Question

what is the reason behind the shining of the diamond?how do you appreciate this phenomenon?​

Answer 1

Answer:

Total internal reflection is the main reason

For brilliance of diamonds. The critical angle of a diamond is very low (24.4o). So if a light ray enters a diamond it is very likely to undergo total internal reflection which makes the diamond shine.

The figure below illustrates the total internal reflection in diamond.

Answer 2

Explanation:

The sparkling isn't just the high refractive index - the shape matters too.Diamonds are cut so that a light ray falling on the diamond is reflected multiple times inside the diamond and therefore sends light out in all directions .Actually diamonds don't shine they reflect