Iznik was the centre for the production of high grade frit ware. The best specimens are in several of the major museums of the world, many are in the Çinili Kösk on the ground of the Archaeology Museum in Istanbul. Or they are on the walls of the mosques built during the heyday of Ottoman reign, the mid-sixteenth century. The best in Istanbul are Sokollu Mehmet mosque and Rüstem Pasha Mosque, and in Edirne the Selimiye mosque. The Süleymaniye in Istanbul again is quite good also. The best book I know is “Iznik, The pottery of Ottoman Turkey” by Nurhan Atasoy and Julian Raby. You will find it in the better books shops in Istanbul, some museums and abroad. It costs an arm and a leg, but gives illustrations and in-depth treatment on almost any aspect of this great art.

This is a type of tile with "bulut" or cloud motives that were derived from China.

İznik town 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 tiles and pottery with a fritware body (frit being added to clay to reduce its fusion temperature), painted with cobalt blue under a colourless lead glaze. The meticulous designs combined traditional Ottoman arabesque patterns with Chinese elements. The change was a result of the 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 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 pastel shades of sage green and pale purple were added. Finally, in the middle of the 16th century, a very characteristic bole red replaced the purple and a bright emerald green replaced the sage green.

Correspondent: J.M.Criel, Antwerpen.
Source: Wikipedia .