Page 201 - Manual for Activities directed at the Underwater Cultural Heritage
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responsible for the collection. Finally, application of a protective coating (of wax, varnish or resin) suited to the future exhibition site – interior or exterior – will help preserve the objects for the foreseeable future.
Conservation and restoration treatments are carried out using both traditional and technically advanced technologies. They are often long- term, ranging from several months to several years. This is particularly true for the processes related to the stabilization.
 Metals: Treatments focus mainly on stabilizing cor- rosion by removing the chloride ions. For larger or more chloride-contaminated objects, the most effective means of achieving that end is through electrochemical treatment by chemical solutions. Electrolysis is used to clean concretions on cannon, anchors and other large metallic objects. Electric current from the power sup- ply will either help remove concretions by causing hy- drogen micro bubbling on the object’s original surface, or will spark chemical changes in corrosion products (reduction) that speed up the removal of chloride ions. Electrolysis also helps remove chlorides and surface corrosion products from non-conductive organic mate- rials, ceramics, etc.
Mineral objects: Controlled air-drying or a consolida- tion treatment, depending on their conservation condi- tion, follows salt removal which begins by simple im- mersion in fresh water. Consolidation treatments entail a number of immersions in specific chemicals followed by gradual, controlled drying.
Organic materials: Stabilization treatments seek to pre- vent any sudden drying of the object or contact with air that might cause shrinkage or deformation. Two types of treatment are known to stabilize organic objects: gradually replacing water in the pores with various concentrations of polyethylene glycol (PEG) followed by natural smooth drying or freeze-drying, or the ARC- Nucléart method which consists of rinsing the objects in an acetone solution, impregnating wood with a polyes- ter-styrene resin and polymerizing the resin by exposing it to gamma radiation.
Lithic materials: Stabilization treatment mainly con- sists of simple rinsing procedures by immersing the ar- tefacts in fresh water.
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Conservation and site management



























































































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