Ferropargasite

Formula : Na(Ca2Fe4Al)(Al2Si6)O22(OH)2

Family: 
Amphiboles
Space group: 
Monoclinic - Prismatic H-M Symbol (2/m) Space Group: C 2/m
Dana class: 
66.1.3a.13 (66) Inosilicate Double-Width Unbranched Chains, W=2 (66.1) Dana Type (66.1.3a) Group 2, the calcic amphiboles
High temperature: 
Stability domain limited near 300C to more 600C is also limited to high pressure, several kbar.
Geological context: 
In metamorphosed limestones and magmatc igneous rocks, metamorphosed ultramafic rocks,and in fresh magmatic igneous rocks.

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
961.993 279.890 (Ref.: 78hel/del) Helgeson, H.C., Delany, J.M, Nesbitt, H.W., and Bird, D.K., 1978. Summary and Critique of the Thermodynamic Properties of Rock Forming Minerals: Amer. J. Sci., 278A, 229 pp. -10569566 (Ref.: 78hel/del) Helgeson, H.C., Delany, J.M, Nesbitt, H.W., and Bird, D.K., 1978. Summary and Critique of the Thermodynamic Properties of Rock Forming Minerals: Amer. J. Sci., 278A, 229 pp. -11242757 (Ref.: Internal calculation) 776.132 (Ref.: 78hel/del) Helgeson, H.C., Delany, J.M, Nesbitt, H.W., and Bird, D.K., 1978. Summary and Critique of the Thermodynamic Properties of Rock Forming Minerals: Amer. J. Sci., 278A, 229 pp. 724.62 (Ref.: 78hel/del) Helgeson, H.C., Delany, J.M, Nesbitt, H.W., and Bird, D.K., 1978. Summary and Critique of the Thermodynamic Properties of Rock Forming Minerals: Amer. J. Sci., 278A, 229 pp.
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.
893.58 179.87 -197.86 (Ref.: 78hel/del) Helgeson, H.C., Delany, J.M, Nesbitt, H.W., and Bird, D.K., 1978. Summary and Critique of the Thermodynamic Properties of Rock Forming Minerals: Amer. J. Sci., 278A, 229 pp.
Reaction properties

Ferropargasite + 22H+ ⇌ 3Al+3 + 2Ca+2 + 4Fe+2 + Na+

298.15 K, 1 bar log10K: 83.84 ΔH°r:-811949 J·mol-1 (Ref.: Internal calculation)
T(°C) 0 25 60 100 150 200 250 300
log10K 96.60 83.84 68.73 54.74 40.76 29.35 19.48 10.33
log10K(T) = A + B·T + C·T-1 + D·log10(T) + E·T−2 (T in Kelvin)
A B C D E
-5690.499201 -0.817669 363317.925939 2028.462290 -19533575.554732