Red Color of Ruby: The Science Behind the Brilliance

What gives rubies their brilliant red color?

A. Interaction of light with chromium atoms

B. Total internal reflection of light within the crystal

C. Both A and B

Answer:

C. Both A and B

Red rubies get their brilliant red color from a combination of factors. The primary reason behind their color is the interaction of light with chromium atoms present in the crystal structure of the ruby. These chromium atoms absorb most of the visible spectrum of light but reflect red light, giving the ruby its iconic red hue.

In addition to the interaction with chromium atoms, the total internal reflection of light within the crystal further enhances the ruby's brilliance. Similar to how a diamond sparkles due to its refractive index and facets, rubies can appear to almost glow because of the way light is refracted, internally reflected, and emitted.

It's essential to note that while impurities and structural defects in the crystal lattice can affect the color of gemstones like diamonds, the vibrant red color of rubies is primarily attributed to the specific interaction of light with chromium atoms.