Abstract: A system (300) for providing a three-dimensional computer tomography image of a gemstone, the system (300) comprising an X-ray source (330) for providing an X-ray towards a gemstone (320); an X-ray detector system for detecting X-rays transmitted through or diffracted by the gemstone (320). The X-ray detector system surrounds the gemstone (320) and detects a three-dimensional multi-angle X-ray diffraction pattern from the gemstone (320) upon rotation of the gemstone (320) within the X-ray field, and provides an output signal therefrom, wherein the output signal provides for invasive three-dimension multiangle X-ray diffraction reconstructed computed tomography from the three-dimension multiangle X-ray diffraction pattern.