by Helen Fryman Question: What about radiocarbon dating? Response: I asked several people who know about this field. (1.) C14 dating is very accurate for wood used up to about 4,000 years ago.This is only because it is well calibrated with objects of known age.In last Tuesday’s lecture, radiocarbon dating was covered briefly.It is an essential technology that is heavily involved in archaeology and should be explored in greater depth.
For object over 4,000 years old the method becomes very unreliable for the following reason: Objects older then 4,000 years run into a problem in that there are few if any known artifacts to be used as the standard. The method was developed by Willard Libby in the late 1940s and soon became a standard tool for archaeologists.Libby received the Nobel Prize in Chemistry for his work in 1960.They arrived at this conclusion by comparing age estimates obtained using two different methods - analysis of radioactive carbon in a sample and determination of the ratio of uranium to thorium in the sample.In some cases, the latter ratio appears to be a much more accurate gauge of age than the customary method of carbon dating, the scientists said.