The preservation of geological collections

Amgueddfa Cymru is one of the few museums in Europe with expertise in geological conservation, and has been active in training and advising conservators in other museums. The discipline of geological conservation is relatively new. Geological material may appear to be strong and durable; but there are many factors that can lead to the deterioration, even the complete destruction of fossils, minerals and rocks. Environmental factors, including incorrect temperature and humidity, light and pollution are the main threats, but damage can also be caused by poor storage and packaging.

Many rocks, fossils and minerals are sensitive to relative humidity (RH) and can be damaged or destroyed if stored in an inappropriate environment. High RH can be a major problem for geological material because it can initiate oxidation reactions such as pyrite decay (sulphide oxidation), deliquescence, and the deformation of some material through the absorption of moisture. It can also encourage moulds and some insect pests, which can destroy labels and other documentation. Very low RH can cause the efflorescence of some minerals and shrinkage of moisture absorbent specimens such as shale and sub-fossil bone.

Two research projects are currently being undertaken to examine why and how some geological material deteriorates. This will help us to better preserve our collections for the future.