Fluorite (Purple) Beaded Bracelet

Fluorite is soft at Mohs 4 and cleaves easily, so store it away from harder stones and avoid knocks. Prolonged direct sunlight can fade its color. Because it contains fluoride, do not soak it or make elixirs by placing it directly in drinking water; use the indirect method instead.

Fluorite forms in veins and cavities where warm, mineral-rich fluids move through limestone and granite, often alongside quartz, calcite, barite and metallic ores. As those fluids cool, calcium and fluorine lock into cubes and octahedrons, and trace elements and natural radiation paint the ribbons of purple, green, blue and yellow that make each piece its own. The German scholar Georgius Agricola described it in 1530 under the name fluores, from the Latin fluere, to flow, because miners added it to ore to help the metal melt and flow during smelting.

Fluorite is calcium fluoride, chemical formula CaF₂, a halide mineral that crystallizes in the cubic system as cubes, octahedrons and interpenetrating twins. It defines 4 on the Mohs scale, has a vitreous luster and perfect octahedral cleavage, and ranges from transparent to translucent in nearly every color. Many specimens glow under ultraviolet light, and in 1852 George Gabriel Stokes coined the word fluorescence from the mineral's name.

• In Rome, luxurious murrhine cups, which many scholars believe were carved from fluorite, sold for fortunes, and later lore held that wine drunk from them would not intoxicate the drinker.
• Chinese legends of the night-shining pearl, a gem said to glow in the dark, are often traced to fluorite, whose Chinese name means firefly stone because some pieces glow when warmed.
• Derbyshire lore claims the Romans carved Blue John, a banded purple and yellow fluorite, into vases; the record shows it has been mined at Castleton since the 1700s and turned into vases and ornaments for Georgian country houses.