AKF diagram

AKF diagram

[¦ā¦kā¦ef ′dī·ə‚gram]
(petrology)
A triangular diagram showing the chemical character of a metamorphic rock in which the three components plotted are A = Al2O3+ Fe2O3+ (CaO + Na2O), K = K2O, and F = FeO + MgO + MnO.