Ragnar Saage „Metalworking Sites in Estonia during the 7th–17th Centuries”

On 11 March at 16:15 Ragnar Saage will defend his doctoral thesis „Metalworking Sites in Estonia during the 7th–17th Centuries”.

Supervisors:
Andres Tvauri, PhD (Univeristy of Tartu);
Jüri Peets, PhD (Tallinna Univeristy of Technology)
Sebastian K.T.S. Wärmländer, PhD (University of Stockholm)

Opponent:
Thomas Birch, PhD (University of Arhus)

Summary
Archaeology can contribute greatly to our understanding of past metalworking. The main goal of this thesis is to provide new information on Estonian metalworking between the 7^th–17^th centuries, based on archaeological sources. During this period there were political changes and technological developments that impacted Estonian society. The most important event was the 13^th century crusade, after which Estonia was brought into Christian Europe. Western craftsmen started to settle into Estonia with the founding of new towns, bringing new techniques and tools as they came.

My main contribution is the study of metalworking sites and the analysis of their production waste. Smithies, forges, iron blooms and bars are all investigated to gain a better understanding of ferrous metalworking. Local iron production and the scattered locations of smithies retained the pre-crusade workshop layout up until the 14^th century. The 14^th–17^th century smithy site of Käku was studied in detail and the excavations between 2007–2014 revealed the remains of four consecutive smithies and thousands of finds. The smithy of Käku more resembles the 14^th century urban smithies at Haapsalu, than the 13^th–14^th century rural smithy of Paatsa, which indicates a convergence of rural and urban smithing traditions by the 14^th–15^th centuries. Metallographic analysis of iron blooms and bars from the smithy site of Käku provides insight into how the smiths processed bloomery iron and how steel tools were reused.

The non-ferrous metalwork is studied via crucibles and casting moulds. The residue they contained was analysed with a portable spectrometer (pXRF) and a scanning electron microscope (SEM-EDS). The results show that in the 7^th to early 13^th centuries the casting of silver and tin took place at hill forts and strongholds. Silver residues were detected in 27% of the crucibles, which suggests that silver casting was common. After the crusade, the towns became the main centres for the casting and crafting that previously was undertaken in the fortified centres. Foreign craftsmen introduced imported crucibles that were more durable at high temperatures than crucibles made from local clay. A few of the studied crucibles had residues of pure gold, which indicates a higher level of specialist goldsmithing, compared to the work of pre-crusade craftsmen.