Eleven 9-cell Large Grain LG cavities have been produced and successfully RF tested at DESY. Analysis of the LG niobium discs for these cavities from the crystallographic orientation point of view will be presented. Surface behavior and roughness of the LG samples of different crystallographic orientation after buffered chemical polishing BCP have been studied by light microscope and Atom Force Microscope AFM. Oxidation behavior of large grain samples with different orientations after BCP was studied by X-ray photoelectron spectroscopy XPS and compared to polycrystalline niobium. The thickness of oxide layer on LG niobium is smaller than on fine grain material. The thickness of the oxide layer also depends on crystal orientation. Electron beam welding of LG samples has shown that two crystals grow in one crystal together, if the crystallographic orientations are matched at the EB seam. Relationship between the crystallographic orientation of the main central crystal of LG cavities and RF-data are analyzed. It seems that the orientations (221) and (211) is more preferable for cavity performance.