The Thomson Collection contains examples of the highest quality of most types of medieval ivory carving, both secular and religious. These include large statuettes of the Virgin and Child intended to stand on altars in chapels, small versions for private use in the home and folding tablets or diptychs with scenes from the life of Christ carved in relief. Alongside these are beautiful small carved writing tablets, boxes and caskets, combs, hair parters, mirror cases with scenes of romantic encounters between elegant young men and women, and a rare set of carving and serving knives with fabulous beasts decorating the ivory handles.

The magnificent Dormeuil Diptych of the Passion of Christ is a highlight of the collection and appears to be the largest ivory Passion diptych extant. Equally remarkable is a controversial Nativity and Last Judgment diptych which had been considered 'too good to be medieval' and dismissed as a forgery, but has now been carbon-14 dated to the late 12th or early 13th century. Other significant medieval works include examples of stained glass, woodwork and metalwork, notably the 12th-century Malmesbury reliquary casket.