Cuerda seca

In the cuerda seca technique, the water-soluble glazes are separated on the surface by thin lines of a greasy substance to prevent them running out of their delineated areas.

Many scholars believe that the cuerda seca technique originated primarily in al-Andalus (Islamic Spain and Portugal) in the second half of the 10th century, during the Umayyad period (citing Umayyad-era examples from Suza).

[2][3][4][5] Scholar Juan Zozaya argues that the advent of this style in al-Andalus could have been spurred by Chinese ceramics which were imported to the region from an early period.

[3] Preserved fragments of tiles from the late 12th-century minaret of the Kasbah Mosque in Marrakesh, Morocco, have been cited as the earliest surviving example of cuerda seca tilework being used for architectural decoration.

In the 1360s the colours were restricted to white, turquoise and cobalt blue but by 1386 the palette had been expanded to include yellow, light-green and unglazed red.