The Galle Maritime Archaeological Conservation Laboratory is the first and the main sophisticated lab in Sri Lanka for conserving underwater artefacts. The formal conservation process has been activated in this laboratory since 2001. The objectives were to train local conservators and to disseminate the knowledge of the process of maritime archaeological conservation in Sri Lanka. That program was conducted step by step since 1992 with the support of international and local cultural institutes. From 1992 to 2001, all conservators attended annual workshops in maritime archaeological conservation conducted by conservators from the Western Australian Maritime Museum. Several other local conservators had participated and trained in these annual workshops too. Dr. Ian Godfrey (Head of Material Conservation Department, Western Australian Museum), Jon Carpenter (Senior Conservator, Western Australian Museum) and some of their colleagues were trained local archaeological conservators since 1992.
The Avondster Project commenced in 2001; since then the conservators have been involved full time in the maritime archaeological conservation of various materials such as metals, wood, rope, ceramic etc. Foreign consultants with experience in marine archaeological conservation visit the project twice a year to assist the conservators with treatment problems. Also Central Cultural Fund consultants and the director of the laboratory visit and check the progress of the conservation work and the conservation requirements.
The dry conservation section – this consists of the chemical store, artefacts storage cupboards, fume cupboard etc. This area is use for conservation tasks such as preparing chemicals, cleaning of dry artefacts, the last stages of artefact treatment, documentation and conservation discussions.
The wet conservation area - This is the most important section where most of the conservation projects are in progress. This area is used to store artefacts during various treatments/ Clean artefacts using mechanical and chemical methods/ Register artefacts and to conduct collection management/ Demonstrate treatments and conduct training sessions.
The Documentation area – the room at the first part of the building is using as an administrative section and computer room. Most of the documentation work, conservation research work and records are stored in that room.
Apart from these, the premises of the MAU is also used for treating large artefacts such as anchors and cannons. There was also a chemical store, external storage area and large outside work area for working on large and dirty artefacts.
General Treatment Procedures for underwater Artefacts at the MAU :
Condition and Deterioration of underwater artefacts - Before starting conservation we have to gather all the information about the objects including factors which can cause deterioration in a wet environment such as: the nature of the artefact material, the nature of the surrounding materials, degree of oxygenation, temperature of the site, acidity or alkalinity of the burial environment, salinity, period of immersion, presence of bacteria, fungi and other organisms, extent of burial/exposure cycle, type of sediment and depth.
These factors can affect different material types in different ways. Some examples of deterioration of artefacts include:
- Loss or gain in weight
- Changes in size and shape
- Changes in colour
- Changes in chemical composition
- Loss of structural integrity
Treatment Considerations :
Before beginning the treatment of an artefact a conservator needs to consider and record the following factors: the history of the artefact, the material present, how the artefact is constructed, the condition of the artefacts, the principal of minimum intervention, and stabilization.
When objects are treated, it is essential to keep a detailed permanent record of the treatment. This record should include details of the condition of the objects before and after the treatment, a short description, and full details of the treatment carried out. We are maintaining both manual and computer databases for the treatment documentation.
Depending on the nature and condition of the object in question, materials are cleaned to remove soil and soft marine deposits by careful brushing. In many cases incorporated corrosion products are not only disfiguring but also chemically damage the objects. Before further treatment, these stains, concretions and deposits can be removed using chemicals and mechanical methods without damaging the artefacts. The fragility of wet textiles, including rope and matting, complicate their cleaning. These materials usually need to be supported on either glass/ Perspex sheets or netting when being cleaned.
All the artefacts from salt water/sea are usually desalinated,(remove salt by using fresh water) because once treated and dried, their high salt content could affect other artefacts kept near them. Composite artefacts usually require desalination in order to preserve both components.
In many cases, the objects are bulked by water, which takes the place of the degraded chemicalconstituents. This helps to maintain the shape of the object while it is in its wet state. Unfortunately, when drying takes place, shrinkage and warping result due to the loss of supporting structures and the collapse of cells. The aim of the consolidation treatmentis to prevent this damage by progressively replacing the water in organic objects with chemicals, which will support the residual structure.
Drying is a very important stage in the conservation of organic materials. Considerable stress is put on the artefacts by the movement of water molecules and changes in shape can occur if drying is not carried out correctly.