Mosaic from Silchester and Hadrian's Villa at Tivoli.

• The symmetry group of the tiling is 442 (p4).
• All the internal angles of the constituent polygons are a multiple of 90°.
• Contains one square.
• There is one non-regular reflective tile.
• The tiling does not satisfy the two-colour condition.
• The tiling is not edge-to-edge.
• The tiling satisfies the two-polygon condition.
• As drawn, contains about 153 polygons.

• PP Class 59, [p4,c4,c1], IH Class 28 from [dawes]
• Page 16 (Also as a window grill in Salisbury Cathedral) from [field1]
• Page 35 from [field2]

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