Unusual morphological forms of hodrušite from the Rozália vein, Hodruša-Hámre near Banská Štiavnica (Slovak Republic)

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00023272%3A_____%2F15%3A%230002604" target="_blank" >RIV/00023272:_____/15:#0002604 - isvavai.cz</a>

Výsledek na webu

<a href="http://www.jgeosci.org/content/jgeosci.188_sejkora.pdf" target="_blank" >http://www.jgeosci.org/content/jgeosci.188_sejkora.pdf</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.3190/jgeosci.188" target="_blank" >10.3190/jgeosci.188</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Unusual morphological forms of hodrušite from the Rozália vein, Hodruša-Hámre near Banská Štiavnica (Slovak Republic)

Popis výsledku v původním jazyce

Rare Cu-Bi sulphosalt, hodrusite, occurs in the Rozalia vein (levels X-XIV of the Rozalia mine, Hodrusa-Hamre ore deposit near Banska Stiavnica, central Slovakia) in two unusual morphological forms. The first type are brownish bronze thin acicular striated crystals, up to 3 mm long, which are usually grouped into chaotic or irregular aggregates. The second hodrusite type comprises flattened columnar aggregates, up to 1.5 cm long, overgrown by hematite in quartz gangue. These aggregates are distinctly striated with brownish bronze colour and metallic lustre. The earliest columnar aggregates of hodrusite are locally substantially replaced by bismuthinite; these hodrusite-bismuthinite aggregates are further intensively pushed back by hematite displaying W-and Al-rich zones. Acicular crystals of hodrusite in gangue cavities were later than bismuthinite and hematite and their formation was related to remobilisation of Cu and Bi from earlier altered gangue. Powder X-ray diffraction data and chemical composition of both hodrusite types are similar; their unit-cell parameters were refined (monoclinic space group C-2/m) as: a 17.552(5), b 3.905(1), c 27.167(9) angstrom, beta 92.44(3)degrees, V 1860.5(9) angstrom3 (acicular crystals) and a 17.567(2), b 3.9151(7), c 27.155(5) angstrom, beta 92.43(1)degrees, V 1865.9(4) angstrom3 (columnar aggregates). Cu-for-Bi substitution is characteristic of both hodrusite types; it influences calculated N-chem values (0.98-1.33) to the point that it is impossible to distinguish hodrusite (ideal 1.5) from kupcikite (ideal 1.0). The problem is resolved by Fe and Ag contents: kupcikite has more than 2 at. % Fe, cuprobismutite contains more than 2 at. % of Ag; hodrusite usually has Ag and Fe contents below 2 at. %. Hematite is remarkable for its high WO3 content reaching 4.96 wt. % (0.04 apfu), extremely unusual of a hematite from hydrothermal vein mineralization.

Název v anglickém jazyce

Unusual morphological forms of hodrušite from the Rozália vein, Hodruša-Hámre near Banská Štiavnica (Slovak Republic)

Popis výsledku anglicky

Rare Cu-Bi sulphosalt, hodrusite, occurs in the Rozalia vein (levels X-XIV of the Rozalia mine, Hodrusa-Hamre ore deposit near Banska Stiavnica, central Slovakia) in two unusual morphological forms. The first type are brownish bronze thin acicular striated crystals, up to 3 mm long, which are usually grouped into chaotic or irregular aggregates. The second hodrusite type comprises flattened columnar aggregates, up to 1.5 cm long, overgrown by hematite in quartz gangue. These aggregates are distinctly striated with brownish bronze colour and metallic lustre. The earliest columnar aggregates of hodrusite are locally substantially replaced by bismuthinite; these hodrusite-bismuthinite aggregates are further intensively pushed back by hematite displaying W-and Al-rich zones. Acicular crystals of hodrusite in gangue cavities were later than bismuthinite and hematite and their formation was related to remobilisation of Cu and Bi from earlier altered gangue. Powder X-ray diffraction data and chemical composition of both hodrusite types are similar; their unit-cell parameters were refined (monoclinic space group C-2/m) as: a 17.552(5), b 3.905(1), c 27.167(9) angstrom, beta 92.44(3)degrees, V 1860.5(9) angstrom3 (acicular crystals) and a 17.567(2), b 3.9151(7), c 27.155(5) angstrom, beta 92.43(1)degrees, V 1865.9(4) angstrom3 (columnar aggregates). Cu-for-Bi substitution is characteristic of both hodrusite types; it influences calculated N-chem values (0.98-1.33) to the point that it is impossible to distinguish hodrusite (ideal 1.5) from kupcikite (ideal 1.0). The problem is resolved by Fe and Ag contents: kupcikite has more than 2 at. % Fe, cuprobismutite contains more than 2 at. % of Ag; hodrusite usually has Ag and Fe contents below 2 at. %. Hematite is remarkable for its high WO3 content reaching 4.96 wt. % (0.04 apfu), extremely unusual of a hematite from hydrothermal vein mineralization.

Druh

J_x - Nezařazeno - Článek v odborném periodiku (Jimp, Jsc a Jost)

CEP obor

DB - Geologie a mineralogie

OECD FORD obor

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Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2015

Kód důvěrnosti údajů

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

Název periodika

Journal of Geosciences

ISSN

1802-6222

e-ISSN

—

Svazek periodika

60

Číslo periodika v rámci svazku

1

Stát vydavatele periodika

CZ - Česká republika

Počet stran výsledku

12

Strana od-do

11-22

Kód UT WoS článku

000348358700002

EID výsledku v databázi Scopus

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