From Silchester and Hadrian's Villa at Tivoli. Also as a window grill in Salisbury Cathedral, see, Field page 35, but in different proportions.

This pattern is a member of an interesting class of mathematical patterns. PP Class 59, [p4,c4,c1], IH Class 28.

Statistics on this tiling:

- Tiling has symmetry
*p4*. - Tiling has 2 polygons and 10 edges.
- Edges are completely connected.
- Tiling is not edge-to-edge.
- Tiling satisfies the two-polygon condition.
- Internal angles a multiple of 90°.
- Contains one non-regular polygon which has reflective symmetry.
- Contains: one square.
- Tiling contains 226 polygons.