Analysis of Mineral Saturation Indices

Given accurate analyses and thermodynamic data, Saturation Indices can only show which minerals could conceivably precipitate from the solution (SI 0) (and could therefore be present in the system), and which minerals absolutely could not (SI 0). There are several reasons why many of the minerals which are calculated to be supersaturated may not actually be present in the system. 

On the other hand, many investigations have shown that Saturation Indices are a reasonably good guide to certain phases, such as some carbonate and sulfate minerals. Saturation Indices are also quite useful in reaction path modeling (Chapter 8) and inverse mass balance modeling (Chapter 9) in the sense that they indicate (within the accuracy of the data) which processes are possible (e.g., precipitation of a phase having an SI 0), and which are impossible (e.g., dissolution of a phase having an SI 0). 

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