Statement on Conservation

Conservation of Sigillographic Collections by Agnès Prévost, Département de la conservation, Archives nationales, Paris

Seal matrix with attachment chain.
Seal impression with a cord.
Sulphur cast from a seal impression.


Seals are preserved in archives, museums, libraries but also in private collections. But what are these ‘seals’, which we wish to conserve? Confusion is caused by the various categories of sigillographic objects:

  • the seal matrix: metallic object to impress a seal;
  • the seal itself: a three-dimensional object of one or more matrices in wax or [soft] metal;
  • the seal cast: made of plaster, sulphur or resin in order to reproduce a matrix or an original impression.

This variety of objects raises the issue of collecting even when writing on conservation. All sigillographic objects have a particular value, which demands their best possible care. From the conservator’s perspective it is essential to categorize these objects’ properties in order to determine the proper mode of their conservation. Effectively, each object bears witness to specific alterations, a variable sensitivity against its environment and necessities concerning interventions and conditions of conservation.

The prevention of risks is the most important approach towards the conservation of collections as it makes interventions unnecessary. If restoration is unavoidable it is absolutely necessary to call for specialists. As restorations are always severe interventions, the conservator’s main priority is to consolidate the object without too much alteration.

Typology of sealed documents

Conditions of conservation of sigillographic material