Fluorite (Calcium Floride)
Fluorite, Gibsonburg, Sandusky County, Ohio; N 5734
The name fluorite comes from the Latin word for flux, which refers to a substance that promotes flowing and combining of other materials, especially minerals and metals. And in fact the mineral fluorite is used as a flux in making steel and other metals that require the removal of impurities. Fluorite is a source of fluorine gas, which is used in the production of uranium. Some forms of fluorite crystals are used extensively in the study of light.
|Chemical Composition:||Calcium Floride (CaF2)|
|Crystal Habit:||Commonly well crystallized; sometimes two cubes grow together forming what are called penetration twins.|
|Specific Gravity:||3.0 - 3.3|
|Hardness:||4 — fluorite defines this level of the hardness scale.|
|Color:||Highly variable: colorless, yellow, light to dark brown, light to dark purple, pale green; rarely pink, rose, black; a single crystal may have more than one color (e.g. crystals with brown cores and colorless rims are common).|
|Transparency:||Transparent to translucent|
|Occurence:||<img width="195" height="172" title="Map of fluorite occurence" alt="Map of fluorite occurence" src="images/naturalHistory/minerals/fluoritemap.gif" />|
Although fluorite occurs throughout the world, the best sites for quantity and quality are in Europe and North America. Fluorite has been reported from 19 counties in Ohio.In northwestern Ohio fluorite crystals and granular aggregates are common in cavities of dolostone along the Findlay Arch. Near the Serpent Mound Disturbance in southwestern Ohio this mineral is present but rare.
- Carlson, Ernest H., ed. Minerals of Ohio; Ohio Division of Geological Survey, Columbus, OH; Bulletin 69; 1991.
- Pough, Frederick H. A Field Guide to Rocks and Minerals; Houghton Mifflin, Boston, MA; 1976.
- Sorrell, Charles A. Rocks and Minerals; Golden Press, New York, NY; 1973.