Packaging aid having integral guarantee of original pack and/or first-time opening containing a substrate with a surface that reflects visible light. The reflective surface is made of metal or is a metallic reflective surface. One or more single ceramic layers are provided on the reflecting surface. The ceramic layers are made of a compound having the formula SiOx, where x represents a number from 1.5 to 2.0, each ceramic layer has a thickness of 50 to 2000 nm. The ceramic layer is directly, nonreleasably affixed to the substrate or to the reflective surface of the substrate. On the ceramic layers, a reflecting layer which is semipermeable to visible light is provided. The reflective layer is made of metal and has a thickness of 0.2 to 60 nm, and is such that light striking the coated substrate is reflected and seen as different colors depending on the direction or angle at which it is viewed by an observer.