Kissing Rings, Bracelets, Roses and Canadian Magnetic Coins: Circle Packing with Ferrite Block Magnets and Magnetic Sheet

Maria Victoria Canullo, Veronika Irvine and Robin Linhope Willson
Proceedings of Bridges 2017: Mathematics, Art, Music, Architecture, Education, Culture
Pages 253–260 Regular Papers


The Royal Canadian Mint has a long history of producing high quality coins made of pure nickel or plated steel. As such, the coins are ferromagnetic enabling them to be fixed to a surface, or suspended or stacked on their rims via magnetism. The background to such use was described at the 2015 Bridges Baltimore Conference. Here we provide further artistic examples of near-close-packed coin arrays constructed using safe ferrite block magnets or magnetic sheet. In many cases only coins of Canada are present. Where Canadian coins of a suitable diameter are unavailable, coins of the UK, the European Union, Argentina, Brazil or Uruguay are included. The emphasis of this paper is on the geometry of bracelets and roses, formed from two or more connected rings, and how well we can approximate a perfect close-packing given the restricted diameters of the found objects, coins, used in our art.