The template for the IH17 system is any hexagon formed by mounting on opposite sides of a rectangle identical isosceles triangles as mirror images of one another. The two possible ways this can be done are shown in the template examples below, with the rectangle shown with dotted lines. Only four sides of the hexagon can be shaped, as indicated by the half-arrows. The template and any tile shape formed from it have two orthogonal axes of reflection symmetry as indicated by the dog pattern.
A single template forms a translation cluster.
A section of the tiling formed by the first template is shown below, with a translation cluster outlined. The two basic translations are indicated by the the vectors drawn from the highlighted cluster. The tiling has four types of centres of two-fold rotation symmetry, two types of axes of mirror reflection symmetry and two of glide reflection symmetry. An example of each of is indicated. The tiling symmetry group is cmm.
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