RECTANGLE D’OR (“THE GOLDEN RECTANGLE”) is a new unique puzzle based on the golden number j  (“Phi”).
First, let’s remind you of the value of this number (see page 2 on the original problems booklet). This number has incredible properties (see page 2 on the original problems booklet). A perfect rectangle has its width (W) and length (L) respectively proportional to the numbers 1 and j (see page 2 on the original problems booklet). 

Apart from its esthetic aspect, the perfetc rectangle has other exciting properties. For instance, take a perfect rectangle, the dimensions of which are L= j and W=1. Take a 1 x 1 square off it and the remaining rectangle will still be a perfect one and so on and so forth (see page 2 on the original problems booklet). The last figure gives the first set of pieces. The centers of the successive squares that we have ended up with are joined by a line in the shape of an infinite spiral twirling towards a spot in the rectangle that is called the “golden spot.”

In the first set of pieces, we cut the rectangles as pictured page 2 of the original problems booklet. The eight triangles that we end up with have the same apex, which is also the “ golden spot ”. They make up the second set of pieces. These triangles also have many properties in which j can be found, should that be in their side-lengths, their angles or their areas. 

Thus we end up with twelve different and “ reversible ” pieces, as pictured page 3 of the original problems booklet. Let’s call the width of the initial perfect rectangle the “unit length.” The unit length of the whole puzzle is one decimeter (10 cm).  The unit length is generally 2.5 cm for the shapes you are challenged to build : it is represented as :---¹---: in order to show their size.

The solution to problem #1 is the initial shape of the puzzle (see last page). The other shapes should be built outside the wooden tray using all the triangles (pieces #1 to #8) and possibly one or more pieces from the set of pieces #9 to #12. In that case, and as an example, “+P10, 11, 12” would indicate that pieces 10, 11 & 12 should also be used. 

The difficulty level is indicated for some more difficult problems (see range of difficulty page 15). A solution to the problems marked with an “S” is provided (see page 13). The other problems always have at least one solution.

 Thanks to the many possible combinations of pieces, you can also build your own shapes, as long as they have the same area as the perfect rectangle if you’re going to use all the triangles. Page 14 is left blank for you to add your own designs. 

We wish you much pleasure with the exciting “RECTANGLE D’OR” puzzle !