Uvite

General Information:
 Chemical Formula:
(Ca,Na)(Mg,Fe++)3Al5Mg(BO3)3Si6O18(OH,F)4
 Composition:
(Molecular Weight = 970.23 gm)
Sodium 0.59 % Na
Calcium 3.10 % Ca
Magnesium 5.64 % Mg
Aluminum 13.90 % Al
Iron 4.32 % Fe
Silicon 17.37 % Si
Boron 3.34 % B 
Hydrogen 0.31 % H 
Oxygen 49.47 % O 
Fluorine 1.96 % F 
 Empirical Formula:
Ca0.75Na0.25Mg2.25Fe2+0.75Al5(BO3)3Si6O18(OH)3F
 Environment:
Pegmatitic and skarn rocks.
 Locality:
Province Uva, Sri Lanka.
 Name Origin:
Named after its locality.
Physical Properties:
 Cleavage:
[1011] Indistinct
 Color:
yellowish brown, brown, blackish brown, or bluish black.
 Density:
3.1 - 3.2, Average = 3.15
 Diaphaniety:
Translucent to opaque
 Habits:
Striated - Parallel lines on crystal surface or cleavage face., Prismatic - Crystals Shaped like Slender Prisms (e.g. tourmaline).,
 Hardness:
7.5 - Garnet
 Luminescence:
Piezoelectric.
 Luster:
Vitreous - Greasy
 Streak:
light brown
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