Solid gold

"Plein-or" is the term used in bookbinding to describe large tools pressed onto the covers of books in a single stamping motion to create a complete design.

Plein-or binding is characteristic of the great 17th-century bookbinders. It is very rare and highly sought after. These plein-or bindings are designed with small tools and are often filigreed. Plein-or binding was sometimes copied by great 19th-century binders.

^{Contribution Bertrand Galimard Flavigny}