2.9" Purple, Stepped-Octahedral Fluorite on Quartz - Lupita Mine
This gorgeous specimen features purple fluorite with stepped-octahedral crystal growth, formed over a quartz matrix. It comes from the Lupita Mine in Durango, Mexico. Under shortwave ultraviolet light, the fluorite exhibits purple fluorescence.
Fluorite is a halide mineral comprised of calcium and fluorine, CaF2. The word fluorite is from the Latin fluo-, which means "to flow". In 1852 fluorite gave its name to the phenomenon known as fluorescence, or the property of fluorite to glow a different color depending upon the bandwidth of the ultraviolet light it is exposed to. Fluorite occurs commonly in cubic, octahedral and dodecahedral crystals in many different colors. These colors range from colorless and completely transparent to yellow, green, blue, purple, pink or black. Purples and greens tend to be the most common colors seen.