Citadel attributed to al-Mansur Qalawun

• The symmetry group of the tiling is 4*2 (p4g).
• All the internal angles of the constituent polygons are a multiple of 45°.
• Contains one square.
• There are three non-regular reflective tiles and one reflective pair.
• The tiling satisfies the two-colour condition.
• The tiling is not edge-to-edge.
• As drawn, contains about 387 polygons.

1. Page 20 (top) (Qalawun, Cairo, Egypt) of F M Hessemer. Historic Designs and Patterns in Color, Dover, a1840. ISBN 048626425. [hessemer] {This collection is unusual in giving the source for almost all the patterns.} Available on Internet.(1283-4AD, 681-2AH)
2. Page 74 (Zayn al-Din Yusuf, Cairo, Egypt. Entrance wall, black/white marble) of Bernard O'Kane. The Mosques of Egypt, AUC, Cairo, 2016. ISBN 978977416732. [okane2] {}(1298-1335AD, 697-735AH)

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