Dating iron artefacts
Objects are preserved in peatlands because of the acidity of peat and the anaerobic environment (i.e.
deficiency of oxygen) which exists within peatland deposits.
When in the mid-1980's I wrote my own contribution to the problem, in two chapters of a book entitled Iron and steel in ancient China, the available archaeological material appeared to provide a moderately clear picture. Several artefacts of meteoritic iron from the late Shang and early Western Zhou found in north China seemed to be irrelevant to later developments; and if one ignored claims that were not properly documented with archaeological and metallurgical details, it seemed that in China the smelting of iron from ore began, as Huang Zhanyue had suggested, in the south, sometime before the beginning of the fifth century BC.
I felt, however, that I could narrow this further, to the state of Wu. From there it spread within a century to the other major southern state, Chu, and within another century to the rest of the Zhou empire, almost entirely replacing bronze as the metal of choice for most practical implements and weapons.
Historical records had placed the age of the crown between the late Roman and middle Ages, a spread of some hundreds of years.
Carbon dating is the most accurate means of dating ancient artefacts, but the materials used in the crown - gold, a strip of iron, a nail reputedly from the True Cross, and precious stones - are non-biological and therefore cannot be dated using this technique.
The solution Samples of less than a milligram were sent to ANSTO for radiocarbon dating at the ANTARES (Australian National Tandem for Applied Research) tandem accelerator.
During the Industrial Revolution, new methods of producing bar iron without charcoal were devised and these were later applied to produce steel, creating a new era of greatly increased use of iron and steel that some contemporaries described as a new Iron Age.The use of wrought iron (worked iron) was known by the 1st millennium BC, and its spread marked the Iron Age.During the medieval period, means were found in Europe of producing wrought iron from cast iron (in this context known as pig iron) using finery forges.Such locations were used by early communities for camping (Mesolithic site, Lough Boora, Co.Offaly) or for farming (Neolithic site, Ceide Fields, Ballycastle, Co. These sites had to be abandoned due to waterlogging and the early formation of peat.
Search for dating iron artefacts:
In 1953 there was another major find, the site of an iron foundry of the third century BC in Xinglong County, Hebei, where cast-iron moulds for casting iron implements were found.