Potters during the early Islamic era continued to use many of the techniques that had existed long before. In Mesopotamia, there was a re-discovery of the ancient technique of combining tin oxide with a clear lead glaze. When applied to an earthenware body, the results came pleasingly close to the look of porcelain. Another advance in 9th century Mesopotamia was the development of lustreware, a shimmering metallic effect which went through a number of revivals in other regions. From the decorative viewpoint, the most striking achievement of this formative era was the addition of Arabic calligraphy. Entirely Islamic in spirit, this simple device turned ceramic vessels into elegant declarations of faith.
The inventiveness of Muslim potters was unrelenting. Calligraphic inscriptions were used to enormous effect in a number of different techniques. There is a long aesthetic leap from the monochrome precision of 10th-11th century Nishapur to the textured, turquoise-glazed wares that developed in Iran over the following centuries. Technical innovations allowed for new body types, many of which depended on the composite material known as ‘frit’. The pursuit of ever more colourful products led to the introduction of overglaze painting such as Minai wares. By this stage, ceramics had become as much an art of the painter as the potter.
Lustreware continued to reassert itself in the 13th century, with densely decorated calligraphic tiles being a speciality of Kashan. While bowls and dishes comprise the bulk of earlier ceramics, tiles became increasingly significant after the Central Asian migrations of the 12th century. Chinese influence also became more apparent. Instead of being inspired by shapes from the Far East, Muslim potters took a closer look at the motifs. A magnificent hybrid art emerged, still uniquely Islamic with its prominent use of Arabic and Persian calligraphy.
The emphasis was very different in the Ottoman Empire, whose contribution will be remembered mainly for Iznik ceramics. These relied little on calligraphy and a lot on bold floral designs. After the early blue-and-white decoration of the 15th century, the next two hundred years saw the arrival of flowers and other motifs in vivid colours, painted with a liberated hand. Tiles were once again an important feature, with buildings throughout the empire decorated in stunning patterns created from tiles that were either repeats or formed part of a larger pattern. After the decline of Iznik in the 17th century, it was Iran that maintained the Islamic world’s superiority in the production of ceramics.