Powellite
“Fluorescent calcium molybdate”
Powellite is a calcium molybdate mineral that forms as a secondary mineral in the oxidation zones of molybdenum deposits. While rarely well-known outside mineral collecting circles, it's prized for its brilliant golden-yellow fluorescence under shortwave ultraviolet light.
calcium molybdate (CaMoO₄)
Deccan Traps zeolite cavities (India), Nasik (India), Randsburg (California, USA), Tonopah (Nevada, USA), Morocco
3.5-4
The finest powellite crystals in the world come from ancient lava flow cavities in India's Deccan Traps, where some transparent golden crystals reach over 5 cm and glow intensely under UV light.
Test Your Knowledge
What causes powellite's intense golden-yellow fluorescence under shortwave UV light?
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