 | | Journal (article/letter/editorial) | | 809-819 (2010) DOI : 10.3749/canmin.48.4.809 ÅKERMANITE BREAKDOWN TO A CUSPIDINE-BEARING SYMPLECTITE...symplectitic intergrowth formed from the breakdown of åkermanite (XMg = 0.97, Na-mel12Gh3) in a calc-silicate...approximately matches the composition of the adjacent åkermanite, with the exception of Na and Fe, which were...were probably mobile (or retained in residual åkermanite in the case of Na). The dominant phases in the intergrowth...probably resulted from progress of the reaction: åkermanite + F = diopside + cuspidine + monticellite, with |  | | Journal (article/letter/editorial) | | monticellite + spinel, and one also contains åkermanite. Reaction zones are dominated by diopside and...display extreme zoning in Si, Al, Ti, and XMg. Åkermanite contains up to 1.5 wt% Na2O. Textures in the...intergrowths of diopside, forsterite, and monticellite. Åkermanite and forsterite are separated locally by a coarse...contact metamorphic environments. In this paper, new observations and data are reported on calc-silicate...+ forsterite + monticellite, with additional åkermanite in one case. Such assemblages represent the very |  | | Journal (article/letter/editorial) | | rate in diopsides from the Adirondack Mountains, New York ELIZABETH A. JOHNSON,1,* GEORGE R. ROSSMAN,1 M...marble samples from the Adirondack Mountains, New York, using FTIR spectroscopy. Single-crystal polarized...the spectra of diopside from a xenolith at Cascade Slide. Total OH content in the diopsides ranges from...peak metamorphism (~750 °C, 7–8 kbar). The Cascade Slide diopsides have an Fe3+/Fe2+ of 0.98, compared...in the Mount Marcy anorthosite massif at the Cascade Slide. Diopside grains from each sample were separated |  | | Journal (article/letter/editorial) | | calcite (±kirschsteinite, glaucochroite, aegirine, åkermanite, plombierite-tobermorite group, hydromagnesite...defined as the new mineral species manganvesuvianite and Britvin et al. (2003) defined a new fluorvesuvianite...in association with clintonite-monticellite (± åkermanite ± wollastonite) is also not uncommon (Larsen...replacing OH on the W sites. Notice that recently a new fluorvesuvianite end-member has been defined (Britvin...se assemblages in contact skarns of the Clark Mountain Thrust, N.E. San Bernardino Co., Calif. Abstracts |  | | Report (issue) | | George Washington University Washington, D.C. 20052 USA Louise Corriveau Geological Survey of Canada GSC-Québec...Geosciences Skidmore College Saratoga Springs, New York 12866 USA Mervin J. Bartholomew Department of Earth...Tennessee 38152 USA Memoir 197 3300 Penrose Place, P.O. Box 9140 ■Boulder, Colorado 80301-9140, USA 2004 MWR197...Place, P.O. Box 9140, Boulder, Colorado 80301-9140, USA. Copyright is not claimed on any material prepared...Place, P.O. Box 9140, Boulder, Colorado 80301-9140, USA www.geosociety.org Printed in U.S.A. GSA Books Science |
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