Valentinite

Valentinite is an antimony oxide mineral with formula Sb2O3. Valentinite crystallizes in the orthorhombic system and typically forms as radiating clusters of euhedral crystals or as fibrous masses. It is colorless to white with occasional shades or tints of yellow and red. It has a Mohs hardness of 2.5 to 3 and a specific gravity of 5.6 to 5.8. Valentinite occurs as a weathering product of stibnite and other antimony minerals. It is dimorphous with the isometric antimony oxide senarmontite.
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n. valentinite (Minerals)

General Information:
 Chemical Formula:
Sb2O3
 Composition:
(Molecular Weight = 291.50 gm)
Antimony 83.53 % Sb
Oxygen 16.47 % O 
 Empirical Formula:
Sb2O3
 Environment:
Occurs as an oxidation procuct of various antimony minerals.
 IMA Status:
Approved IMA 1960
 Locality:
South Ham, Wolfe Co., Quebec.
 Name Origin:
Named after the German alchemist, B. Valentinus (16th century).
Physical Properties:
 Cleavage:
[110] Perfect, [010] Distinct
 Color:
brownish reddish, colorless, gray white, grayish, or yellowish.
 Density:
5.6 - 5.8, Average = 5.69
 Diaphaniety:
Transparent
 Habits:
Euhedral Crystals - Occurs as well-formed crystals showing good external form., Divergent - Crystals radiate from a center without producing stellar forms., Striated - Parallel lines on crystal surface or cleavage face.
 Hardness:
2.5-3 - Finger Nail-Calcite
 Luminescence:
None.
 Luster:
Adamantine
 Streak:
white
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