Bourgoin, Plate 123

• The symmetry group of the tiling is *632 (p6m).
• All the internal angles of the constituent polygons are a multiple of 1.25°.
• Contains one regular 9-pointed star polygon with vertex angle of 72.5°.
• Contains one regular 12-pointed star polygon with vertex angle of 72.5°.
• There are 16 non-regular reflective tiles (including 5 kites).
• The tiling satisfies the interlace condition and has three finite interlaces and no infinite interlace with straight cross-overs.
• The tiling is edge-to-edge.
• As drawn, contains about 955 polygons.

1. vol 2, page 255, Figure 252 (Imam Yahya, Mosul, Iraq) of Friedrich Sarre and Ernst Herzfeld. Archäologische reise im Euphrat..., Berlin, 1911-20. ISBN . [sarre] {}(1239AD, 636AH)
2. Page 123 of J Bourgoin. Arabic Geometrical Pattern and Design, Dover, 1879. ISBN 048622924. [bourgoin] {Classical book of around 200 hand-produced patterns, in back and white.} Fuller version available on Internet.

• Wade photo BOU 123

• Tilings not constructible by straightedge and compass

Photo?

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