Kate Jones will be adding more pieces to her site to surround the shapes that we are trying to reconstruct using the polyores of La Ora Stelo, but this time they will be concave shapes.

1) Take for example this star :

It has several angles of 216° (these are re-entrant angles); so that the border follows the sides of the shape, we will use these 2 pieces

The edge φ - 1 allows to transform an edge 1 into edge φ ; below these 3 edges have been colored :

For convex shapes this is of no interest, but let's look at the dimensions of the 216° angle :

The edge φ - 1 is combined with the angle of 216° in 4 different ways to adapt to the shape to be surrounded :

Now let's circle our star :

2) Take this other star :

It has angles of 252° ; we will then have to use this new part :

The 252° angle can also be combined with the edge φ – 1 in 4 different ways :

We can circle our second star :

3) Finally, let's take this 10-pointed star :

It has 10 angles of 288° ; the angle of 288° is so large and the outside angle so small that we cannot put a corner border with 2 sides of length 1 ; we are obliged to use one of the following 3 pieces :

Let's circle this new star :

4) To familiarize yourself with these new pieces (when they will be sold), go to exersise 6.