Quantitative phase analyses (QPA) on a series of industrial Portland cements were performed using the Rietveld methods. The results were compared to those obtained from Bogue calculation in order to assess (if any) the correlations between this two techniques. In agreement with other recent reports, it appears that relationships having a general validity cannot be established. This finding reinforces the conclusion that the Rietveld method should be regarded as the most versatile and reliable technique for QPA of Portland cements.