Report on field work by Dr Ian MacLeod

National News Categories: 
Publish date: 
10 Sep 2019
Author: 
Ian MacLeod and Alice Paterakis

Ian MacLeod conducting in-situ measurements for the Japanese Institute for Anatolian Archaeology. Photo by Alice Paterakis

As Europe sweltered, the Kaman-based Japanese Institute for Anatolian Archaeology breathed a collective sigh of delight with temperatures in the high 20s rather than the high 30s, which made work in the field and in the un-conditioned conservation laboratories very pleasant. Experimental work on freshly excavated bronzes dating back to over 3,400 years BP showed that a strong indicator of underlying bronze disease could be picked by using the 3-minute pH measurement of objects placed in 100 ml of the neutral electrolyte solution of 0.05M NaNO3. Chloride and pH monitoring over 36 hours showed the impact of the alkaline soils and the presence of high levels of chloride within the corrosion products deep in the heart of the objects.

A presentation was given at the two-day conservation seminar at the Institute that had been organised by Dr Alice Paterakis, the director of conservation in Kaman. The topics all related to archaeological conservation and a publication of the conference proceedings will be forthcoming. The works demonstrated that it is possible to obtain useful Eh, pH and chloride measurements on the soils, which provide an identikit picture of the corrosion microenvironment in which the objects are found. A combination of burial depth and presence of dissolved salts and iron minerals in the clay-rich soils provided clues to understanding the present and future conservation needs of the collection. Field measurements at the Kaman-Kalehöyük site confirmed decay mechanisms gleaned during the initial 2017 studies.