This large, two-handled drug jar has an exceptionally rare shape and bold design. It was produced for the pharmacy of the Sienese hospital of Santa Maria della Scala, whose emblem-a three-runged ladder ( scala a pioli ) surmounted by a cross-appears on both sides. This emblem refers to the hospital's location in front of the steps ( scale ) of the city's cathedral. The emblem is framed on one side by two birds, possibly peacocks, and on the other by two human-faced birds, or harpies, who were monsters believed to torment misers in the fifteenth century. The surface is also decorated with stylized leaves and dots, which resemble oak leaves and berries.
The decoration is painted in a very thick, cobalt-blue impasto, often called relief blue because it was applied so thickly that it seems to stand out from the vessel's surface. The leafy shapes are outlined in, and scattered with, touches of manganese purple. Under each handle is a letter P , possibly intertwined with a backward C, which may be the mark of the Florentine workshop of Piero di Mazeo.