Warwickite

Warwickite is an iron magnesium titanium borate mineral with formula: (MgFe)3Ti(O,BO3)2 or Mg(Ti,Fe3+,Al)(BO3)O. It occurs as brown to black prismatic orthorhombic crystals which are vitreous and transparent. It has a Mohs hardness of 3 to 4 and a specific gravity of 3.36. It was first described in 1838 near Warwick, Orange County, New York.
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(n.)
A dark brown or black mineral, occurring in prismatic crystals imbedded in limestone near Warwick, New York. It consists of the borate and titanate of magnesia and iron.
  

General Information:
 Chemical Formula:
Mg(Ti,Fe+++,Al)(BO3)O
 Composition:
(Molecular Weight = 206.10 gm)
Magnesium 11.79 % Mg
Titanium 13.94 % Ti
Aluminum 1.31 % Al
Iron 8.13 % Fe
Boron 10.49 % B 
Oxygen 54.34 % O 
 Empirical Formula:
MgTi0.6Fe3+0.3Al0.1(BO3)O
 Locality:
Southwest of Edenville, in the town of Warwick, Orange Co., New York.
 Name Origin:
Named after its locality.
Physical Properties:
 Cleavage:
[100] Perfect
 Color:
brown or black.
 Density:
3.36
 Diaphaniety:
Transparent to Subtranslucent
 Habits:
Prismatic - Crystals Shaped like Slender Prisms (e.g. tourmaline)., Crystalline - Fine - Occurs as well-formed fine sized crystals.,
 Hardness:
3-4 - Calcite-Fluorite
 Luminescence:
Non-fluorescent.
 Luster:
Vitreous - Silky
 Streak:
bluish black
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