Next Article in Journal
The Sierra de Cacheuta Vein-Type Se Mineralization, Mendoza Province, Argentina
Previous Article in Journal
Removal of Potassium and Iron in Low Grade Bauxite by a Calcination-Acid Leaching Process
Article Menu
Issue 4 (April) cover image

Export Article

Open AccessArticle
Minerals 2018, 8(4), 126; doi:10.3390/min8040126

Towards Zn-Dominant Tourmaline: A Case of Zn-Rich Fluor-Elbaite and Elbaite from the Julianna System at Piława Górna, Lower Silesia, SW Poland

1
Department of Mineralogy, Petrography and Geochemistry, AGH University of Science and Technology, Mickiewicza 30, 30-059 Kraków, Poland
2
Faculty of Materials Science and Ceramics, AGH University of Science and Technology, Mickiewicza 30, 30-059 Kraków, Poland
3
Faculty of Earth Sciences, University of Silesia in Katowice, Będzińska 60, 41-200 Sosnowiec, Poland
4
Institute of Geological Sciences, University of Wrocław, pl. M. Borna 9, 50-204 Wrocław, Poland
*
Author to whom correspondence should be addressed.
Received: 18 January 2018 / Revised: 16 March 2018 / Accepted: 16 March 2018 / Published: 22 March 2018
View Full-Text   |   Download PDF [45588 KB, uploaded 30 March 2018]   |  

Abstract

Tourmalines are a group of minerals which may concentrate various accessory components, e.g., Cu, Ni, Zn, Bi, Ti, and Sn. The paper presents fluor-elbaite and elbaite from a dyke of the Julianna pegmatitic system at Piława Górna, at the NE margin of the Bohemian Massif, SW Poland, containing up to 6.32 and 7.37 wt % ZnO, respectively. Such high amounts of ZnO are almost two times higher than in the second most Zn-enriched tourmaline known to date. The compositions of the Zn-rich tourmalines from Piława Górna, studied by electron micropropy and Raman spectroscopy, correspond to the formulae: X(Na0.733Ca0.0130.254)Σ1Y(Al1.033Li0.792Zn0.755Fe2+0.326Mn0.094)Σ3ZAl6(TSi6O18)(BO3)3V(OH)3W(F0.654OH0.344), and X(Na0.779Ca0.0150.206)Σ1Y(Al1.061Li0.869Zn0.880Fe2+0.098Mn0.094)Σ3ZAl6(TSi6O18)(BO3)3V(OH)3W(OH0.837F0.163), respectively, with Zn as one of the main octahedral occupants. A comparison with other tourmalines and associated Zn-rich fluor-elbaite and elbaite from the pegmatite indicates that atypically high Zn-enrichment is not a result of Zn-Fe fractionation, but dissolution and reprecipitation induced by a late (Na,Li,B,F)-bearing fluid within the assemblage of gahnite spinel and primary schorl-type tourmaline. This strongly suggests Na-Li-B-F metasomatism of gahnite-bearing mineral assemblages as that is the only environment that can promote crystallization of a hypothetical Zn-dominant tourmaline. The compositions of the Zn-rich fluor-elbaite and elbaite suggest three possible end-members for such a hypothetical tourmaline species: NaZn3Al6(Si6O18)(BO3)3(OH)3(OH), ☐(Zn2Al)Al6(Si6O18)(BO3)3(OH)3(OH) and Na(Zn2Al)Al6(Si6O18)(BO3)3(OH)3O by analogy with other tourmalines with divalent Y occupants, such as schorl/foitite/oxy-schorl and dravite/magnesio-foitite/oxy-dravite. View Full-Text
Keywords: tourmaline; fluor-elbaite; elbaite; Zn-enrichment; electron microprobe; Raman spectroscopy; granitic pegmatites; Piława Górna; Sudetes tourmaline; fluor-elbaite; elbaite; Zn-enrichment; electron microprobe; Raman spectroscopy; granitic pegmatites; Piława Górna; Sudetes
Figures

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. (CC BY 4.0).

Share & Cite This Article

MDPI and ACS Style

Pieczka, A.; Gołębiowska, B.; Jeleń, P.; Włodek, A.; Szełęg, E.; Szuszkiewicz, A. Towards Zn-Dominant Tourmaline: A Case of Zn-Rich Fluor-Elbaite and Elbaite from the Julianna System at Piława Górna, Lower Silesia, SW Poland. Minerals 2018, 8, 126.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics

1

Comments

[Return to top]
Minerals EISSN 2075-163X Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top