St. John the Evangelist sits in the foreground with a book open on his knee and quill pen poised over its pages. Two books rest next to him and an eagle has alighted on an adjacent rock. St. John looks up and to his right to see a standing figure of the Virgin Mary holding the infant Christ, who appear in a glowing mandorla hovering in the sky. A vast panoramic view of a bustling harbor and formidable mountains unfolds behind St. John and extends into the distance.
This cup is fashioned from a coconut shell set in a shallow bowl supported on a long, narrow stem and held in place by three straps and a tall neck band. The shallow domed lid has a plain, overhanging rim and terminates in a finial with a statuette of a nude sea nymph and serpent. The metalwork is densely decorated with various masks, animals, fantastic creatures, and vegetal ornament.