Kevkeb-i Dürri Diamond and Sultan Ahmed's Secret Inscription

Kevkeb-i Dürri (كَوْكَبٌ دُرِّيٌّ — Bright Star) is the name used to describe a diamond that is said to be an extremely rare jewel located in the Ottoman treasury. This name is also a term mentioned in the 35th verse of Surah An-Nur: "...Allah is the Light of the heavens and the earth. The example of His light is like a niche in which there is a lamp; the lamp is in glass; the glass is as if it were a shining star (kevkebun durriyyun)..." Sultan Ahmed I (1590-1617) was an extremely devout sultan. It is known that he had a deep attachment to Mecca and Medina; like many Ottoman sultans, he left valuable gifts and foundations for these holy places. According to the explanation by Adnan Şensoy, Sultan Ahmed has a secret inscription left in the Prophet's Mosque or a related structure. This inscription is considered a permanent expression of the sultan's faith and a prayer or supplication he wished to keep hidden from ordinary eyes. During the final period of World War I, the Governor of Medina, Fahrettin Pasha (Turkmen), defended Medina as the last garrison of the Ottomans, who resisted the British-Arab forces for a long time. When he had to surrender (1919), he sent the valuable artifacts and jewels from the Prophet's Mosque to Istanbul. It is reported that among these treasures was the Kevkeb-i Dürri Diamond. [Source: TDV Islamic Encyclopedia, "Fahreddin Pasha" article, islamansiklopedisi.org.tr/fahreddin-pasa; Ottoman period Hijaz sources]