Fritware, also known as stone-paste, is a type of pottery in which frit (ground glass) is added to clay to reduce its fusion temperature. The mixture may include quartz or other siliceous material. An organic compound such as gum or glue may be added for binding. The resulting mixture can be fired at a lower temperature than clay alone. A glaze is then applied on the surface. Fritware was invented to give a strong white body, which, combined with tin-glazing of the surface, allowed it to approximate the result of Chinese porcelain. Porcelain was not manufactured in the Islamic world until modern times, and most fine Islamic pottery was made of fritware. Frit was also a significant component in some early European porcelains. A small manufacturing cluster of fritware exists around Jaipur, Rajasthan in India, where it is known as 'Blue Pottery' due its most popular glaze. The Blue Pottery of Jaipur technique may have arrived in India with the Mughals, with production in Jaipur dating to at least as early as the 17th century. Composition and techniques Fritware was invented in the Medieval Islamic world to give a strong white body, which, combined with tin-glazing of the surface, allowed it to approximate the white colour, translucency, and thin walls of Chinese porcelain. True porcelain was not manufactured in the Islamic world until modern times, and most fine Islamic pottery was made of fritware. Frit was also a significant component in some early European porcelains. Although its production centres may have shifted with time and imperial power, fritware remained in continued use throughout the Islamic world with little significant innovation. The technique was used to create many other significant artistic traditions such as lustreware, Raqqa ware, and Iznik pottery. Raw materials in one contemporary recipe used in Jaipur are quartz powder, glass power, Fuller's earth, borax and Tragacanth gum. Raw materials for a glaze are reported to be glass powder, lead oxide, borax, potassium nitrate, zinc oxide and boric acid. The blue decoration is cobalt oxide. History Frit is crushed glass that is used in ceramics. The pottery produced from the manufacture of frit is often called 'fritware' but has also been referred to as "stonepaste" and "faience" among other names. Fritware was innovative because the glaze and the body of the ceramic piece were made of nearly the same materials allowing them to fuse better and less likely to