Fluorite

= = =__**Fluorite:**__ =

http://www.mii.org/Minerals/photofluor.html http://www.minsocam.org/ammin/AM33/AM33_64.pdf []
 * Resource Links: **

[] > 1.** Properties: ** (chart by Mineral Zone- World MIneral Exchange: http://www.mineralszone.com/minerals/fluorite.html)
 * Video Links: THEY'RE SO MUCH FUN!**
 * Short video that serves as a visual introduction the the different types of Fluorite cryistal:
 * Video clip from our friends at the ADA (American Dental Association) extolling the virtues of Fluoride, a byproduct of Fluorite. []
 * Color || White or colorless, purple, blue, blue-green, yellow, brownish-yellow, or red. ||
 * Crystal habit || Occurs as well-formed coarse sized crystals. Also as massive - granular. ||
 * Crystal system || Isometric 4/m bar 3 2/m. ||
 * Cleavage || [111] Perfect, [111] Perfect, [111] Perfect. ||
 * Fracture || Uneven ||
 * Mohs Scale hardness || 4 ||
 * Luster || Vitreous ||
 * Refractive index || 1.433-1.435 ||
 * Streak || White ||
 * Specific gravity || 3.18 ||
 * Fusibility || 3 ||
 * Solubility || Slightly in water ||
 * Other || Sometimes phosphoresces when heated or scratched. Other varieties fluoresce beautifully. ||

2. **How is it used:** Fluorite is also used as a source of flourine in water and laboratory acid. Fluorite can be used instead of glass in high performance telescopes and camera lens. The name "flourite" comes from the Latin word "fluere" and refers to the fact that it melts easily, and so is also used to help lower the melting point of raw materials in steel production. In addition, fluorite is the main ingredient in // Fluoride, // used to clean and protect tooth enamel. We can all thank fluorite for making the dentist's office a terrible place to be. The United States government supplements the drinking water in the US with fluoride to help reduce birth defects among other problems.

3. **How much is used?** N/A

4. **What are the sources, and how is it extracted?**

The United States used to produce large quantities of the mineral fluorspar. However, the mines in Illinois-Kentucky fluorite district are now closed. The United States now imports fluorspar from countries such as China, South Africa, and Mexico. The fluorspar consumed in the United States is partially derived as a by-product of industrial processes like the uranium enrichment process, the refinement of petroleum, and in the treatment of stainless steel. Hydrofluoric acid (HF) and other types of fluorite are recovered during the production of aluminum.

5. **How rare is it? (i. e. how much “reserves”?)**

The world reserves of fluorite are estimated at 230 million tons, with the largest deposits in South Africa, Mexico, and China. Illinois was the largest producer of fluorite in the US until 1995, when the last mine closed in Illinois.

6. **Are there substitutes?** The substitutes are phosphoric acid plants. These plants process phosphate rock into phosphoric acid. They produce a derivative chemical called “fluorosilicic acid”. This acid is used to fluoridate public waters and/or to generate AlF3. Phosphate-rich rocks are a optional alternative source for rudimentary fluorine.

__By Schill and Yahn__