Muscovite Mesto E, Scordari F, Lacalamita M, Schingaro E American Mineralogist 97 (2012) 1460-1468 Tobelite and NH4+ -rich muscovite single crystals from Ordovician Armorican sandstones (Brittany, France): Structure and crystal chemistry Note: sample musc_4 Locality: Ordovician Armorican sandstones, Brittany, France _database_code_amcsd 0019256 9.027 5.1999 20.616 90 100.113 90 C2/c atom x y z occ Uiso U(1,1) U(2,2) U(3,3) U(1,2) U(1,3) U(2,3) K 0 .1042 .25 .465 .029 .027 .024 .035 0 .0048 0 Na 0 .1042 .25 .03 .029 .027 .024 .035 0 .0048 0 Ba 0 .1042 .25 .01 .029 .027 .024 .035 0 .0048 0 N 0 .1042 .25 .36 .029 .027 .024 .035 0 .0048 0 H 0 .1042 .25 1.44 .029 .027 .024 .035 0 .0048 0 AlM2 .0830 .2500 .0001 .929 .0111 .013 .008 .013 .0007 .0029 .0020 SiT1 .1232 .5864 .1333 .782 .0128 .0117 .011 .016 .0012 .0036 .0007 AlT1 .1232 .5864 .1333 .218 .0128 .0117 .011 .016 .0012 .0036 .0007 SiT2 .2948 .1047 .13315 .782 .0144 .014 .011 .019 -.0020 .0053 -.0011 AlT2 .2948 .1047 .13315 .218 .0144 .014 .011 .019 -.0020 .0053 -.0011 O1 .0785 .558 .0528 .940 .015 O2 .2704 .137 .0528 .942 .016 O3 .1964 .318 .1659 .932 .017 O4 .4722 .148 .1652 .933 .020 O5 .2491 .813 .1539 .941 .022 OH6 .9567 .0597 .0490 .93 .012