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Mineral speciesFormula
 Amesite(Fe)Fe4Al2(Al2Si2)O10(OH)8 
Mineralogy
Family: Chlorite Group 
Space group: Triclinic - Pedial H-M Symbol (1) Space Group: C1 
Dana class: 7.1.2c.1 (71) Phyllosilicate Sheets of Six-Membered Rings (71.1) with 1:1 layers(71.1.2c)Serpentine group (Amesite subgroup) 
Geological context
High temperature: Around 100C to 600C C according Fe,Mg, Al substitutions. 
Geological context: A product of low-grade metamorphism of Al, Mg-rich rocks. 
Thermodynamics
Individual properties
Molar weight: 683.538 g/mol  ΔGºf-6,977,055 J/mol ref.  Sº: 514.80 J/mol/K ref. 
  ΔHºf-7,607,460 J/mol ref.  Cp: 540.47 J/mol/K ref. 
Reaction properties
Chemical reaction:  Amesite(Fe) + 20H+ = 4Al+3 + 4Fe+2 + 2H4SiO4 + 10H2O 
log10(Keq) = A + B.T + C.T-1 + D.log10(T) + E.T−2 (with T expressed in Kelvin)
A B C D E
 -3.37788394e+3   -5.39561729e-1   2.06769429e+5   1.21462840e+3   -9.17743531e+6 
Van t'Hoff
@ 25°C, 1 bar: log 10(Keq)57.03
ΔH°r-686,828 J/mol ref.
T (ºC) : 0 25 60 100 150 200 250 300
log 10(Keq):  68.03   57.03   44.41   32.89   21.40   11.96   3.69   -4.04 
Maier Kelley
Cp(T) = a + b*10-3T + C*105T-2 (with T expressed in Kelvin)  ref.
a:600.70 J/mol/K 
b:340.86 J/mol/K2 
c:-143.88 J.K/mol 

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