HOW DIAMONDS REFLECT LIGHT

The key to diamond cutting is to reflect as much light as possible

SHALLOW CUT

If the cut is too shallow, some light is refracted through, rather than reflected from, the bottom of the crystal.

IDEAL CUT

In an ideal case, all the light entering the diamond is reflected back out again, with none lost to refraction.

DEEP CUT

Here light reflected from one side is bounced across to the other side, where it is again lost through refraction.