Zultanite’s color change is produced by trace iron (Fe³⁺) substituting into the aluminum site of the diaspore lattice, with chromium (Cr³⁺) contributing additional absorption in the red region. The combined absorption spectrum has transmission windows in green and red. Under daylight (rich in blue/green wavelengths), the green window dominates the perceived color. Under candlelight (rich in red/orange wavelengths), the red window dominates.

Why this matters

This is one of the cluster support articles for the Zultanite pillar. Each support addresses a single question that buyers, researchers, and writers actually ask, and connects back to the verified properties documented in the property guides.

The verified facts

Mineral species: diaspore (α-AlO(OH)). Locality: İlbir Mountains, Muğla Province, southwestern Türkiye. Hardness: 6.5–7 Mohs. Refractive index: 1.682–1.752. Specific gravity: 3.30–3.39. Color change: sage-green daylight to raspberry-pink candlelight, often through a champagne-gold indoor phase.

Where to read more

See the related property guides on hardness, refractive index, specific gravity, color change, and pleochroism for the verified values behind each claim.