A method of radiological examination of an object for the identification and detection of the composition of the object comprising the steps of: irradiating an object under test with x-rays and collecting radiation emergent from the object at a suitable detector system in such manner that emergent radiation intensity data is collected for the entire volume of the object under test; numerically processing the radiation intensity data to obtain a first data item comprising a measure of the total number of electrons within the sample by performing a calculation derived from the radiation absorption integrated over a whole detection area A which calculation includes the following steps: performing a series of transmission measurements to determine a radiation transmission, T according to the relationship T = I I o where I is output intensity of a beam of incident intensity I 0 emerging from a medium; considering the linear attenuation coefficient ( μ) of a material at a given energy as μ ∝ ρ e and setting β as the constant of proportionality to the electron density ρ e such that μ = βρ e; based on the Beer Lambert equation for the output intensity I of a beam at a given energy emerging from a medium of thickness t having incident intensity I o, whereby the transmission T is given by T = I I o = e − μt hence ln T = − βρ e t integrating over a whole detection area A according to the following principles: − ∫ βρ r t dA = ∫ ln T dA ∫ t dA = V ρ e = N e V N e = − 1 β ∫ ln T dA where Vis the volume of the sample under investigation and N e is the number of electrons within that sample; thereby determining the total number of electrons within the sample, applying an alternative method to obtain a second data item correlated to another property of the sample; using the first and second data items to derive an indication of the material content of the sample. irradiating an object under test with x-rays and collecting radiation emergent from the object at a suitable detector system in such manner that emergent radiation intensity data is collected for the entire volume of the object under test; numerically processing the radiation intensity data to obtain a first data item comprising a measure of the total number of electrons within the sample by performing a calculation derived from the radiation absorption integrated over a whole detection area A which calculation includes the following steps: performing a series of transmission measurements to determine a radiation transmission, T according to the relationship T = I I o where I is output intensity of a beam of incident intensity I 0 emerging from a medium; considering the linear attenuation coefficient ( μ) of a material at a given energy as μ ∝ ρ e and setting β as the constant of proportionality to the electron density ρ e such that μ = βρ e; based on the Beer Lambert equation for the output intensity I of a beam at a given energy emerging from a medium of thickness t having incident intensity I o, whereby the transmission T is given by T = I I o = e − μt hence ln T = − βρ e t integrating over a whole detection area A according to the following principles: − ∫ βρ r t dA = ∫ ln T dA ∫ t dA = V ρ e = N e V N e = − 1 β ∫ ln T dA where Vis the volume of the sample under investigation and N e is the number of electrons within that sample; thereby determining the total number of electrons within the sample, performing a series of transmission measurements to determine a radiation transmission, T according to the relationship T = I I o where I is output intensity of a beam of incident intensity I 0 emerging from a medium; considering the linear attenuation coefficient ( μ) of a material at a given energy as μ ∝ ρ e and setting β as the constant of proportionality to the electron density ρ e such that μ = βρ e; based on the Beer Lambert equation for the output intensity I of a beam at a given energy emerging from a medium of thickness t having incident intensity I o, whereby the transmission T is given by T = I I o = e − μt hence ln T = − βρ e t integrating over a whole detection area A according to the following principles: − ∫ βρ r t dA = ∫ ln T dA ∫ t dA = V ρ e = N e V N e = − 1 β ∫ ln T dA where Vis the volume of the sample under investigation and N e is the number of electrons within that sample; thereby determining the total number of electrons within the sample, applying an alternative method to obtain a second data item correlated to another property of the sample; using the first and second data items to derive an indication of the material content of the sample.