Fluor-uvite



Uvite (fluor-uvite) is a calcium magnesium aluminum boron silicate hydroxide mineral of the tourmaline group; sodium may substitute for calcium. Wet chemical analyses of a green Franklin uvite and of a brown uvite from an unknown locality assuredly in the local area indicate that Franklin uvite is near end-member composition, with limited substitution of Na for Ca, and with FeO less than 2.4 weight percent in all analyses. Boron isotope data for Sterling Hill-sited, marble-hosted uvites were given by Swihart and Moore (1989) and by Palmer and Slack (1989); both studies obtained generally similar values.
Uvite is by far the most common of the tourmaline species at Franklin. Much of the tourmaline described and figured by Palache (1935) is this species, a mineral of the Franklin Marble. Before the individual species were defined, such material often was called by the general name tourmaline. Uvite was redefined and established by Dunn et al. (1977).
Franklin uvite occurs in euhedral crystals up to 10 cm in dimension; most are equant in habit. The morphology was described in detail by Palache (1935). Franklin uvite is light green or light brown for the most part. Where color zoning is evident, it consists mostly of green outer zones on brown or lighter green cores; such outer zones are commonly quite thin, commonly of faint color, and rarely emerald green. The luster is vitreous; cleavage is absent; and the density is 3.05 g/cm3. The fluorescence in ultraviolet is orange-yellow in shortwave. Uvite, when massive, is differentiated from apatite by its superior hardness.
Franklin uvite occurs in the marble quarries of the area. Palache (1935) reported fine crystals from the Fowler quarry, where they occur in calcite with graphite, and from the Franklin Iron Company Quarry, where they are associated with titanite, arsenopyrite, pyrrhotite, pyrite, fluorite, and other minerals. Numerous crystals fitting Palache's descriptions were examined by [Dunn] and found to be uvite in each case (Dunn et al., 1977).
Uvite crystals were described by Palache (1935) from the hemimorphite deposit at Sterling Hill; he suggested they were introduced mechanically through weathering of surrounding marble.
Generally, uvite crystals occur isolated in white marble; there are few minerals occurring as associated megacrysts. As such, the specimens have strong esthetic appeal. Some have been carved in relief from the surrounding calcite. Uvite is among the most prized of the minerals found in the Franklin Marble. Many of the best specimens are at Harvard University. (Dunn, 1995)


 Location Found: Franklin (Type Locality) and Ogdensburg
     
 Mineral Note: The species uvite found in earlier Franklin Mineral Lists has been redefined by the IMA (2011) into two species, fluorine-dominant refers to fluor-uvite
 Year Discovered: 1929
     
 Formula: Ca(Mg3)MgAl5(Si6O18)(BO3)3(OH)3F
 Essential Elements: Aluminum, Boron, Calcium, Fluorine, Hydrogen, Magnesium, Oxygen, Silicon
 All Elements in Formula: Aluminum, Boron, Calcium, Fluorine, Hydrogen, Magnesium, Oxygen, Silicon
     
 IMA Status: Approved 2010
     
Fluorescent Mineral Properties

 Shortwave UV light: Moderately bright to weak orange-yellow
     
 To find out more about this mineral at minDat's website, follow this link   Fluor-uvite

     
The Picking Table References
 PT Issue and PageDescription / Comment
V. 57, No. 2 - Fall 2016, pg. 18Fluorescent Minerals of Franklin and Sterling Hill, N.J., Part 1, Richard C. Bostwick - Fluor-uvite
View IssueV. 45, No. 1 - Spring 2004, pg. 14The Art of Fluorescent Mineral Photography, With Special Attention to the Minerals of Franklin and Sterling Hill Photographing the More Popular Franklin and Sterling Hill Fluorescent Minerals - Uvite
View IssueV. 33, No. 2 - Fall 1992, pg. 11The Check List of Franklin-Sterling Hill Fluorescent Minerals - Uvite (Fluorescent Info)
View IssueV. 27 No. 2 - Fall 1986, pg. 10Minerals of the Franklin Quarry, Philip P. Betancourt, Tourmaline Group (uvite and/or dravite)
View IssueV. 21, No. 1 - March 1980, pg. 8Mineral Notes Research Reports, Uvite
     
No Images at this time.

     





All content including, but not limited to, mineral images, maps, graphics, and text on the Franklin-Ogdensburg Mineralogical Society, Inc. (FOMS) website is licensed under a
Creative Commons Attribution-NonCommercial 4.0 International License.
Creative Commons License