The brilliance of diamond is due to

Options

A. Reflection of light
B. Refraction of light
C. Total internal reflection of light
D. Diffraction of light

Answer

To determine the reason behind the brilliance of diamond, we can analyze the properties of light and how it interacts with the diamond's structure. Here’s a step-by-step solution:

### Step 1: Understand the properties of light
Light can undergo various phenomena when it interacts with different materials, including reflection, refraction, and dispersion. Each of these phenomena contributes to how we perceive the brilliance of a material.

**Hint:** Consider how light behaves when it hits a surface or passes through different mediums.

### Step 2: Identify the key phenomena contributing to brilliance
In the case of diamonds, the brilliance is primarily due to three key optical phenomena:
1. Reflection: The bouncing back of light when it hits a surface.
2. Refraction: The bending of light as it passes from one medium to another.
3. Dispersion: The separation of light into its component colors.

**Hint:** Think about how each of these phenomena affects the appearance of a gemstone.

### Step 3: Focus on total internal reflection
Among these phenomena, total internal reflection plays a crucial role in the brilliance of diamonds. This occurs when light traveling from a denser medium (diamond) to a less dense medium (air) hits the boundary at an angle greater than the critical angle, resulting in the light being completely reflected back into the diamond.

**Hint:** Recall the conditions required for total internal reflection to occur.

### Step 4: Consider the refractive index of diamond
Diamonds have a high refractive index, which means they bend light significantly. This high refractive index, combined with the diamond's cut and internal structure, allows light to reflect multiple times within the diamond before exiting, enhancing its brilliance.

**Hint:** Reflect on how the refractive index influences the behavior of light in different materials.

### Step 5: Conclusion
The brilliance of diamonds is primarily due to total internal reflection, which is facilitated by their high refractive index and unique structure. This phenomenon allows light to be reflected multiple times inside the diamond, creating a sparkling effect that is characteristic of diamonds.

**Final Answer:** The brilliance of diamond is due to **total internal reflection**.