The material used to make this jar is known in Italy as maiolica. It is earthenware with a thick, opaque white surface called tin glaze. Maiolica was one of the first ceramics to be used specifically as a vehicle for painted decoration, either in lustre or in painted enamels.As a branch of pottery manufacture, maiolica was established in the northern half of Italy by the mid-15th century when the pots were often decorated with bold patterns in green and purple. As the industry developed throughout Italy, characteristic shapes emerged, amongst them jars like this used for storage.This jar has a very bold pattern painted in manganese purple and copper green. It is an unusually large and fine survival of this early type of maiolica.