American

Mineralogist

1995, Volume 80, March-April, number 3-4

Contents

ARTICLES

Page

201

C. Closmann, Q. Williams: In-situ spectroscopic investigation of high-pressure hydrated (Mg,Fe)SiO3 glasses: OH vibrations as a probe of glass structure

213

Richard J. Harrison, Andrew Putnis: Magnetic properties of the magnetite-spinel solid solution: Saturation magnetization and cation distributions

222

Thomas S. Duffy, Charles Meade, Yingwei Fel, Ho-Kwang Mao, Russell J. Hemley: High-pressure phase transition in brucite, Mg(OH)2

231

Kunal Bose, Jibamitra Ganguly: Quartz-coesite transition revisited: Reversed experimental determination at 500-1200 °ree;C and retrieved thermochemical properties

239

T. P. Hackwell, R. J. Angel: Reversed brackets for the P1=Il transition in anorthite at high pressures and temperatures

247

Hans J. Jakobsen, Niels C. Nielsen, Holger Lindgreen: Sequences of charged sheets in rectorite

253

M. Chiara Domeneghetti, G. Mario Molin, Vittorio Tazzoli: A crystal-chemical model for Pbca orthopyroxene

268

Christina M. B. Line, Andrew Putnis, Christine Putnis, Ciriaco Giampaolo: The dehydration kinetics and microtexture of analcime from two parageneses

280

Guv L. Hovis, Alexandra Navrotsky: Enthalpies of mixing for disordered alkali feldspars at high temperature: A test of regular solution thermodynamic models and a comparison of hydrofluoric acid and leadborate solution calorimetric techniques

285

Laurinda Chamberlin, John R. Beckett, Edward Stolper: Palladium oxide equilibration and the thermodynamic properties of MgAl2O4 spinel

297

K.-U. Hess, D. B. Dingwell, S. L.Webb: The influence of excess alkalis on the viscosity of a haplogranitic melt

305

Yan Bottinga, Pascal Richet, AnneSipp: Viscosity regimes of homogeneous silicate melts

319

Joseph D. Devine, James Le. Gardner, Hans P. Brack, Graham D. Layne,Malcolm J. Rutherford: Comparison of microanalytical methods for estimating H20 contents of silicic volcanic glasses

329

Michael E. Fleet, Yuanming Pan: Site preference of rare earth elements in fluorapatite

336

Roberto V. Santos, Robert N. Clayton: The carbonate content in high-temperature apatite: An analytical method applied to apatite from the Jacupiranga alkaline complex

345

Carolyn Rose Rebbert, Elizabeth Partin, David A. Hewitt: Synthetic biotite oxidation under hydrothermal conditions

355

Erin M. Walling, Peter A. Rock, William H. Casey: The Gibbs energy of formation of huntite, CaMg3(CO3)4, at 298 K and 1 bar from electrochemical cell measurements

361

Frank S. Spear, Matthew J. Kohn, Stephan Paetzold: Petrology of the regional sillimanite zone, west-central New Hampshire, U.S.A., with implications for the development of inverted isograds

377

Daniel Nyfeller, Thomas Armbruster, Roger Dixon, Vladimir Bermanec: Nchwaningite, (Mn2+)2SiO3(OH)2.H2O, a new pyroxene-related chain silicate from the N'chwaning mine, Kalahari manganese field, South Africa

387

Hong Zheng, Sturges W. Bailey: The crystal structure of manandonite-2H2

394

Franklin F. Foit, Jr., Paul D. Robinson, James R. Wilson: The crystal structure of gillulyite, Tl2(As,Sb)8S13,

from the Mercur gold deposit, Tooele County,Utah, U.S.A.

400

Paola Bonazzi, Silvio Menchetti, Giovanni Pratesi: The crystal structure of pararealgar, As4S4

404

New mineral names

MEMORIALS

41O

S. Ross Taylor: Memorial of Louis H. Ahrens, 1918-1990

412

Kenzo Yagi: Memorial of Zyunpei Harada, 1898-1992

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