Decorative, geometric architectural pattern cut from stone or made of bricks, used to fill the upper part of the gothic windows, open-works, rosettes, etc. It also appears as a decoration of walls, gables and blendes. Then it is called a blind tracery. The first tracery appeared in the chapels of the Notre Dame cathedral in Reims around 1230. With time the tracery became more and more openwork, and the geometric elements used in them became increasingly complex. Initially it was a combination of wheels, hexagons, pointed bends. In the mature and late gothic, the motif of the fish bladder and the four and tri leafs were used.