why glass does not show brilliance as diamonds

Sure, here's the explanation:

1. Refractive Index: The refractive index is a measure of how much a ray of light bends when it enters a material. Diamonds have a high refractive index (2.42), which means light bends significantly when it enters a diamond. This bending of light is what causes the brilliance and sparkle in diamonds. Glass, on the other hand, has a lower refractive index (1.5), so light doesn't bend as much, resulting in less brilliance.

2. Dispersion: Dispersion is the splitting of white light into its constituent colors. Diamonds have a high dispersion (0.044), which means they split light into a spectrum of colors, creating a "fire" effect. Glass has a lower dispersion, so it doesn't create the same effect.

3. Cut: Diamonds are usually cut in a way that maximizes their brilliance. They are often cut into a round brilliant shape, which has 58 facets (flat surfaces) that reflect light. Glass is usually not cut in this way, so it doesn't reflect light as effectively.

4. Internal Reflection: Due to their high refractive index, diamonds also have a high level of total internal reflection. This means that once light enters a diamond, it is likely to be reflected back out, rather than being absorbed or passing through. This adds to the brilliance of diamonds. Glass does not have the same level of internal reflection.

5. Material Structure: Diamonds are made of carbon atoms arranged in a crystal lattice structure, which contributes to their brilliance. Glass is an amorphous solid, meaning its atoms are not arranged in a regular pattern. This lack of structure can reduce the brilliance of glass.