Abstract: A method and apparatus for dating a body sample, such as blood, includes taking at least one spectroscopic measurement of the sample at at least two predetermined positions in the spectrum having spectral characteristics corresponding to at least two predetermined substances present in the sample that have a time varying relationship with each other. A measured relative concentration of each of the predetermined substances is then determined from the measurement, and the measured relative concentrations of the two predetermined substances is compared with a known variation of the relative concentrations of the two predetermined substances over time. A good fit of the measured relative concentrations to the known variation of the relative concentrations is then determined, so as to provide an indication of the age of the sample. Alternatively, instead of measuring the relative concentrations of each of the predetermined substances, the rate of change of the relative concentrations is determined.

Abstract: A method and apparatus for dating a dating a body sample, such as blood, includes taking at least one spectroscopic measurement (37) of the sample at least two predetermined positions in the spectrum having spectral characteristics corresponding to at least two predetermined substances present in the sample that have a time varying relationship with each other. A measured relative concentration of each of the predetermined substances is then determined (41) from the measurement, and the measured relative concentrations of the two predetermined substances is compared (43) with a known variation of the relative concentrations of the two predetermined substances over time. A good fit of the measured relative concentrations to the known variation of the relative concentrations is then determined, so as to provide an indication of the age of the sample (44).