Question

Explain the reason for glittering of diamond.

Answer 1

1. The diamond appears dazzling because the total internal reflection of light happens inside the diamond.
2. The refractive index of only diamonds is about 2.417. It is much larger than that for ordinary glass which is about only 1.5.
3. The critical angle of a diamond is about 24.4°. It is much less than that of glass.
4. A skilled diamond cutter makes use of this larger range of angle of incidence (24.4° to 90° inside the diamond), to ensure that light entering the diamond is total internally reflected from the many cut faces before getting out.
5. This gives a sparkling effect for diamond.