Page 198 - Manual for Activities directed at the Underwater Cultural Heritage

 © UNESCO. A scientist recording with a FARO Arm the structural elements of the hull
of a Byzantine ship excavated from the commercial harbour
of Theodosius,Yenikapi-Istanbul, Turkey.
Using a special computer aided design programme a 3D model can be established on the basis
of these recordings.The number of ships excavated during the archaeological operation posed an immense conservational challenge.
© National Museum of Underwater Archaeology. ARQUA. Lyophilization in the wood laboratory of the ARQUA museum in Cartagena, Spain.
A process of simply drying by evaporation can have catastrophic results on archeological leathers and woods saturated with water. Instead, a combination of chemical treatment and controlled drying or lyophilization is applied. Lyophilization is an efficient and gentle method of drying ancient woods and leathers. Still, to assure freezing without damage to the pieces, they must be protected by a low-temperature agent, which is introduced in impregnation baths.
o Curative conservation: once in the conser- vation laboratory, the objects need to undergo a “curative conservation” procedure that com- prises several stages of cleaning of concretions, stabilization and rinsing. Cleaning the con- cretions and stabilizing the degradation, two closely interrelated procedures, help to render the object more comprehensible and allow for later risk-free restoration work. Most objects, especially if they have been buried in a seawater environment for many years, emerge covered by calcareous concretions. Their hardness, thickness and porosity depend on the characteristics of the sedimentary environment. That and the nature of the object itself will determine which cleaning, stabilizing and rinsing methods are most
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Conservation and site management