A security document precursor including one or more lamellae provided with two or more holes near a perimeter edge surface of the precursor, wherein the holes perforate the largest surface of the one or more lamellae, and wherein at least one of the holes is filled with a colored material which differs in color from at least one of the one or more lamellae, such that the colored material is visible from a direction perpendicular on the perimeter edge surface; wherein at least one of the one or more lamellae is transparent or translucent: or wherein at least one of the one or more lamellae is opaque and the opaque part of the at least one of the one or more lamellae between the perimeter edge and the hole filled with a colored material has been removed. A security document and a method of preparing the security document precursor are also disclosed.