The active use of X-ray diffraction for investigating carbon materials began in the 1950s. A comprehesive review of early diffraction studies of amorphous blacks and coals was carried out by Ergun and Tiensuu [1], and for petroleum systems by Erdman and Wender [2]. Warren was the first to develop and correct the shape, position and intensity of bands with the dimensions of layers [3]. Labout showed that petroleum asphaltenes give the powder diffraction pattern characteristic of amorphous substances [4]. Nellensieyn was the first to observe the band corresponding to an interplanar distance of 0.35 nm and the similarity of this characteristic for petroleum asphaltenes and amorphous blacks [5].