The high resolution, high contrast nature of CT imaging is ideal for the assessment of the internal structure of artefacts. Where conventional x-rays can only produce a 2D image, the sequential ‘slices’ through an item with CT, produce an internal 3D reconstruction.
CT is extremely useful for identifying the inner density of materials which can help to reveal the extent of restoration of artefacts.
Unexpected differing densities of materials, internal rods and glue lines together with expert knowledge of the piece in question can all be used to suggest a forgery or fake.
Sometimes real materials from the period in question are placed on the surface of an item, to fool experts and laboratory tests such as thermoluminescence (TL) – with more modern materials used internally which are hidden to the naked eye. These internal differing densities can be detected on a CT scan helping identify forgeries or fakes.
The high resolution nature of CT can help identify tiny cracks, repair lines and inner wear.