Problems of dating
the published wares from Samarra were traditionally thought to be dated specifically within the period of Caliphal occupation at Samarra from 836-882.However, the mint at Samarra was known to be functioning in 833, before the Caliph al-Mutasim even moved there, and occupation at the site is still attested in the mid tenth-century by the writers Ibn Hawqal and al-Muqaddasi who both went there, giving a period of occupation of at least 150 years.The unreliability of the dating of the Samarra horizon evidence thus argues for a low (ie. One fixed piece of dating evidence is provided by the reconstruction of the mihrab of the Qairawan mosque, in present-day Tunisia.
Adams is another advocate of a high (ie.
earlier) chronology by his assertion that the evidence at Tell Abu Sarifa shows a Sasanian derivation for the emergence of an Islamic white glazed pottery, while other scholars have suggested the technique comes from the Romans via the Umayyads.
Another problem which has effected the understanding of the ceramic chronology is the so-called Samarra horizon: ie.
These tiles still survive around the mihrab, and are decorated in polychrome and bichrome lustre techniques but there is no use of monochrome, which Hallett thinks only becomes the dominant technique on lustre at the very end of the ninth-century.
We can therefore say with certainty that a fully-developed polychrome palette had been achieved by the time the tiles were sent to Qairawan in the mid-ninth-century.