Phlogopite(Na)

Formula : NaMg3AlSi3O10(OH)2

Space group: 
Monoclinic - Prismatic H-M Symbol (2/m) Space Group: C 2/m
Dana class: 
71.2.2b.1 (71 )Phyllosilicate Sheets of Six-Membered Rings (71.2)with 2:1 Layers (71.2.2b)Mica Group (Biotite subgroup)
High temperature: 
Near 500C-600C in porphyries environnement to 1400C in metamorphic terranes, these stability temperatures are strongly aH2O -dependant.
Geological context: 
Phlogopite is present In metamorphosed dolostones and magnesium-rich limestones; also in ultramafic rocks as kimberlites, peridotites, lamproites, and serpentinites.

Dernière mise à jour le 25.01.2021

THERMODYNAMICS

Individual properties (298.15 K)
M
g·mol-1
 V°
cm3·mol-1
 ΔGºf
J·mol-1
 ΔHºf
J·mol-1
 Sº
J·mol-1·k-1
 CP
J·mol-1·K-1
401.151 144.500 (Ref.: 98hol/pow) Holland T.J.B., and Powell R., 1998. An internally consistent thermodynamic data set for phases of petrological interest. Journal of Metamorphic Geology, 16, p. 309 343. -5791214 (Ref.: Internal calculation) -6172140 (Ref.: 98hol/pow) Holland T.J.B., and Powell R., 1998. An internally consistent thermodynamic data set for phases of petrological interest. Journal of Metamorphic Geology, 16, p. 309 343. 318.000 (Ref.: 98hol/pow) Holland T.J.B., and Powell R., 1998. An internally consistent thermodynamic data set for phases of petrological interest. Journal of Metamorphic Geology, 16, p. 309 343. 354.30 (Ref.: 98hol/pow) Holland T.J.B., and Powell R., 1998. An internally consistent thermodynamic data set for phases of petrological interest. Journal of Metamorphic Geology, 16, p. 309 343.
CP(T) = a + b·T + ·c·T-2 (T in Kelvin)
a
J·mol-1·K-1
 b * 103
J·mol-1·K-2
 c * 10-5
J·K·mol-1
 Maier Kelley Ref.
416.95 143.58 -93.75 (Ref.: 98hol/pow) Holland T.J.B., and Powell R., 1998. An internally consistent thermodynamic data set for phases of petrological interest. Journal of Metamorphic Geology, 16, p. 309 343.
Reaction properties

Phlogopite(Na) + 10H+ ⇌ Al+3 + 3Mg+2 + Na+ + 3H4SiO4

298.15 K, 1 bar log10K: 44.20 ΔH°r:-384183 J·mol-1 (Ref.: 98hol/pow) Holland T.J.B., and Powell R., 1998. An internally consistent thermodynamic data set for phases of petrological interest. Journal of Metamorphic Geology, 16, p. 309 343.
T(°C) 0 25 60 100 150 200 250 300
log10K 50.25 44.20 37.08 30.58 24.20 19.09 14.75 10.77
log10K(T) = A + B·T + C·T-1 + D·log10(T) + E·T−2 (T in Kelvin)
A B C D E
-2779.108723 -0.387852 177864.478772 990.096874 -9560245.569361