Major element compositions of granitic rocks from the Puy-les-Vignes deposit compared to the main peraluminous granitoids from the northwestern French Massif Central (FMC). (A) Alumina saturation diagram representing the molar ratio A/NK = Al₂O₃/(Na₂O + K₂O) as function of the molar ratio A/CNK = Al₂O₃/(CaO + Na₂O + K₂O. (B) B–A diagram representing the differentiation index B = Fe + Mg + Ti as function of the peraluminous index A = Al–(Na + K + 2Ca) expressed in millications (after Debon and Le Fort, 1983). The peraluminous granite fields of Villaseca et al. (1998) represent highly peraluminous granitoids (h-P), moderately peraluminous granitoids (m-P), low peraluminous granitoids (l-P), and highly felsic peraluminous granitoids (f-P). (C) P-Q diagram representing the relative proportion of feldspar P = K–(Na + Ca) as function of the quartz content Q = Si/3–(Na + K + 2Ca/3) expressed in millications (after Debon and Le Fort, 1983). (D) Total alkali-silica (TAS) diagram representing the Na₂O + K₂O vs. SiO₂ content (after Le Bas et al., 1986). Whole-rock compositions of the granitic rocks are reported in Table 1. Data sources: rare-metal granites and pegmatites: Aubert (1969), Mourey (1985), Cuney et al. (1992), Raimbault et al. (1995), Raimbault (1998), Raimbault and Burnol (1998); muscovite-bearing peraluminous granitoids: Gauthier (1973), Burnol (1974), Arniaud et al. (1984), Soufi (1988), Leger et al. (1990), Downes et al. (1997), Solgadi et al. (2007), Moyen et al. (2017), Villaros and Pichavant (2019); cordierite-bearing peraluminous granitoids: Downes and Duthou (1988), Williamson et al. (1996), Downes et al. (1997), Cartannaz (2005), Solgadi et al. (2007), Couzinié (2017), Moyen et al. (2017).