Sagnlandet Lejre: THE MAP OF BOG IRON

Period: Iron Age (500 BC - 700 AD)

Project titel: Forsøg med herkomst af dansk myremalmsjern

Forsker: Henriette Lyngstrøm, Lecturer, Archeologist, Copenhagen University

Year: 2008

Abstract:

Approximately 2500 years ago Iron production began in Denmark. Danish Iron is won from ores of bog iron, which is to be found in natural deposits all over the country. Archaeological evidence of local iron production has also been found, as ovens for the winding of iron have been discovered on both Zealand, Fynen and Jylland. Iron as a resource was in high demand in prehistoric times, but which part did home-made iron play in Iron Age society and development?
Scientific research in recent years has shown, that only small amounts of home-made iron was produced. The theory is that iron production more or less only took place on a household basis, so that the needs of the farm or village was satisfied, but the iron was not produced for trading purposes. An iron knife produced locally was also used locally. A knife was a personal tool and often ended up in the graves with their owners. But how can you tell by looking at a knife, where it was produced?

Archaeologist Henriette Lyngstrøm has shown that microscopic analysis of bog iron in prehistoric iron knives can reveal which part of the country the iron ore derives from, and thus pinpoint the local origin of the raw materials. By applying this method we may be able to decide whether iron was consumed locally or traded. In other words we will be able to follow in the footsteps of iron objects - and hence their owners - across the country in spite of the fact they lived and died 2000 years ago.

The experiment is to produces samples of bog iron from many different regions in Denmark, so that the iron from each region might be identified and compared with original objects from the Iron Age. Experiments from previous years have analysed bog iron from different parts of Jylland. This year bog iron from Zealand will be won. First an Iron smelting oven will be built, the iron carefully extracted and lastly knives will be forged from the raw iron, while the processes are being documented and analysed.

Reference number HAF 17/08

Project title: Forsøg med herkomstbestemmelse af jerngenstande

Researcher: Henriette Lyngstrøm, lecturer, Copenhagen University, Denmark

E-mail: lyngst(at)hum.ku.dk

Year: 2001

Abstract:

The starting point for these experiments was a desire to be able to identify the origins of iron artefacts. The experiments involve the description of the chemical and physical changes in slag inclusions from ore to finished tool. The whole process from ore to finished tool is carried out. During the process, samples are taken from ore, bloom, extraction slag, bar/ingot, cleaning slag, tools and smithing slag. The experiment is the second in a series of three. Knowledge that has been built up through more that 10 years of experiments with iron smelting and smithing at Lejre Experimental Centre was collected, used and assimilated. The second part of the experiment comprised roasting and cleaning of bog iron ore from Guldforhoved and Store Dyrehave.

Reference number: HAF 07/01