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Table 2 Composition of sheet silicates, muscovite, biotite and chlorite

From: Bristen granite: a highly differentiated, fluorite-bearing A-type granite from the Aar massif, Central Alps, Switzerland

Mineral Muscovite Muscovite Muscovite Muscovite Biotite Biotite Chlorite Chlorite Chlorite Chlorite
Geol. unit Brgr Brgr Brgr cAgr Brgr cAgr Brgr Brgr Brgr cAgr
# Points 16 1 1 4 15 10 17 1 1 10
Assemblage    ps     Matrix ps Chl-Ab vein  
SiO2 47.95 46.30 43.92 47.85 34.25 35.79 22.71 22.81 22.45 25.38
TiO2 0.16 0.28 0.31 0.01 1.03 1.57 0.06 0.15 0.07 0.06
Al2O3 28.96 28.46 27.07 29.79 17.45 16.2 19.42 18.93 20.11 18.73
FeO 7.45 8.38 8.81 4.25 31.48 24.36 43.43 41.45 42.36 32.11
MnO 0.11 0.18 0.26 0.04 0.55 0.54 1.36 2.03 2.15 1.04
MgO 0.58 0.58 0.57 1.90 0.99 7.59 1.03 1.4 1.31 10.37
CaO 0.02 0.02 1.56 bd 0.04 0.06 0.04 0.08 0.04 0.07
Na2O 0.10 0.08 0.11 0.18 0.09 0.06 0.04 0.03 bd 0.03
K2O 10.27 10.94 10.66 10.83 8.71 9.08 0.07 0.09 0.01 0.03
F 0.55 0.45 0.41 0.11 0.45 0.34 bd bd bd bd
Totald 94.74a 94.26 92.29 94.16b 93.82 94.48c 88.16 86.33 88.51 87.82
Oxygen 22 22 22 22 22 22 28 28 28 28
Si 6.543 6.429 6.308 6.503 5.585 5.598 5.344 5.415 5.247 5.583
Al(IV) 1.457 1.571 1.692 1.497 2.415 2.402 2.656 2.585 2.753 2.417
sum T 8.000 8.000 8.000 8.000 8.000 8.000 8.000 8.000 8.000 8.000
Ti 0.016 0.029 0.033 0.001 0.126 0.185 0.011 0.027 0.012 0.010
Al(VI) 3.200 3.086 2.890 3.274 0.938 0.584 2.732 2.711 2.788 2.440
Fe(II) 0.850 0.973 1.058 0.483 4.292 3.186 8.547 8.227 8.279 5.907
Mn 0.013 0.021 0.032 0.005 0.076 0.072 0.271 0.408 0.426 0.194
Mg 0.118 0.120 0.122 0.385 0.241 1.770 0.361 0.495 0.456 3.400
Ca 0.003 0.003 0.240 0.007 0.010 0.010 0.020 0.010 0.016
sum M 4.200 4.232 4.375 4.148 5.680 5.807 11.932 11.888 11.971 11.967
Na 0.026 0.022 0.031 0.047 0.028 0.018 0.018 0.014 0.013
K 1.788 1.938 1.953 1.877 1.812 1.812 0.021 0.027 0.000 0.008
sum I 1.814 1.960 1.984 1.924 1.840 1.830 0.039 0.041 0.000 0.021
F 0.237 0.198 0.186 0.047 0.232 0.168
XFe 0.88 0.89 0.90 0.56 0.95 0.64 0.96 0.94 0.95 0.63
  1. ps Ms + Chl pseudomorph after Bt, bd below detection limit
  2. Total includes: a0.25 Rb2O; b0.52 BaO; c0.11 BaO; d correction for O=F,Cl; traces of Cl in micas; Ms contains 15, 21, 25, 27 Cel