Chemical composition and evolution of tourmaline-supergroup minerals from the Sb hydrothermal veins in Rožňava area, Western Carpathians, Slovakia

Chemical composition and evolution of tourmaline-supergroup minerals from the Sb hydrothermal... Tourmaline-supergroup minerals are common gangue minerals in Sb-hydrothermal veins on Betliar – Straková, Čučma – Gabriela and Rožňava – Peter-Pavol vein deposits in the Rožňava area, Slovakia. Tourmaline-supergroup minerals form relatively large prismatic to radial aggregates of parallel black to greyish-black crystals. Tourmaline-supergroup minerals from Betliar – Straková and Rožňava – Peter-Pavol are almost homogeneous with intermediate schorl-dravite composition. Čučma – Gabriela tourmaline have distinct zoning with massive core of the schorlitic-to-feruvitic shifting to schorlitic-to-dravitic composition, and dravitic to magnesio-foititic rim. The tourmaline composition is influenced by two main substitutions, namely Ca(Mg,Fe)Na−1Al−1 and X □AlNa−1(Mg,Fe)−1. Betliar – Straková and Rožňava – Peter-Pavol tourmaline-supergroup minerals exhibit only small extents of the X □AlNa−1(Mg,Fe)−1 substitution. This substitution shifts the composition to magnesio-foitite in Čučma – Gabriela tourmaline. The decrease of Al in the core of Čučma – Gabriela tourmaline crystals is caused by extensive Ca(Mg,Fe)Na−1Al−1 substitution. The unit-cell dimensions of all investigated tourmaline-supergroup minerals indicate an octahedral disorder with the Z (Fe3++Mg) proportion calculated from empirical equations varying between 0.85 and 0.87 apfu (atoms per formula unit). Based on Mössbauer spectra, the Z Fe3+ content varied between 0.25 apfu in Betliar – Straková tourmaline and 0.45 apfu in Čučma – Gabriela sample. Based on Fe/(Fe + Mg) ratio, Betliar – Straková tourmaline is slightly enriched in Fe compared to Rožňava – Peter-Pavol, suggesting the impact of the host-rock composition; first are grown in Fe-richer acidic metarhyolitic rocks, latter in metapelites. In Čučma – Gabriela, the variations in Fe/(Fe + Mg) are very likely reflecting the change in fluid composition. Magnesio-foitite is the product of second-stage crystallization forming rims and crack fills. The relatively low Fe3+/Fe2+ ratio suggests only minor proportion of meteoric fluids forming tourmaline. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Mineralogy and Petrology Springer Journals

Chemical composition and evolution of tourmaline-supergroup minerals from the Sb hydrothermal veins in Rožňava area, Western Carpathians, Slovakia

Loading next page...
 
/lp/springer_journal/chemical-composition-and-evolution-of-tourmaline-supergroup-minerals-XXAN0vTZJZ
Publisher
Springer Vienna
Copyright
Copyright © 2017 by Springer-Verlag Wien
Subject
Earth Sciences; Mineralogy; Inorganic Chemistry; Geochemistry
ISSN
0930-0708
eISSN
1438-1168
D.O.I.
10.1007/s00710-017-0507-1
Publisher site
See Article on Publisher Site

References

You’re reading a free preview. Subscribe to read the entire article.


DeepDyve is your
personal research library

It’s your single place to instantly
discover and read the research
that matters to you.

Enjoy affordable access to
over 12 million articles from more than
10,000 peer-reviewed journals.

All for just $49/month

Explore the DeepDyve Library

Unlimited reading

Read as many articles as you need. Full articles with original layout, charts and figures. Read online, from anywhere.

Stay up to date

Keep up with your field with Personalized Recommendations and Follow Journals to get automatic updates.

Organize your research

It’s easy to organize your research with our built-in tools.

Your journals are on DeepDyve

Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.

All the latest content is available, no embargo periods.

See the journals in your area

Monthly Plan

  • Read unlimited articles
  • Personalized recommendations
  • No expiration
  • Print 20 pages per month
  • 20% off on PDF purchases
  • Organize your research
  • Get updates on your journals and topic searches

$49/month

Start Free Trial

14-day Free Trial

Best Deal — 39% off

Annual Plan

  • All the features of the Professional Plan, but for 39% off!
  • Billed annually
  • No expiration
  • For the normal price of 10 articles elsewhere, you get one full year of unlimited access to articles.

$588

$360/year

billed annually
Start Free Trial

14-day Free Trial