The preparation and characterization of cordierites based on the commercial vermiculites obtained from the powder mixtures containing talc, kaolinite and vermiculite in the composition close to the cordierite 2MgO∙2Al₂O₃∙5SiO₂ has been reported since 2009. The aim of this paper was to characterize the structural properties of the nine synthetic cordierites sintered from the pre-ceramic mixtures containing commercial vermiculites at 1300° C in comparison with the orthorhombic natural and synthetic hexagonal cordierites (indialites) selected from literature. The orthorhombic natural cordierites showed the elements Fe and Mn replacing Mg in an appropriate correlation F = (Fe+Mn)/(Fe+Mn+Mg) with the unit cell parameter a, and an inverse correlation with parameter c. The unit cell parameters c calculated for the nine synthetic cordierites based on vermiculites (Ver) were in good linear relation with the FVer = (Fe/(Fe+Mg)oct + (K+Na+Ca)int) per formula unit of the corresponding vermiculites in the pre-ceramic mixtures. The structural disorder of cordierites based on vermiculites was determined higher, according to the wide index W1/3 of (211) reflection varying in a narrow range W1/3(211) from 0.290° to 0.299° 2Θ, in comparison with the W1/3(211) = 0.324° 2Θ of the cordierites based on the alumina.