Aerinite

Aerinite (Ca4(Al,Fe,Mg)10Si12O35(OH)12CO3·12H2O) is a bright yellow to light brown inosilicate mineral. It crystallizes in the monoclinic system and occurs as fibrous masses and coatings. It has a vitreous luster, a specific gravity of 2.48 and a Mohs hardness of 3. It is a low temperature hydrothermal phase occurring in zeolite facies alteration of mafic rocks. Associated minerals include prehnite, scolecite and mesolite.Its name comes from a Greek root meaning "atmosphere" or "sky".
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General Information:
 Chemical Formula:
(Ca,Na)4Mg3(Fe+++,Fe++,Al)3[(Si,Al)O42](OH)6·n(H2O) (n~11.3)
 Composition:
(Molecular Weight = 1,854.54 gm)
Sodium 0.37 % Na
Calcium 8.00 % Ca
Magnesium 3.93 % Mg
Aluminum 6.11 % Al
Iron 8.43 % Fe
Silicon 20.44 % Si
Hydrogen 1.55 % H 
Oxygen 51.16 % O 
 Empirical Formula:
Ca3.7Na0.3Mg3Fe3+1.4Fe2+1.4Al4.2Si13.5O42(OH)6·11.3(H2O)
 Environment:
Alteration product in basalts and andesites. Hydrothermal zeolite.
 IMA Status:
Approved IMA 1986
 Locality:
TL: Spain, Caserras, Aragon and St. Pandelon, Landes, France.
 Name Origin:
Named from the Greek root "aer-", alluding to atmosphere or sky and hence the color, sky blue.
Physical Properties:
 Color:
blue, blue green, or sky blue.
 Density:
2.48
 Diaphaniety:
Translucent
 Habits:
Fibrous - Crystals made up of fibers., ,
 Hardness:
3 - Calcite
 Luster:
Vitreous (Glassy)
 Streak:
bluish white
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