Due to their limited length of structural coherence nanocryst. materials show very diffuse powder x-ray diffraction patterns that are difficult to interpret unambiguously. A combination of high-energy x-ray powder diffraction and at. pair distribution function anal. can be used to both assess the geometry (i.e., size and shape) and det. the internal at. ordering of nanocryst. materials in a straightforward way. As an example cubic γ-Fe2O3 nanosized crystals shaped as spheres and tetrapods are considered.