X-rays allow conservators to look underneath the surface of an object without damaging the object itself.
Excavated iron, with an x-ray showing a buckle inside. Accession number 1981.895
For example, this excavated iron above just looks like a lump of material. It is not even obvious that there is something inside it. Analysis using x-ray radiation showed that there are the remains of a harness buckle inside. In fact the actual harness has rusted away. All that remains are the traces of the corroded metal in the shape of the original object. The buckle was probably used on an animal harness.
Pattern welded Anglo Saxon sword, with an x-ray showing the pattern. Accession number Sw.U.5
X-ray analysis of these two pieces show that they are are both part of an Anglo Saxon sword. The sword has been made using a technique called pattern welding. Pattern welding is what can be seen in the 'herring bone' patterns visible on the x-ray image.