Paragenesis, composition and origin of Ba- and Ca-rich stronalsite, a rare strontium tectosilicate, in rocks of the teschenite association, Silesian Unit, Western Carpathians, Czech Republic

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61989592%3A15310%2F25%3A73633674" target="_blank" >RIV/61989592:15310/25:73633674 - isvavai.cz</a>

Result on the web

<a href="https://www.cambridge.org/core/journals/mineralogical-magazine/article/paragenesis-composition-and-origin-of-ba-and-carich-stronalsite-a-rare-strontium-tectosilicate-in-rocks-of-the-teschenite-association-silesian-unit-western-carpathians-czech-republic/C71FA506C847C107AC37ED99FCBDACFB" target="_blank" >https://www.cambridge.org/core/journals/mineralogical-magazine/article/paragenesis-composition-and-origin-of-ba-and-carich-stronalsite-a-rare-strontium-tectosilicate-in-rocks-of-the-teschenite-association-silesian-unit-western-carpathians-czech-republic/C71FA506C847C107AC37ED99FCBDACFB</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1180/mgm.2024.97" target="_blank" >10.1180/mgm.2024.97</a>

Result language

angličtina

Original language name

Paragenesis, composition and origin of Ba- and Ca-rich stronalsite, a rare strontium tectosilicate, in rocks of the teschenite association, Silesian Unit, Western Carpathians, Czech Republic

Original language description

Barium- and Ca-rich stronalsite [ideally SrNa2Al4Si4O16] occurs rarely as pseudomorphs, which are probably after nepheline, and is found in hydrothermally altered Sr-enriched leucocratic dykes or streaks hosted by mesocratic amphibole–pyroxene teschenite in the Silesian Unit (Flysch Belt of the Western Carpathians, Czech Republic). In addition to stronalsite, the pseudomorphs consist of slawsonite, celsian, biotite, muscovite, alkali feldspar, natrolite and thomsonite-Ca. The surrounding groundmass is rich in alkali feldspars and zeolites and sporadically also contains amphibole phenocrysts, chloritised biotite, fluorapatite and other accessory and/or secondary minerals. Both compositional types of stronalsite have identical Raman spectra. The Ba-rich stronalsite contains 0.55–0.83 apfu Sr, 0.12–0.37 apfu Ba, and &lt;0.08 apfu Ca. In contrast, Ca-rich stronalsite contains 0.65–0.82 apfu Sr, 0.10–0.23 apfu Ca, and &lt;0.06 apfu Ba. The substitution mechanisms by which Ca enters the structure of stronalsite could not be satisfactorily clarified from the available data; the best stoichiometric fit suggests for substitution of Sr, which should not be possible due to the different crystal structure of the Ca-analogue of stronalsite, lisetite [ideally CaNa2Al4Si4O16]. The Na contents range is 1.82–2.42 apfu and the K contents are consistently low (&lt;0.09 apfu). The T site contains 3.91–4.26 apfu Si, 3.76–4.00 apfu Al and 0.00–0.11 apfu Fe3+. The main source of Sr was probably primary magmatic plagioclase that underwent hydrothermal alteration by post-magmatic high-temperature brines mixed with fluids of external origin. On the basis of previous research and paragenetic relationships, we estimate that stronalsite crystallised at T ∼250–320°C and P &lt;100 MPa.

Czech name

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Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

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OECD FORD branch

10505 - Geology

Project

—

Continuities

S - Specificky vyzkum na vysokych skolach

Publication year

2025

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

MINERALOGICAL MAGAZINE

ISSN

0026-461X

e-ISSN

1471-8022

Volume of the periodical

89

Issue of the periodical within the volume

3

Country of publishing house

GB - UNITED KINGDOM

Number of pages

13

Pages from-to

"357–369"

UT code for WoS article

001554146100001

EID of the result in the Scopus database

2-s2.0-85213895981