The replacement of plagioclase feldspars by albite: Observations from hydrothermal experiments

Oligoclase and labradorite crystals have been experimentally replaced by albite in an aqueous sodium silicate solution at 600°C and 2 kbars. The replacement is pseudomorphic and is characterised by a sharp chemical interface which progresses through the feldspar while preserving the crystallographic...

Full description

Bibliographic Details
Main Authors: Hövelmann, J., Putnis, Andrew, Geisler, T., Schmidt, B., Golla-Schindler, U.
Format: Journal Article
Published: Springer 2010
Online Access:http://hdl.handle.net/20.500.11937/37309
_version_ 1848755010873065472
author Hövelmann, J.
Putnis, Andrew
Geisler, T.
Schmidt, B.
Golla-Schindler, U.
author_facet Hövelmann, J.
Putnis, Andrew
Geisler, T.
Schmidt, B.
Golla-Schindler, U.
author_sort Hövelmann, J.
building Curtin Institutional Repository
collection Online Access
description Oligoclase and labradorite crystals have been experimentally replaced by albite in an aqueous sodium silicate solution at 600°C and 2 kbars. The replacement is pseudomorphic and is characterised by a sharp chemical interface which progresses through the feldspar while preserving the crystallographic orientation. Reaction rims of albite, up to 50 µm thick, can be readily achieved within 14 days. Re-equilibration of plagioclase in an 18O-enriched sodium- and silica-bearing solution results in oxygen isotope redistribution within the feldspar framework structure. The observed characteristics of the reaction products are similar to naturally albitised plagioclase and are indicative of an interface-coupled dissolution- reprecipitation mechanism. Chemical analyses demonstrate that the albitisation is accompanied by the mobilisation of major, minor and trace elements also including elements such as Al and Ti which are commonly regarded as immobile during hydrothermal alteration. The results contribute to developing our understanding of the close association between large-scale albitisation and secondary ore mineralisation which is common in nature. © 2009 Springer-Verlag.
first_indexed 2025-11-14T08:49:31Z
format Journal Article
id curtin-20.500.11937-37309
institution Curtin University Malaysia
institution_category Local University
last_indexed 2025-11-14T08:49:31Z
publishDate 2010
publisher Springer
recordtype eprints
repository_type Digital Repository
spelling curtin-20.500.11937-373092017-09-13T13:38:13Z The replacement of plagioclase feldspars by albite: Observations from hydrothermal experiments Hövelmann, J. Putnis, Andrew Geisler, T. Schmidt, B. Golla-Schindler, U. Oligoclase and labradorite crystals have been experimentally replaced by albite in an aqueous sodium silicate solution at 600°C and 2 kbars. The replacement is pseudomorphic and is characterised by a sharp chemical interface which progresses through the feldspar while preserving the crystallographic orientation. Reaction rims of albite, up to 50 µm thick, can be readily achieved within 14 days. Re-equilibration of plagioclase in an 18O-enriched sodium- and silica-bearing solution results in oxygen isotope redistribution within the feldspar framework structure. The observed characteristics of the reaction products are similar to naturally albitised plagioclase and are indicative of an interface-coupled dissolution- reprecipitation mechanism. Chemical analyses demonstrate that the albitisation is accompanied by the mobilisation of major, minor and trace elements also including elements such as Al and Ti which are commonly regarded as immobile during hydrothermal alteration. The results contribute to developing our understanding of the close association between large-scale albitisation and secondary ore mineralisation which is common in nature. © 2009 Springer-Verlag. 2010 Journal Article http://hdl.handle.net/20.500.11937/37309 10.1007/s00410-009-0415-4 Springer restricted
spellingShingle Hövelmann, J.
Putnis, Andrew
Geisler, T.
Schmidt, B.
Golla-Schindler, U.
The replacement of plagioclase feldspars by albite: Observations from hydrothermal experiments
title The replacement of plagioclase feldspars by albite: Observations from hydrothermal experiments
title_full The replacement of plagioclase feldspars by albite: Observations from hydrothermal experiments
title_fullStr The replacement of plagioclase feldspars by albite: Observations from hydrothermal experiments
title_full_unstemmed The replacement of plagioclase feldspars by albite: Observations from hydrothermal experiments
title_short The replacement of plagioclase feldspars by albite: Observations from hydrothermal experiments
title_sort replacement of plagioclase feldspars by albite: observations from hydrothermal experiments
url http://hdl.handle.net/20.500.11937/37309