American

Mineralogist

1996, Volume 81 November-December

AMERICAN MINERALOGIST, Volume 81, N11-12 1996

LETTERS

     Jiuhua Chen, Rui Li, John B. Parise, and Donald J. Weidner
     Pressure induced ordering in (Ni,Mg)2SiO4 olivine      1519

     Simon C. Kohn
     The solubility of water in nominally anhydrous mantle minerals using
     1H MAS NMR                                             1523

     Martin Kunz, Dimitrios Xirouchakis, Donald H. Lindsley, and Daniel
     Häusermann
     High pressure phase transition in titanite (CaTiOSiO4) 1527

     Bjorn Mysen
     Phosphorus speciation changes across the glass transition in
     polymerized alkali silicate glasses and melts          1531

ARTICLES

     Udo Becker, Michael F. Hochella Jr., and Edoardo Aprá
     The electronic structure of hematite {001} surfaces: Applications to
     the interpretation of STM images and heterogeneous surface reactions
                                                            1301

     J.F. Stebbins
     Magnesium site exchange in forsterite: A direct measurement by
     high-temperature 25Mg NMR spectroscopy                 1315

     C. Closmann, E. Knittle, and F. Bridges
     An XAFS study of the crystal chemistry of Fe in orthopyroxene 
                                                            1321

     Stuart A. Hayward and Ekhard K.H. Salje
     Displacive phase transition in anorthoclase: The plateau effect and
     the effect of T1-T2 ordering on the transition temperature 1332

     Piera Benna, Mario Tribaudino, and Emiliano Bruno
     The structure of ordered and disordered lead feldspar (PbAl2Si2O8)
                                                            1337

     Robert T. Downs, Aaron Andalman, and Marc Hudacsko
     The coordination numbers of Na and K atoms in low albite and
     microcline as determined from a procrystal electron-density
     distribution 1344

     Mark D. Welch, Paul F. Schofield, Gordon Cressey, and Chris J. Stanley
     Cation ordering in lead-molybdenum-vanadium oxychlorides 1350

     Huifang Xu and David R. Veblen
     Superstructures and domain structures in natural and synthetic
     kalsilite                                              1360

     Huifang Xu and Peter R. Buseck
     TEM investigation of the domain structure and superstructure in
     hillebrandite, Ca2SiO3(OH)2                            1371

     Ishmael Hassan
     Direct observation of phase transitions in aluminate sodalite,
     Ca8[Al12O24](CrO4)2                                    1375

     S.L. Cady, H.-R. Wenk, and K.H. Downing
     HRTEM of microcrystalline opal in chert and porcelanite from the
     Monterey Formation, California                         1380

     Huifang Xu, Yiqiang Zhang, and David R. Veblen
     Periodic and nonperiodic interstratification in the chlorite-biotite
     series                                                 1396

     LubomĚr Smrcok and LubomĚr Benco
     Ab initio periodic Hartree-Fock study of lizardite 1T  1405

     Tim Holland and Roger Powell
     Thermodynamics of order-disorder in minerals: I. Symmetric formalism
     applied to minerals of fixed composition               1413

     Tim Holland and Roger Powell
     Thermodynamics of order-disorder in minerals: II. Symmetric formalism
     applied to solid solutions                             1425

     Aurora Pun and James J. Papike
     Unequilibrated eucrites and the equilibrated Juvinas eucrite: Pyroxene
     REE systematics and major, minor, and trace element zoning
                                                            1438

     C. Waters and A.E. Boudreau
     A reevaluation of crystal-size distributions in chromite cumulates
                                                            1452

     Helen M. Lang
     Pressure-temperature-reaction history of metapelitic rocks from the
     Maryland Piedmont on the basis of correlated garnet zoning and
     plagioclase-inclusion composition                      1460-1475

     Raymond Jonckheere and Peter Van den haute
     Observations on the geometry of etched fission tracks in apatite:
     Implications for models of track revelation            1476

     Paola Bonazzi and Fiorenzo Mazzi
     Bottinoite, Ni(H2O)6[Sb(OH)6]2: Crystal structure, twinning, and
     hydrogen-bond model                                    1494

     Mizuhiko Akizuki, Yasuhiro Kudoh, and Takahiro Kuribayashi
     Crystal structures of the {011}, {610}, and {010} growth sectors in
     brewsterite                                            1501

     Marcus Nowak, Harald Behrens, and Wilhelm Johannes
     A new type of high-temperature, high-pressure cell for spectroscopic
     studies of hydrous silicate melts                      1507