Typically a date costs around $595, but sometimes special procedures are needed to guarantee accuracy. This can include collagen extraction, sample purification, and the removal of contaminants. Our dating process automatically includes macrofloral identification if it is a plant sample. We also don't just provide a date, but also context to help you interpret the information.
How does it work?
Over the course of our lifetimes, we take in 3 isotopes of carbon. The ratio of the first two - 12C and 13C - can tell us about the diet of an animal, or the drought-resistance of a plant. The third radioactive isotope, 14C, has a half-life of 5,730 years. By assessing the amount of 14C in a plant or animal, we can identify how long it has been since it last took in carbon.
There are a couple things which make this a bit more difficult. The first is that the amount of 14C in the atmosphere has change over time. Fortunately, tree rings and corals provide annual records of this variation; we can use it to calibrate our dates. An example is below.
To the right, you can see the normal distribution (e.g. smooth curve) of the 14C activity. On the bottom, you can see the modified curve that includes the variation in atmospheric 14C. As you can see, this takes on date - ~960 A.D., and shows that there are three possible dates consistent with this - 1015 A.D., 1105 A.D., 1150 A.D. It is important to remember that any radiocarbon date is a probability - not an absolute answer.