Nesquehonite

Magnesium carbonate, MgCO3, is a white solid that occurs in nature as a mineral. Several hydrated and basic forms of magnesium carbonate also exist as minerals. In addition, MgCO3 has a variety of applications.
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General Information:
 Chemical Formula:
Mg(HCO3)(OH)·2(H2O)
 Composition:
(Molecular Weight = 138.36 gm)
Magnesium 17.57 % Mg
Hydrogen 4.37 % H 
Carbon 8.68 % C 
Oxygen 69.38 % O 
 Empirical Formula:
Mg(HCO3)(OH)·2(H2O)
 Locality:
Coal mine at Nesquehoning, Schurlkill Co., Pensylvania, USA.
 Name Origin:
Named after its locality.
Physical Properties:
 Cleavage:
[110] Perfect, [001] Imperfect
 Color:
colorless or white.
 Density:
1.83 - 1.85, Average = 1.84
 Diaphaniety:
Transparent to translucent
 Habits:
Radial - Crystals radiate from a center without producing stellar forms (e.g. stibnite), Prismatic - Crystals Shaped like Slender Prisms (e.g. tourmaline).,
 Hardness:
2.5 - Finger Nail
 Luminescence:
Non-fluorescent.
 Luster:
Vitreous - Dull
 Streak:
white
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