Mineralogist, Volume 97, pages 489–495, 2012 Veatchite: Structural relationships of the three polytypes...Crystal structures of the three polytypes of veatchite, Sr2B11O16(OH)5·H2O, are determined by X‑ray,... single-crystal studies. The polytypes are: veatchite-1A, triclinic space group P1, with a = 6.6378(6)...82.696(12), γ = 60.476(1)°, V = 809.7(2) Å3; veatchite-1M, monoclinic space group P21, with a = 6.7127(4)...6272(4) Å, β = 119.209(1)°, V = 805.4(2) Å3; and veatchite-2M,monoclinic space group Cc with a = 6.6070(3) |