Plate 11 shows Salvador Dalí’s Slave Market with Invisible Bust of Voltaire. We learn much about the surfaces and source(s) of light in this scene from the reflections he painted in the composition. The red cloth in the foreground has a sheen. The two vessels on top of the cloth are made of different materials—the one on the left (possibly a candle-holder or stand for the bust depending on which view registers in the visual system) appears to be made of metal with a matte finish, possibly bronze. The dish on the right of the table is made of unglazed ceramic or unpolished metal. The sand on the far-right of the picture reflects light uniformly while the leg of the person nearby is shinier indicating an oily skin. Light for the scene appears to come from a large and distant source on the top left, possibly the sun. We infer this location partly because shadows are long and appear on the right side of objects.