Welcome to the Glamorgan-Gwent Archaeological Trust (GGAT) conservation webpage and blog. Over the next several weeks I, and others, will be posting on the conservation cleaning and treatment of a variety of archaeological materials recovered from excavations at Cardiff Castle. The goal of these posts is to inform on the conservation of some of the materials excavated from the grounds of Cardiff Castle. With each post we will look at the conservation of selected artefacts or use of a specific conservation or analytical technique. Look for periodic conservation posts to have a peek at what we, as conservators, are doing to conserve artefacts and to expand on the story of Cardiff Castle and Cardiff as a city.
As background, GGAT contacted Cardiff Conservation Services at Cardiff University to work on a selection of artefacts excavated from the footprint of the current Interpretation Center within the walls of Cardiff Castle. The objects, most of which are Roman in origin, are varied and consist of iron, copper alloy, silver, stone and glass.
Most of the archaeologically recovered material consists of metal objects. This material is typically covered in corrosion and soil from the burial matrix. The corrosion and soil may require removal to expose the original surface details and reveal additional information, such as presence of decoration. Some objects may be broken and require re-adhering. Other objects could be actively corroding. Most objects will exhibit a combination of these conditions and possibly some conditions not yet mentioned. Other material types will present their own issues and will be covered in upcoming posts.
The conservation goal for the Cardiff Castle objects is stabilization in preparation for long-term storage. Stabilization of the objects will facilitate their preservation and allow future study and/or display of them. A secondary goal is to reveal additional information such as how were they constructed and the presence/absence of decoration.
Various techniques were used during the conservation of these objects. Photographs were taken before and after, and in many cases, during conservation. X-Radiography was used to identify heavily encrusted objects and to determine if further conservation is warranted. Cleaning using bench tools, and possibly chemicals, was required to reveal the original surface and additional information. X-Ray fluorescence and scanning electron microscopy was used to provide elemental composition which, in turn, provided additional information on technology.
We will post at intervals of at least once every two weeks but posts will be made more frequently at times. Join us for our next conservation post as we report on the X-radiography of corrosion-encrusted iron objects.