A fantastic large size turquoise-glazed bowl of an inverted cone shape, straight plain rim, short cylindrical foot and an unglazed exterior. The bowl was probably made in Kashan or Nishapur, Iran.
Kashan was a Persian city known for producing high-quality pottery during the medieval period, at least form the 12th century and up to the 14th century CE. The town was well-located, near sources of minerals needed to create their distinctive stonepaste, also known as fritware, namely an artificial ceramic body made from ground quartz with small additions of clay and ground glaze-mixture.
The bright turquoise colour of this bowl is due to the use of copper oxide as a colourant.