A method and system are provided for elementally detecting variations in density. The method includes providing a computed tomography device, comprising a radiation source, a detector, and at least one grating between the radiation source and the detector, positioning the component between the radiation source and the detector, directing radiation from the radiation source to the detector to acquire information from the component, generating at least one phase contrast image and at least one dark field contrast image of the component corresponding to variations in density with the information from the component, correlating the variations in density to a foreign mass, and displaying foreign mass distribution within the component. The system includes a radiation source, a detector, a component, a first grating, a second grating, and an analysis device capable of determining total variation of density in response to radiation received by the detector, and correlating the variation of density to free element distribution in the component.