Archaeological iron objects

Treatment of iron objects from the Born market site by means of hot alkaline sulphite baths to accelerate the process.

Management and coordination: Lídia Font, Anna Lázaro and Carla Puerto, of the Preventive Conservation and Restoration Service of the Museum of the History of Barcelona
Restorers: Ana Isabel Citores and Marta Golobardes
Laboratory analysis: Arte-Lab, SL
Year: 2009-2010

Iron objects of the Born site

Archaeological iron objects before treatment in sulphite baths. (©MUHBA)

Study of the stratigraphy of the alteration products. (©A.Citores-M.Golobardes-MUHBA)

Creation of rigid supports with Dynacast Extra® (glass-fibre bandage impregnated with polyurethane resin). (©A.Citores-M.Golobardes-MUHBA)

Three baths, each one lasting 4 weeks, were applied, in a solution of 6.3 g Na2SO3 (0.05 M) + 4 g NaOH (0.1 M) per litre of demineralised water. (©MUHBA)

Hermetically-covered tray with two stirrers-heaters to keep the solution in constant movement at 55ºC. (©MUHBA)

Temperature, chloride content, pH and iron conductivity are monitored and measured periodically. (©MUHBA)

Neutralisation with demineralised water at 55ºC using stirrers. Three changes of water over the course of 6 days, plus verification of salinity and pH. (©MUHBA)

Examples of before and after the treatment. (©A.Citores-M.Golobardes-MUHBA)
 

Examples of before and after the treatment. (©A.Citores-M.Golobardes-MUHBA)