a practice that became especially marked during the long and prosperous reign of Ahmad al-Mansur. Al-Mansur's increased relations with the Ottoman Empire, particularly during the reign of Mehmed III (1595–1603), resulted in numerous embassies to the Ottoman court which exchanged gifts, including richly-produced Qur'an manuscripts. Older manuscripts produced in Al-Andalus were seen as especially dignified gifts and many such examples in the library of Topkapi Palace today may have come from Saadian embassies. In return, the Saadian libraries acquired an even larger number of Ottoman or Middle Eastern manuscripts, some of which remain in Moroccan royal libraries today. Another major and important collection of royal manuscripts, the Zaydani Library, was taken from Sultan Moulay Zaydan by the Spanish in 1612 and has been kept in the library of El Escorial up to the present day. Among other volumes, it contains a richly-produced royal Qur'an dated to 1599, commissioned by Ahmad al-Mansur but known as the Qur'an of Moulay Zaydan (or Koran de Muley Zaidan in Spanish). Another richly-decorated royal Qur'an, written for Sultan Abdallah al-Ghalib and dated to 1568, is kept by the British Library. Although the script was written generally in black ink, various orthographic signs (such as vowels and diacritics) were written in red, blue, or orange. Chapter headings were in gold Kufic (a practice widely used in illuminated Qur'an), with the empty spaces between or within letters filled with blue. This multi-colouring practice is widely found in historic Qur'an copies from this region and traces its origins to Abbasid manuscripts. Blue and gold ornamentation, consisting of specific shapes filled with arabesque motifs, is also painted in the margins to mark other divisions in the text: ornate palmettes marked chapter divisions, roundels marked every ten verses, and teardrop shapes marked every five verses. The beginning and end of the manuscript are decorated with illuminated interlacing motifs similar to that seen in some Andalusi examples centuries earlier. The increased cultural contacts with the Ottoman Empire are also apparent in the experimentation of Maghrebi authors with eastern traditions of manuscript production and calligraphy. For example, the use of thuluth, an eastern script adapted into a regional variation known as Maghrebi thuluth, was used in Marinid and Nasrid art (13th-15th centuries) or even earlier. However, in the late 16th century it became more systematized in manuscripts, often used for important words or for illuminated titles. Additionally, the repertoire of decorative motifs