From a suite of advanced magic-angle spinning (MAS) NMR spectroscopy and powder X-ray diffraction (PXRD) experiments, we present a comprehensive structural analysis of pyrophosphate-bearing calcium phosphate cements that are investigated for bone-inductive biomedical implants. The cements consist mainly of poorly ordered monetite (CaHPO4), along with minor Ca orthophosphate phases, and two distinct pyrophosphate constituents: crystalline beta-Ca2P2O7 and amorphous calcium pyrophosphate (ACPP), the latter involving one water bearing portion and another anhydrous component. Independent 2D MAS NMR experiments evidenced close contacts between the amorphous pyrophosphates and the monetite phase, where ACPP is proposed to form a thin layer coating the monetite particles. Heteronuclear H-1-P-31 and homonuclear P-31-P-31 correlation NMR experimentation enabled us to detect, identify, and quantify even minor cement constituents (less than or similar to 2 mol%) that could not be ascertained by the Rietveld method. Quantitative phase analyses of the cements, as determined independently by P-31 NMR and PXRD, are contrasted and discussed.