Fluorite
Fluorite Gemstone Knowledge
For such an exquisitely beautiful gemstone, the name 'fluorite' has rather unglamorous origins, the word being derived from the Latin term 'fluere' (Eng: to flow) .. yes, fluorite was originally used as a flux in olden day iron smelting! Nowadays, gemstone connoisseurs love this collector's gem for its range of spectacular colours, from rich vivid purple and blues, to sublime spring greens and yellows - there's even a rare type that changes colour depending on the type of light it's under. In the 19th Century, when UV / light spectrum's were being discovered by science, the term 'fluorescent' was named after fluorite, due to some specimens glowing under certain light conditions (though note that a lot of fluorite doesn't glow under UV light; only those specimens which have traces of particular elements exhibit a glow). Fluorite is a soft gemstone, being only 4 on the MOHS hardness scale, so is not really suitable for robust daily wear as it may scratch and chip over time (less often/ occasional wear is fine).
About Blue John Fluorite
Blue John Fluorite is a unique and distinctive form of fluorite found in the Derbyshire area of England, UK. No one quite knows where the distinctive name "Blue John" came from; some say it is because the mineral is blue in the mine and turns a purple colour on exposure to sunlight (which makes sense as other types of fluorite can be UV sensitive too), while many people believe the name to have originated from the French words "bleu" and "jaune," which mean "blue" and "yellow," respectively. However, it's also worth noting that an old Cornish language word for fluorite is apparently "bleujenn", which would also make sense as I've read that a few hundred years ago there were Cornish miners who worked in the Derbyshire area who mined for lead.
The mineral is formed by a series of complex geological processes, which include the presence of fluorine-rich fluids in the geological environment. With changes in temperature and pressure, fluorite began to crystallize from these fluids, forming in veins, fractures and cavities within the rocks present in the environment. Other geological processes (such as tectonic activity), led to the later uplifting and exposure of these mineralized rocks to the Earth's surface, with erosion over a great many years exposing the Blue John Fluorite veins.
The distinct banding and color patterns within Blue John are believed to be influenced by various factors, including the presence of trace elements and impurities during the crystal's growth (some research suggests the distinctive colour is caused by colloidal calcium ie, calcium particles that are dispersed in a liquid, creating a colloidal suspension). The mining of this rare type of fluorite has been a traditional industry in the beautiful Derbyshire area for centuries, contributing to the mineral's cultural and historical significance in the region.
Blue John Fluorite is a soft gemstone, being only 4 on the MOHS hardness scale, so is not really suitable for robust daily wear as it may scratch and chip over time (less often/ occasional wear is fine).
Fluorite care
Store it away from other gems to avoid it being scratched, wrap it up well to avoid prolonged exposure to the light (some fluorite will fade if kept in direct sunlight for a long period of time) and clean by gently wiping it with a damp cloth, drying immediately afterward. Try not to expose it to heavy knocks as this may crack the stone. Avoid using silver polish or abrasives near any type of fluorite, as they may scratch it.