This multipurpose structure began as an 8th-century oratory and then in 1290 was turned into an open-air loggia for selling grain. Destroyed by fire in 1304, it was rebuilt as a loggia-market. Between 1367 and 1380 the arcades were closed and two stories were added above; finally, at century's end it was turned into a church. Inside is a beautifully detailed 14th-century Gothic tabernacle by Andrea Orcagna (1308–68). The exterior niches contain sculptures (all copies) dating from the early 1400s to the early 1600s by Donatello and Verrocchio (1435–88), among others, which were paid for by the guilds. Although it is a copy, Verrocchio's Doubting Thomas (circa 1470) is particularly deserving of attention. Here you see Christ, like the building's other figures, entirely framed within the niche, and St. Thomas standing on its bottom ledge, with his right foot outside the niche frame. This one detail, the positioning of a single foot, brings the whole composition to life. It's possible to see the original sculptures at the Museo di Orsanmichele, which is open Monday only.