Dish with Sailing-ship Design - Public domain photo of museum object

İznik was an established centre for the production of simple earthenware pottery with an underglaze decoration when, in the last quarter of the 15th century, craftsmen in the town began to manufacture high quality pottery with a fritware body painted with cobalt blue under a colourless transparent lead glaze. The designs combined traditional Ottoman arabesque patterns with Chinese elements. The change was almost certainly a result of active intervention and patronage by the recently established Ottoman court in Istanbul who greatly valued Chinese blue-and-white porcelain. During the 16th century the decoration of the pottery gradually changed in style, becoming looser and more flowing. Additional colours were introduced. Initially turquoise was combined with the dark shade of cobalt blue and then the shades of piney green and pale purple were added. From the middle of the century the potters in Iznik produced large quantities of underglazed tiles to decorate the imperial buildings designed by the architect Mimar Sinan. Associated with the production of tiles was the introduction of a very characteristic bole red to replace the purple and a bright emerald green to replace the sage green. From the last decade of the century there was a marked deterioration in quality and although production continued during the 17th century the designs were poor. The last important building to be decorated with tiles from Iznik was the Sultan Ahmed Mosque (Blue Mosque) in Istanbul that was completed in 1616.