Pisanello, ‘Cecilia Gonzaga, 1426-1451, daughter of Gianfrancesco I [obverse]’, 1447, National Gallery of Art, Washington, D.C.
overall (diameter): 8.66 cm (3 7/16 in.)  gross weight: 215.56 gr (0.475 lb.)  axis: 12:00

About Pisanello