On the Effect of Salt and its Removal from the Fibers of the Wool Weavings Found with the Salt Men in Chehr Abad Salt Mine, Zanjan

Abstract

Examination of the salt men and their accompanying objects in Chehr Abad Salt Mine, Zanjan, has opened up an interesting research area for archaeologists and conservators. In addition to the historical and cultural values of these works, indicating the rich civilization of that period, investigation into the preservation and type of remaining ingredients, often putrescible organic materials, provides a rich field of research. In this case study, research was conducted on the discovered objects in Chehr Abad salt mine, with identification of the objects and hand-woven artifacts found in the mine and, more importantly, the effect of salt on the hand-woven artifacts. Since discovered artifacts are often sensitive to changes in environmental conditions, salt absorption and the role of salt as a disinfectant, are obvious factors to be considered. The discovered hand-woven artifacts are of paramount importance due to their history. They were discovered as a result of cooperation between archaeological teams working in Iran and Germany (from the Bochum museum and University). As these weavings were soaked in minerals and other wastes, the cleansing procedure was done by water washing. In order to protect the weavings, unearthed and removed from their original site of discovery, research on issues such as the removal and retention of salt, its impact on the life-span of organic materials, the probability of the hand-woven fibers being destroyed by salt crystals and the reaction of water and salt, all needed to be considered. In this paper an introduction is given to the discovered objects and artifacts from Chehr Abad salt mine, with a study of the wool fibers, examined by visual (macroscopic) inspection, optical micrographs, electron SEM micrographs, including an EDX analysis of the hand-woven artifacts. The results of the investigations have shown the conservative effect of the salt on the fibers.