This mobile app allows you to convert T2* and R2* values obtained with 1.5T and 3.0T MRI into both liver and myocardial iron concentrations (LIC and MIC) in mg/g.
The conversions are based on published manuscripts, which correlate the MRI value in ms/Hz into direct iron measurements, by biopsies.
The references to the conversation equations can be found in the information toolbox.