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A program to calculate activities of mineral endmembers from chemical analyses (usually determined by electron microprobe).

AX is a program which takes mineral analyses in the form of either oxide weight percent or as cations per formula unit and calculates the activities of the mineral endmembers useful for thermodynamic computations. Errors are propagated from the probe data to the final activities. This program is designed for users wanting approximate activities to use for thermo-barometric calculations, and does not use very sophisticated models (output for each mineral phase lists the assumptions made in each calculation).

Updated Feb 2019: new AX62 for 2011 dataset and White et al (2014) a-x models. Fix for ternary feldspars. The old AX is still available in the download.

Oct 2015: Improved cpx & opx. See axNotes.pdf for details.

Sept 2014: fixed minor overestimate of Fe2 in epidotes. New additions: stilpnomelane, prehnite, pumpellyite 

Versions available: 

       download:  Mac OSX

       download:  Windows

       download:  Linux 

These downloads hold executables, sample input files and documentation explaining the use of the program for Mac, Linux and Windows.