Yellow & Gold Crystals

What Makes Minerals Yellow & Gold?

Yellow in minerals most commonly comes from iron in specific oxidation states. Citrine's yellow is from Fe³⁺ color centers. Sulfur produces vivid yellow in native sulfur and bumble bee jasper. Gold's yellow is intrinsic - it results from relativistic effects on gold's electron orbitals that cause it to absorb blue light. Yellow topaz, yellow sapphire, and heliodor (yellow beryl) each achieve yellow through different trace element mechanisms.