Nepouite

H₄Mg_0.24Ni_2.76O₉Si₂

Brindley, G.W.Wan, H.M.

a=5.29(2)Å   b=9.17(3)Å   c=7.26(2)Å

α=90.°   β=90.°   γ=90.°

Fe7 Mg1.2 (Al15 Si8 O40) (O H)12

Al₁₅Fe₇H₁₂Mg_1.2O₅₂Si₈

Harrison, F.W.Brindley, G.W.

Acta Crystallographica (1,1948-23,1967) (1957) 10, 77-82

a=9.52Å   b=5.47Å   c=18.19Å

α=90°   β=101.65°   γ=90°

Pyrophyllite-1Tc

Al₂O₁₁Si₄

Wardle, R.Brindley, G. W.

American Mineralogist (1972) 57, 732-750

a=5.1919Å   b=9.1224Å   c=9.4990Å

α=91.17°   β=100.21°   γ=88.62°