Diagnosis of the conservation status of a set of lead traps from underwater origin: use of rigid agar?agar gels for their intervention
Keywords:
cepo de ancla, plomo, alteración de plomo, EDTA, agar-agarAbstract
This work offers a preliminary view of the state of conservation of a set of 87 lead stocks from the ancient times belonging to the Museum of Cadiz. The alterations identified can be divided into two main groups: those caused during the useful life of the object, such as deformations, fractures and cracks, etc., and those caused by the physical and chemical alteration of lead in the underwater environment. The abundance of surface alterations, together with the fact that a large number of the stocks studied had surface elements of great interest, such as marks of use and manufacture or decorative elements, made it necessary to carry out a diagnosis of the state of conservation of this large group of objects affected by similar pathologies.
This diagnosis served as the basis for establishing a dual conservation and restoration methodology aimed at the physico-chemical stabilisation of the objects and the recovery of documentary traces. Among the objectives of this research were the identification of the phases of alterations for which different analysis techniques were used (DRX, SEM-EDX and MO). For the subsequent selective removal of the unstable alteration products superimposed on the documentary traces, tests were carried out with rigid agar?agar and EDTA gels.
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References
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