Giovanni di Bartolomeo Christiani
Madonna and child enthroned with attendant angels. 1365-1370

Initially this was the central part of a polyptych: the side panels with depictions of saints are in the Hermitage Museum (St. Romuald and St. Andrew) and in the Bandini Museum in Fiesole.

About restoration
Go to the full description on "Italian painting in VIII-XX centuries" catalogue.