Guilloche
A graphic element in the form of a complex geometrical pattern which consist of repeated thin curved lines formed according to certain mathematical rules. Guilloche elements form rosettes, frames, borders, vignettes and elements of a background pattern. Guilloche elements can be both positive and negative.
![Russian Federation. Diplomatic passport issued in 1995: front endpaper. Paper substrate](https://static-content.regulaforensics.com/Hardware-products/knowledge_hub/glossary_documents/GUILLOCHE/1l.webp)
a
![Russian Federation. Diplomatic passport issued in 1995: the same. Negative (light-coloured, non-printed lines on the dark background) and positive (dark lines on the light-coloured background) guilloche. Intaglio printing](https://static-content.regulaforensics.com/Hardware-products/knowledge_hub/glossary_documents/GUILLOCHE/2l.webp)
b
Fig. 1. Russian Federation. Diplomatic passport issued in 1995:a — front endpaper. Paper substrate; b — the same. Negative (light-coloured, non-printed lines on the dark background) and positive (dark lines on the light-coloured background) guilloche. Intaglio printing
![The Czech Republic. Diplomatic passport issued in 2005: page 17. Fragment of the background pattern formed by guilloche elements. Paper substrate](https://static-content.regulaforensics.com/Hardware-products/knowledge_hub/glossary_documents/GUILLOCHE/3l.webp)
a
![The Czech Republic. Diplomatic passport issued in 2005: the same. Zoomed fragment. Guilloche. Offset printing](https://static-content.regulaforensics.com/Hardware-products/knowledge_hub/glossary_documents/GUILLOCHE/4l.webp)
b
![The Czech Republic. Diplomatic passport issued in 2005: the same. Front endpaper. Vignette](https://static-content.regulaforensics.com/Hardware-products/knowledge_hub/glossary_documents/GUILLOCHE/5l.webp)
c
![The Czech Republic. Diplomatic passport issued in 2005: the same. Zoomed fragment. Vignette. Intaglio printing](https://static-content.regulaforensics.com/Hardware-products/knowledge_hub/glossary_documents/GUILLOCHE/6l.webp)
d
Fig. 2. The Czech Republic. Diplomatic passport issued in 2005:
a — page 17. Fragment of the background pattern formed by guilloche elements. Paper substrate; b — the same. Zoomed fragment. Guilloche. Offset printing; c — the same. Front endpaper. Vignette; d — the same. Zoomed fragment. Vignette. Intaglio printing