Sundial-compass with Madonna Hodegetria

Diptych of two bone plates that can be opened. The exterior is decorated with a relief of the Madonna Hodegetria (‘She who shows the Way’), which has been blackened. One side of the interior shows an engraved compass rose of three concentric circles with arrows indicating the points of the compass and hour markings in Roman numerals, surrounding a recessed round field that contained the compass needle. In the four corners of this bone plate, quarter-circles with sunbeams and a small rosette have been applied. The other side contains a rosette of two concentric circles with hour numerals and hour lines, for the sundial, whose ‘gnomon’ is formed by the (now missing) cord between both plates. The engraved depictions on both plates are pigmented in green and red. An iron catch is located on the top of the pocket compass. The Rijksmuseum, Amsterdam, holds this object as BK-2024-31; its record gives material recorded as iron (metal), pigment, bone (material); technique cutting; measurements height 9.1 cm x width 7.3 cm x depth 0 cm. Description translated from the museum's Dutch catalogue text; details are those of this museum object, and how far it represents a wider type has not been independently verified.