Almandine(alpha)

Formula : Fe3Al2Si3O12

Family: 
Space group: 
Isometric - Hexoctahedral H-M Symbol (4/m 3 2/m) Space Group: I a3d
Dana class: 
51.4.3a.2 (51)Nesosilicate Insular SiO4 Groups Only (51.4) with cations in [6] and >[6] coordination (51.4.3a) Garnet group (Pyralspite series)
High temperature: 
Based on the garnet stability, almandine may be stable around 500C and less with the increase of pressure.
Geological context: 
The most common garnet, typically in mica schists and gneisses, from regionally metamorphosed argillaceous sediments and pelites; also in contact metamorphic hornfels and in granites

Dernière mise à jour le 25.01.2021

THERMODYNAMICS

T(°C) 0 25 60 100 150 200 250 300
log10K 49.39 42.18 33.63 25.68 17.69 11.11 5.39 0.07