A light source that's not only mathematically perfect, but
perhaps a little magical. People appear symmetrical, but even
the most perfect human face shows irregularities if we compare
the left side with the right. Perhaps this is why the absolute,
rigid symmetry of crystals seems beautiful yet alien to us.
Unlike DNA’s soft spiral, a crystal’s molecular bonds align
themselves to form regular three-dimensional structures, which
the Greeks considered mathematically pure. The most fundamental
of these shapes are known as the five Platonic solids. If you
assemble equal-sided triangles — all the same size, with the
same angles to each other — you can create three possible
solids: a tetrahedron (with 4 faces), an octahedron (8 faces),
and an icosahedron (20 faces). If you use squares instead of
triangles, you can create only a hexahedron, commonly known as a
cube. Pentagons create a dodecahedron (12 faces), and that’s as
far as we can go. No other solid objects can be built with all-
identical, equal-sided, equal-an