THE MAGIC CRYSTALS
a set of interchangeable
puzzles
 Here is an unusual set of toys. You can
easily recognize among them the Oriental "Hedgehog" puzzle,also called
"Diagonal star" which is at least 2000 years old. The others are fairly new. But
despite a solid age difference, they are all brothers.
 Each is assembled of 6 identical parts, but
the parts are interchangeable and can be assembled in any six compositions.
The reason is quite simple. The "Hedgehog" is a starlike form of a well known
polyhedron  the rhombic dodecahedron. It's a polyhedron with several starlike forms.
They are attained by elongating the sides of the "Hedgehog" to selfcrossing.
 These figures are remarkable indeed.
Choosing any six elements of them and assembling them in a whole, we get something
unexpected: however this "synthetic monster" can be asymmetrical, it would
always have exactly 12 sides, intersecting in most unusual ways.
 Other figures are produced by elongating the
sides of the elements to the points of intersection with cubes of various sizes or the
octahedron. Adding their parts to the other figures, the number of possible combinations
is 4 or 5digit (try to count).
