Yaqut al-Musta'simi (Arabic: ياقوت المستعصمي) (died 1298[1]) was a well-known calligrapher[2][3] and secretary of the last Abbasid caliph.

[5] He studied with the female scholar and calligrapher, Shuhda Bint Al-‘Ibari, who was herself a student in the direct line of Ibn al-Bawwab.

[6] During the Mongol invasion of Baghdad (1258), he took refuge in the minaret of a mosque so he could finish his calligraphy practice, while the city was being ransacked.

[9] He developed Yakuti, a handwriting named after him, described as a thuluth of "a particularly elegant and beautiful type.

Although, he is said to have copied the Qur'an more than a thousand times,[12] problems with attributing his work, may have contributed to exaggerated estimates.