Lustreware or Lusterware is a type of pottery or porcelain with a metallic glaze that gives the effect of iridescence. It is produced by metallic oxides in an overglaze finish, which is given a second firing at a lower temperature in a "muffle kiln", or a reduction kiln, excluding oxygen.
The technique of lustreware on pottery was first developed in Mesopotamia in the early 9th century. Initially mostly decorated with geometric patterns, by the 10th century an Iraqi style with the design dominated by one or two large figures developed. After the Fatimid conquest of Egypt in 969, it became a great centre of lustreware production until the Fatimid Caliphate fell in 1171, soon after the potter's quarter of the capital Fustat was burned in 1169. It is thought that the Fustat potters dispersed to both Syria and Persia, and lustreware appears there about this time; later the devastating conquests of the Mongols and Timur disrupted these industries. The technique had spread to al-Andalus. Hispano-Moresque ware in lustre was mostly produced in Christian Spain, especially in the region of Valencia, and later Barcelona.