Celadonite

Celadonite is a mica group mineral, a phyllosilicate of potassium, iron in both oxidation states, aluminium and hydroxide with formula: K(Mg,Fe2+)(Fe3+,Al)[Si4O10](OH)2.It crystallizes in the monoclinic system and usually forms massive aggregates of prismatic crystallites or in dull clay masses. It is soft with a Mohs hardness of 2 and a specific gravity of 3. Typically occurs as dull gray-green to bluish green masses. It forms vesicle fillings and linings in altered basaltic lavas.
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General Information:
 Chemical Formula:
K(Mg,Fe++)(Fe+++,Al)[Si4O10](OH)2
 Environment:
Vesicle lining and coatings in altered volcanics of intermediate to basic compostions.
 IMA Status:
Accepted IMA 1977
 Locality:
Mt. Baldo, near Verona, Italy.
 Name Origin:
Named from the French 'celadon,' sea-green, in allusion to its common color.
Physical Properties:
 Cleavage:
[001] Perfect
 Color:
gray green or bluish green.
 Density:
2.95 - 3.05, Average = 3
 Diaphaniety:
Translucent to opaque
 Habits:
Earthy - Dull, clay-like texture with no visible crystalline affinities, (e.g. howlite)., Aggregates - Made of numerous individual crystals or clusters., Encrustations - Forms crust-l ike aggregates on matrix.
 Hardness:
2 - Gypsum
 Luster:
Earthy (Dull)
 Streak:
greenish white
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