It is called a tughra. … This tughra has been drawn on heavy paper in bold lines of blue cobalt ink, enclosing what looks like a tiny meadow of colourful, golden flowers. … It’s an elegant, elaborate monogram cut from the top of an official document, and the whole design spells the title of the sultan whose authority it represents.

Neil MacGregor, A History of the World in 1…, loc. 1101