This is an ivory diptych, made in Paris in about 1300.
Ivory was used all over Europe for religious works of art. It was often combined with precious metals and usually took the form of relief panels, for book covers, portable altars and caskets. An almost unbroken tradition of ivory carving extends from the Roman and Byzantine empires until the end of the 14th century. From about 1250, Paris became the centre of production for figures and reliefs intended for private devotion.
The devotional diptych is in many ways the object type most associated with the notion of Gothic ivory carving. The earliest examples probably date to the 1240s; these are complex, large and ambitious works that emerged, somewhat surprisingly, with no obvious precursors. The owners of ivory diptychs sometimes appear within their images. Such portraits indicate that they were special requests on the part of their commissioners, and they parallel the similar figures that appear in manuscripts and panel paintings of the period. The iconography of Gothic diptychs oscillated between two poles. The first of which is the desire to present narratives (Life of Christ and Virgin Mary) for envisaging. The second was the use of non-narrative images to form the focus of devotion.