Seal of Muhammad

The Seal of Muhammad (Turkish Mühr-ü Saadet or Mühr-ü Şerif; Arabic ختم الرسول) is one of the relics of Muhammad kept in the Topkapı Palace by the Ottoman Sultans as part of the Sacred Relics collection. It is allegedly the replica of a seal used by Muhammad on several letters sent to foreign dignitaries.

Jean-Baptiste Tavernier in 1675 reported that the seal was kept in a small ebony box in a niche cut in the wall by the foot of a divan in the relic room at Topkapi. The seal itself is encased in crystal, approximately 3"x4", with a border of ivory. It has been used as recently as the 17th century to stamp documents.

The seal is a rectangular piece of red agate, about 1 cm in length, inscribed with الله / محمد رسول (i.e. Allah "God" in the first line, and Muḥammad rasūl "Muhammad, messenger" in the second). According to Muslim historiographical tradition, Muhammad's original seal was inherited by Abu Bakr, Umar, and Uthman, but lost by Uthman in a well in Medina. Uthman is said to have made a replica of the seal, and this seal was supposedly found in the capture of Baghdad (1534) and brought to Istanbul.

A different design of the "seal of Muhammad" is circular, based on Ottoman era manuscript copies of the letters of Muhammad. This is the variant that has become familiar as the "seal of Muhammad" in jihadism, used in jihadist flags since ca. 2006, notably by the Islamic State of Iraq and the Levant/Daesh and by its sympathisers; some jewelry manufacturers have offered actual signet rings in this design long before the seal gained infamy through terrorist organisations.

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Wikipedia