General Information:
Chemical Formula:
ZnCO3
Composition:
(Molecular Weight = 125.40 gm)
Zinc 52.15 % Zn
Carbon 9.58 % C
Oxygen 38.28 % O
Empirical Formula:
Zn(CO3)
Name Origin:
Named after the English mineralogist, J. Smithson (1765-1829).
Physical Properties:
Cleavage:
[1011] Perfect, [1011] Perfect, 1011 Perfect
Color:
grayish white, dark gray, green, blue, or yellow.
Density:
4.4 - 4.5, Average = 4.45
Diaphaniety:
Subtransparent to translucent
Habits:
Botryoidal - "Grape-like" rounded forms (e.g.. malachite)., Reniform - "Kidney like" in shape (e.g.. hematite)., Earthy - Dull, clay-like texture with no visible crystalline affinitie s, (e.g. howlite).
Hardness:
4.5 - Between Fluorite and Apatite
Luminescence:
None.
Luster:
Vitreous (Glassy)
Streak:
white
More details...