Abstract: A T1-T2* measurement which permits speciation of different components with restricted mobility in samples where a T1-T2 measurement is impossible is disclosed. Tracking the T1-T2* coordinate, and associated signal intensity changes, can reveal additional structural and/or dynamic information such as phase changes in rigid/semi-rigid biopolymer samples or pore level changes in morphology of the water environments in cement-based materials. In another aspect, the T1-T2* measurement may also be employed to discriminate composition in solid mixtures, a very significant analytical problem in industry. In a further aspect, the T1-T2* measurement has particular value in permitting a simple assignment of T1 to different T2* populations.