King Solomon and the Queen of Sheba' by Konrad Witz, 1435. In this panel from the Heilspiegel Altarpiece, Witz painted a gold background with filigree ornamentation and placed both his figures before it. The blue, red, green, and white of the clothing and the restrained ochre of the hands and faces may be the only colours, but they radiate light when set against the intense gold of the background, whose effect is increased still further by the elaborate inlay pattern. Witz recognized that an abstract gold background sharpened the contours of a form and made it almost tangible. From the collection of the Staatliche Museen, Berlin, Germany.