Conceptual design of the collector coins "Innovations of Slavoljub Penkala"
The basic motif of the conceptual design features Slavoljub Eduard Penkala, one of the most significant Croatian innovators, whose surname Penkala has become synonymous with ballpoint pens in the Croatian language. His greatest and most famous invention, among many others, is the automatic mechanical pencil, known as "penkala" in Croatian, one of the inventions by Croatian innovators still widely used today, which puts Penkala’s work on the list of cultural and scientific heritage of the Republic of Croatia and the world. The author is Illaria Longo.