Fluorite

Fluorite is an amazing mineral beloved by many collectors worldwide.

It occurs in quite a few different colours – yellows, greys, clear, blue, greens, purples.. the crystal formations it grows into can be pretty fascinating too. The ‘etched’ cubic crystals are extremely interesting.

There are too many classic Fluorite locales around the world for me to even come close to listing them in a brief piece of text. In the UK, however, County Durham Fluorite is among the most beloved by collectors.


Appearance, Uses and History

Fluorite is the mineral form of calcium fluoride.

In industry, it is used as a flux for smelting, and a source of fluoride. The industrial term is ‘fluorspar’, while ‘fluorite’ is typically used in a geological and mineralogical context.

It is used in the manufacture of hydrofluoric acid, a reasonably terrifying acid. The material is also used for optics – optically clear pieces of fluorite do not exhibit as much chromatic aberration as other materials and are excellent for use in microscopes, telescopes, and the ultraviolet/infrared ranges.

It can also be used in the manufacture of certain glasses and enamels.

It is worth taking a moment to clarify the differences between fluorite, fluoride, and fluorine – a single letter makes quite a difference!

  • Fluorine is a chemical element, number 9 on the periodic table.
  • Fluoride is a naturally occurring mineral, often used to help with dental health.
  • Fluorite is a naturally occurring crystalline mineral.

Fluorite gives its name to the phenomenon of fluorescence, a form of luminescence exhibited by many Fluorite specimens.

Fluorite is loved by collectors due to its wide range of bright colours, and fascinating crystalline formations – it has, in fact, been dubbed ‘the most colourful mineral in the world’. I’m sure Tourmaline would have something to say, but…

British Fluorite is extremely popular worldwide, with Fluorite specimens from County Durham and Derbyshire considered exceptional.

There are, of course, numerous jewellery and lapidary usages of Fluorite. There are numerous excellent carvings of the stone found, including Roman cups and chalices.

It is relatively soft, and therefore not ideal for jewellery usage, but Fluorite cabochons and beads are quite common. Jewellery containing Fluorite should ideally be designed to protect the stone.


Locales

Fluorite is extremely common with locales in almost every country.

Fine specimens are found in Argentina, Austria, Belgium, Brazil, Canada, China, Czechia, France, Germany, India, Mexico, Morocco, Namibia, Norway, Pakistan, Poland, Portugal, Spain, Tunisia, the UK, and the USA.

 


Mineralogy

Chemistry
A halide – Calcium Fluoride, with the formula CaF2
Colours and Variations
Purple, yellow, green, clear, aqua, blue, brown, gold, black, rainbow, banded. Colour zoning and banding are common.
Streak
White
Luster
Vitreous, dull
Fracture
Splintery, sub conchoidal
Transparency
Transparent, translucent.
Crystal habit
Isometric cubic crystals, although octahedral are not uncommon.
Massive, crystalline, nodular, botryoidal, granular, octahedra, massive.
Mohs hardness
4
Specific Gravity
3.0 – 3.3
Easiest testing method
Visual inspection – colour banding and zoning, distinct crystalline formation, and low hardness are all helpful indicators.
Common Treatments
None, although rarely irradiated.

Photos of Fluorite

Barite-Fluorite-elm44a
Fluorite-197397
Fluorite Taihang Shan ROM

Fluorine, calcite 2
Fluorit. China...2H1A6986ОВ
Fluorite La Charbonnière MNHN Minéralogie n2

Fluorite-158429
Fluorite-189397
Fluorite-192567

Fluorit Berbes Mine
Fluorine (Mexique) 10
Aragonite-Fluorite-cflu02a

6fluorite-douglass95
3192M-fluorite1
Fluorite, quartz 7100.FS2014

Fluorite, calcite 300-4-2401
Dolomite-Fluorite-cflo30x
9104 - Milano - Museo storia naturale - Fluorite - Foto Giovanni Dall'Orto 22-Apr-2007

Hazards and Warnings

Fluorite is safe to handle, and while it does contain Fluorine, this is not typically a risk factor.

Powdered Fluorite mixed with concentrated Sulphuric acid can produce hydrofluoric acid, which is very dangerous – but realistically, you’re probably not going to be powdering it and mixing it with acids!

Almost all rocks, minerals (and, frankly, almost all other substances on earth) can produce toxic dust when cutting, which can cause serious respiratory conditions including silicosis.

When cutting or polishing rocks, minerals, shells, etc, all work should be done wet to minimise the dust, and a suitable respirator or extraction system should be used.


Translations

Arabic:

  • فلورايت
  • الفلوريت
  • الفلورسبار
  • الفلوريت معدن متبلور

Hindi:

  • फ्लोराइट
  • एक प्रकार का धात्विया

Portuguese:

  • fluorita
  • espatoflúor

Bengali:

Indonesian:

  • fluorit

Punjabi:

  • ਫਲੋਰਾਈਟ
  • ਫਲੋਰਸਪਾਰ

English:

  • fluorite
  • fluorspar

Italian:

Russian:

  • Флюорит
  • плавиковый шпат

French:

  • la fluorine
  • spath fluor

Japanese:

  • 蛍石

Spanish:

  • Fluorita
  • Espato fluor

German:

  • Flussspat
  • Fluorit
  • Flußspat

Korean:

  • 형석

Thai:

Gujurati:

  • ફ્લોરાઇટ

Mandarin and Traditional Chinese:

  • 软水紫晶
  • 萤石
  • 螢石

Urdu:

  • فلورائٹ
  • فلورسپار

Further Reading / External Links