2.5" Purple-Blue Cubic Fluorite Crystals - Inner Mongolia

This is a gorgeous cluster of blue-purple cubic fluorite crystals on a micro muscovite crystal encrusted matrix, collected from the Yindu Deposit in Inner Mongolia, China. The crystals have spots of deeper coloration peppered throughout the their interior.

Arsenopyrite and chalcopyrite crystals can be found across what could be considered the bottom of this specimen.

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.

Arsenopyrite is an iron arsenic sulfide with the chemical formula FeAsS. Depending on minerals present during formation, the iron can be replaced by cobalt (Cobaltite). Arsenopyrite is the most common mineral containing arsenic and can be found in igneous, metamorphic and sedimentary rock. Crystals can be found as prismatic, twinned, columnar, elongated and massive formations within veins and are found in locations all around the world.

Chalcopyrite is a brass-yellow colored mineral which is one of the most important ores of copper. When weathered chalcopyrite loses it's metallic luster, turning a gray-green color. When acids are present the tarnish can develop a red to blue to purple iridescence.

Fluorite, Arsenopyrite & Chalcopyrite
Yindu Deposit, Chifeng City, Inner Mongolia, China
2.5 x 1.8"