The section of the site provides an archive for information on GeoArch’s experimental work between 1998 and 2009. This information is being been ported across from the old GeoArch website – a process that may take some time, so there may be broken links.

Iron Smelting

A programme of experimental work has been undertaken,
based in the National History Museum, St Fagans, near Cardiff (a branch of Amgueddfa Cymru – National Museum Wales). The experiments were conducted in a workshop adjacent to the Celtic Village. The experiments were run on an occasional basis from 1998 to 2004. The programme was designed to investigate the smelting, in a large slag-tapping bloomery furnace, of oxide iron ores, of the kinds exploited in the region in early times. The furnace was a reconstruction of what is believed to be the typical type of furnace used in the area throughout the first millenium AD.

Smelt 3 pre-heat
Smelt 3 pre-heatSmelting experiments are trying to reconstruct the methods of operating a large slag-tapping furnace. The furnace is seen here in an early form, in June 1998.

Since then, three smelts were undertaken away from Cardiff – one for the Four Parishes Heritage Group (smelt 28), one at the UCL Primtech event (smelt 29) and one for the 6th International Conference on Contemporary Cast Iron Art (smelt 30).

The furnace was left uncovered after its last use in March 2004; its fate was monitored and formed a part of the experiment. By December 2005 the blowing wall was still fairly intact, but much of the rest had collapsed. The remains then became quite stable, but the site was redeveloped in 2014.



Experimental Brazing

Experiments to reconstruct an Early Christian handbell were undertaken during 2007/8, with further experiments into early brazing techniques being undertaken in 2009. Summaries of these three campaigns of experiments are being made available on this website. Further information on the 2009 experiments can be found on the National Museum Wales blog.

Brazing outside St Teilo's church
Brazing outside St Teilo’s church



1998 smelting campaign
1999 smelting campaign and 1999 charcoal burning
2000 smelting campaign
No smelting was undertaken in 2001 following storm damage
2002 smelting campaign
2003 smelting campaign
2004 smelting campaign
2007 smelting campaign
2010 smelting campaign

List of all smelting experiments with their operating parameters.

This research has only been possible through the hard work of many people, to whom I owe great thanks