American

Mineralogist

ARTICLES

J.D. Kubicki, G.A. Blake, and S.E. Apitz

Ab initio calculations on aluminosilicate Q³ species: Implications for atomic structures of mineral surfaces and dissolution mechanisms of feldspars 789

I. Tsatskis and E.K.H. Salje

Time evolution of pericline twin domains in alkali feldspars: A computer simulation study 800

Tullio Pilati, Francesco Demartin, and Carlo Maria Gramaccioli

Lattice-dynamical evaluation of atomic displacement parameters of minerals and its implications: The example of diopside 811

D. Andrault, J.-P. Itié, and F. Farges

High-temperature structural study of germanate perovskites and pyroxenoids 822

Paola Comodi and Pier Francesco Zanazzi

Effects of temperature and pressure on the structure of lawsonite 833

M. Chiara Domeneghetti, Vittorio Tazzoli, Tiziana Boffa Ballaran, and G. Mario Molin

Orthopyroxene from the Serra de Magé meteorite: A structure-refinement procedure for a Pbca phase coexisting with a C2/c exsolved phase 842

Paul F. Schofield, Kevin S. Knight, and Iona C. Stretton

Thermal expansion of gypsum investigated by neutron powder diffraction 847

Victor A. Drits and Douglas K. McCarty

The nature of diffraction effects from illite and illite-smectite consisting of interstratified trans-vacant and cis-vacant 2:1 layers: A semiquantitative technique for determination of layer-type content 852

Anne Sery, Alain Manceau, and G. Neville Greaves

Chemical state of Cd in apatite phosphate ores as determined by EXAFS spectroscopy 864

P. Bonazzi, S. Menchetti, G. Pratesi, M. Muniz-Miranda, and G. Sbrana

Light-induced variations in realgar and B-As₄S₄: X-ray diffraction and Raman studies 874

Lian-Kun Sha and Bruce W. Chappell

Two-site multi-cation ordering-disordering in minerals: An alternative kinetic model 881

Christelle Demars, Maurice Pagel, Etienne Deloule, and Philippe Blanc

Cathodoluminescence of quartz from sandstones: Interpretation of the UV range by determination of trace element distributions and fluid-inclusion P-T-X properties in authigenic quartz 891

Brigitte Wopenka, Bradley L. Jolliff, Ernst Zinner, and Daniel T. Kremser

Trace element zoning and incipient metamictization in a lunar zircon: Application of three microprobe techniques 902

Maria Franca Brigatti, Luca Medici, Emilio Saccani, and Carmela Vaccaro

Crystal chemistry and petrologic significance of Fe³⁺-rich phlogopite from the Tapira carbonatite complex, Brazil 913

Ulrich Klein, John C. Schumacher, and Michael Czank

Mutual exsolution in hornblende and cummingtonite: Compositions, lamellar orientations, and exsolution temperatures 928

Marty Grove and T. Mark Harrison

⁴⁰Ar* diffusion in Fe-rich biotite 940

J. William Carey and David L. Bish

Equilibrium in the clinoptilolite-H₂O system 952

Sukanya Mukhopadhyay and K.T. Jacob

Phase equilibria in the system CaO-CoO-SiO₂ and Gibbs energies of formation of the quaternary oxides CaCoSi₂O₆, Ca₂CoSi₂O₇, and CaCoSiO₄ 963

Svein Stølen, Ronny Glöckner, Fredrik Grønvold, Tooru Atake, and Satoru Izumisawa

Heat capacity and thermodynamic properties of nearly stoichiometric wüstite from 13 to 450 K 973

Kéiko Hattori and Hiroaki Sato

Magma evolution recorded in plagioclase zoning in 1991 Pinatubo eruption products 982

Frank C. Hawthorne, Roberta Oberti, Luciano Ungaretti, and Joel D. Grice

A new hyper-calcic amphibole with Ca at the A site: Fluor-cannilloite from Pargas, Finland 995

P. Ballirano, A. Maras, and P.R. Buseck

Crystal chemistry and IR spectroscopy of Cl- and SO₄-bearing cancrinite-like minerals 1003

NEW MINERAL NAMES 1013

MEMORIAL

Cornelius S. Hurlbut Jr. and James B. Thompson Jr.

Memorial of Harold Williams Fairbairn, 1906--1994 1018

BOOK REVIEW 1020