 12k years old. One with 1/4 the steady state is 24k years old etc.

[calenel]

Mostly right - except you got the half-life wrong. It’s in the ball park of 5750 years. That’s one of the things that makes it so useful, its half-life is roughly the same duration as recorded human history.