Which term describes a defect that can influence absorption of visible light to produce color?

Which term describes a defect that can influence absorption of visible light to produce color?

• A. Band Gap
• B. Colored Lamellae
• C. Color Center
• D. Selective Absorption

Answer: (C)

Color centers are lattice defects that create localized energy states within the crystal’s band gap. These defect states allow electrons to absorb specific wavelengths of visible light to move between energy levels, so certain colors are removed from the spectrum and the stone appears colored. This mechanism directly ties color to a defect in the crystal structure, which is why this term is used to describe how absorption-driven color arises. The other terms describe broader concepts: the band gap is the general energy difference in a solid, not a defect itself; colored lamellae are growth-related features, not the defect mechanism for color; and selective absorption is the behavior of absorbing certain wavelengths, not the specific defect type responsible for color.

Color centers are lattice defects that create localized energy states within the crystal’s band gap. These defect states allow electrons to absorb specific wavelengths of visible light to move between energy levels, so certain colors are removed from the spectrum and the stone appears colored. This mechanism directly ties color to a defect in the crystal structure, which is why this term is used to describe how absorption-driven color arises.

The other terms describe broader concepts: the band gap is the general energy difference in a solid, not a defect itself; colored lamellae are growth-related features, not the defect mechanism for color; and selective absorption is the behavior of absorbing certain wavelengths, not the specific defect type responsible for color.