An official lead seal (bulla), single-sided, struck during the turbulent transition period of the Abbasid Revolution against the Umayyad Caliphate. In the margin (Kufic script): "Order of Abdullah, Commander of the Faithful, in the year one hundred and thirty-one" (Amr Abdullah Amir al-Mu'minin sanat ihda wa thalathin wa mi'ah). In the center: "Seal... twenty-four" (Khatam... arba'a wa 'ishrin). Historical Context: While traditionally linked to the very end of the Umayyad period due to the date (131 AH / 748-749 CE), the inscription explicitly names "Abdullah, Commander of the Faithful". This refers to the early Abbasid authority (likely Abu al-Abbas al-Saffah, born Abdullah), whose forces were already issuing administrative and fiscal seals in the eastern provinces during the height of the Abbasid Revolt, just one year before the final collapse of the Umayyad dynasty in 132 AH. This makes the piece an exceptional and highly important historical document of political transition. Condition: Fine / Good Fine. Well-preserved perimeter with a clear, readable marginal inscription. Central fields show typical wear and flattening due to historical usage. Stable, authentic light-grey and whitish carbonate patina. Weight: 35.46 g. Dimensions: 3.5 cm x 3.0 cm. Provenance: Acquired in 2025 from Demeter Coins (Falk Zünkler), Germany. Formerly part of a private collection in Spain, originally acquired in 1987 from a local antiquities dealer. Accompanied by the original purchase invoice and a certificate of authenticity.