However, Bailiff is a bit sceptical about the reliability of historic temperature records.“The devil is likely to be in the detail – the chronometric mechanism is temperature dependent, and much work may need to be done to obtain calibration data.” The researchers are now planning to test whether their dating technique can be applied to earthenware, bone china and porcelain.Researchers in the UK have created a new way of dating archaeological artefacts that involves heating ancient pots to unlock their internal clocks.The relatively simple technique could become as important for dating ceramics as carbon dating is for organic materials, say the researchers at the Universities of Manchester and Edinburgh.A big breakthrough came in 2003 when the researchers realized that this process has occurred at a predictable rate throughout history, related to temperatures.Now the researchers have turned their theory into a practical dating method and present their findings in Proceedings of the Royal Society A.
The researchers established that the rate at which ceramic materials gain extra water in this process obeys a (time) power law.
The team has already dated ceramics from the Roman, medieval and modern periods to a high degree of accuracy, and they are now looking to establish a global research facility for the technique.
The method relies on the fact that fired clay ceramics — like bricks, tile and pottery — start to chemically combine with water as soon as they are exposed to the atmosphere.
They calculated that the rate of reaction is independent of atmospheric moisture levels but is governed by the ambient temperature averaged over a ceramic’s lifetime.
The dating procedure involves measuring the mass of a sample of ceramic and then heating it to around 500 degrees Celsius in a furnace, which removes the water.
Perhaps the most significant feature of this new water-based technique is that — as with radiocarbon dating — it is self-calibrating, based on rehydroxylation alone.