Colour symmetry. Portuguese pavements: Lisboa, Praça do Município, Eduardo Nery - p4mm - «p4mm»

Versão da minha exclusiva responsabilidade, feita para este blogue, de uma parte (expandida no desenho) do pavimento da Praça do Município, de Lisboa, cujo autor é Eduardo Nery. Esta versão destina-se apenas a mostrar as propriedades geométricas dessa parte do pavimento.

Numbers mean rotations of order 2 and 4. Mirrors are represented by red lines. Glide reflections are not represented.
p4mm

Colour symmetry in the same pattern. Small circles mean rotations; numbers mean rotations of order 2 and 4. Mirrors are represented by red lines. Glide reflections are not represented. (12) means that the colours white and grey are interchanged; i means the identity.

This is an example of the case stated in the fourth row of the table in Section 4.10 (Figure 14, «p4mm») in

Periodical plane puzzles with numbers

Eduardo Nery

Image scanned from the book

Eduardo Nery. Exposição Retrospectiva: Tapeçaria, Azulejo, Mosaico, Vitral (1961-2003)

See:

Wallpaper groups. Portuguese pavements: Lisboa, Praça do Município, Eduardo Nery - p4mm

Portuguese pavements: Eduardo Nery, Praça do Município, Lisboa, Portugal

Museu Nacional do Azulejo - Eduardo Nery

Eduardo Nery (Official Website)

Eduardo Nery (in this blog)