Kyanite

Formula : Al2SiO5

Space group: 
Triclinic - Pinacoidal H-M Symbol ( 1) Space Group: P1
Dana class: 
52.2.2c.1 (52) Nesosilicate Insular SiO4 Groups and O, OH, F, and H2O (52.2 )with cations in [4] and >[4] coordination (52.2.2c) Al2SiO5 Kyanite subgroup)
High temperature: 
Stable in the range of200 to 800C. Its stability depends also on pressure.
Geological context: 
Metamorphic aluminous rocks, aluminous magmas

Dernière mise à jour le 11.06.2018

THERMODYNAMICS

Individual properties (298.15 K)
M
g·mol-1
cm3·mol-1
ΔGºf
J·mol-1
ΔHºf
J·mol-1
J·mol-1·k-1
CP
J·mol-1·K-1
162.046 44.090 -2430720 -2581169 83.680 121.06
Reaction properties

Kyanite + 6H+ ⇌ 2Al+3 + H4SiO4 + H2O

298.15 K, 1 bar log10K: 15.93 ΔH°r: -242655 J·mol-1
T(°C) 0 25 60 100 150 200 250 300
log10K 19.80 15.93 11.44 7.28 3.07 -0.44 -3.53 -6.41