Why do diamonds sparkle so brightly?
Show answer & explanation
Answer: High refractive index and cuts
Surface is perfectly smooth — Wrong. Polishing helps, but sparkle comes from diamond's high refractive index and faceted cuts causing total internal reflection.
Color creates the sparkle — Wrong. Most diamonds are colorless. Sparkle comes from refractive index (2.42—very high) and cut facets reflecting/refracting light.
High refractive index and cuts ✓ — Correct! Diamonds have exceptional refractive index (2.42) meaning light bends sharply when entering. Precise facet cuts maximize total internal reflection—light bounces inside multiple times before exiting. This creates brilliance (white light return) and fire (dispersion into colors). Cut quality matters most for sparkle!
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