ISSN

print 2570-7337
online 2570-7345

Supergene minerals from the Nová Anton vein, Hodruša-Hámre, Štiavnické vrchy Mts. (Slovak Republic)


Volume 24, issue 2 (2016), pages 183-193

Keywords

Abstract

An unusually rich occurrence of supergene minerals, represented by azurite, baryte, cerussite, Zn-rich malachite, rosasite, smithsonite and wulfenite was recently identified at the subsurface parts of the Nová Anton epithermal ore vein near Hodruša-Hámre, Štiavnické vrchy Mts., Slovak Republic. Azurite is rare and it forms bright blue crystalline crusts, which consists of thin tabular crystals up to 2 mm. It is associated together with malachite, cerussite and smithsonite. Baryte occurs only infrequently as white, thin tabular crystals up to 5 mm growing on smithsonite. Cerussite is relatively abundant supergene mineral, especially in the proximity of relicts of primary galena. It forms clear to white, well-developed, acicular, prismatic or tabular crystals up to 1.2 cm or massive aggregates and rims up to 3 cm, which are often associated together with malachite and rosasite. Zn-rich malachite is very common supergene mineral at the studied locality and it occurs as pale green to greenish-blue hemispherical or radial aggregates up to 1 cm or crystalline crusts and coatings, which cover areas up to 100 cm2. It is often associated with cerusite or smithsonite with rosasite, rarely also together with wulfenite or azurite. The unit-cell parameters of Zn-rich malachite refined from the powder X-ray diffraction data (for the monoclinic space group P21/a) are: a = 9.459(5) Å, b = 11.979(4) Å, c = 3.219(1) Å, β = 97.84(2)° with V = 361.3(3) Å3. It contain up to 0.18 apfu of Zn. Rosasite is relatively common species. It forms bluish-green to pale blue, hemispherical aggregates up to 7 mm with radial internal structure, which are often grouped to the botryoidal crusts covering areas up to 50 cm2. Rosasite is often associated with smithsonite and Zn-rich malachite. Its refined unit-cell parameters (for the monoclinic space group P21/a) are: a = 12.890(8) Å, b = 9.342(7) Å, c = 3.164(2) Å, β = 110.26(2)° with V = 357.4(4) Å3. Two types of rosasite can by distinguished by chemical composition. Predominant is Zn-rich phase with the Cu/Zn molar ratio in the range of 1.24 - 1.66 (1.11 - 1.25 apfu Cu, 0.75 - 0.89 apfu Zn). Cu-rich rosasite is infrequent and its Cu/Zn molar ratio vary from 3.32 to 3.61 (1.54 - 1.57 apfu Cu, 0.43 - 0.46 apfu Zn). Smithsonite is very common mineral, which is associated mainly with Zn-rich malachite and rosasite. It occurs as white, pale green to pale blue botryoidal crusts, which often consists of rounded rhombohedral or scalenohedral crystals up to 3 mm in size. Except of major Zn, elevated content of Cu (up to 0.08 apfu), and minor contents of Ca (up to 0.02 apfu) and K, Pb, Mg (all up to 0.01 apfu) were detected in smithsonite. Wulfenite is relatively abundant species and it forms orange to yellow, dipyramidal, often hemihedral or tabular crystals up to 1 cm. It was identified by PXRD and its refined unit-cell parameters (for the tetragonal space group I41/a) are: a = 5.438(5) Å, c = 12.1160(7) Å and V = 358.3(3) Å3. Its chemical composition is close to the theoretical end member, PbMoO4. Well-developed supergene zones in-situ, especially with the abudance of supergene Cu and Zn carbonates are not typical for the epithermal ore veins in the Banská Štiavnica ore district. The origin of relatively well developed and rich supergene zone in-situ at the Nová Anton vein is directly linked with the fact, that upper parts of this vein are hosted in limestone.

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References

Anthony J. W., Bideaux R. A., Bladh K. W., Nichols M. C. (2003) Handbook of Mineralogy. Vol. V., Borates, Carbonates, Sulfates. 1-813, Mineral Data Publishing, Tucson.

Behrens M., Girgsdies F. (2010) Structural effects of Cu/Zn substitution in the malachite-rosasite system. Z. Anorg. Allg. Chem. 636, 919-927.

Belokoneva E. L., Gubina Y. K., Forsyth J. B. (2001) The charge density distribution and antiferromagnetic properties of azurite. Phys. Chem. Miner. 28, 498-507.

Bergfest A. (1954) Hodruša I. MS, archív Geofond, Bratislava, 1-105, 58007.

Braithwaite R. S. W., Ryback B. A. (1963) Rosasite, aurichalcite, and associated minerals from Heights of Abraham, Matlock Bath, Derbyshire, with a note on infra-red spectra. Mineral. Mag. 33, 441-449.

Effenberger H., Mereiter K., Zemann J. (1981) Crystal structure refinements of magnesite, calcite, rhodochrosite, siderite, smithsonite, and dolomite, with discussion of some aspects of the stereochemistry of calcite type carbonates. Z. Kristallogr. 156, 233-243

Gavora S., Hromada J., Skavniak M. (1984) Záverečná správa. Hodruša-okolie-vyhľadávací prieskum. Pb, Zn, Cu ruda. Stav k 1. 1. 1984. MS, archív Geofond, Bratislava, 1-193, 59544.

Hill R. J. (1977) A further refinement of barite structure. Can. Mineral. 15, 522-526.

Chevrier G., Giester G., Heger G., Jarosch D., Wildner M., Zemann J. (1992) Neutron single-crystals refinement of cerussite, PbCO3, and comparison with other aragonite-type carbonates. Z. Kristallogr. 199, 67-74.

Kaňa R., Čelko M., Mrákava F. (2011) Hodruša v zemi baníkov. 1-191, Banskoštiavnicko-hodrušský banícky spolok v Banskej Štiavnici, Banská Štiavnica.

Konečný V., Lexa J., Halouzka R., Dublan L., Šimon L., Stolár M., Nagy A., Polák M., Vozár J., Havrila M., Pristaš J. (1998) Geologická mapa Štiavnických vrchov a Pohronského Inovca. GS SR, Bratislava.

Lipold M. V. (1867) Der Bergbau von Schemnitz in Ungarn. Jb. K.-kön. geol. Reichsanst., 17, 317-458.

Laugier J., Bochu B. (2011) LMGP-Suite of Programs for the Interpretation of X-ray Experiments. http://www.ccp14.ac.uk/tutorial/lmgp.

Lugli C., Medici L., Saccardo D. (1999) Natural wulfenite: structural refinement by single-crystal X-ray diffraction. Neues Jb. Miner. Monat., 281-288.

Nickel E. H., Berry L. G. (1981) The new mineral nullaginite and additional data on the related minerals rosasite and glaukosphaerite. Can. Mineral. 19, 315-324.

Onačila F., Rojkovičová Ľ., Jeleň S., Hojstričová V., Štohl J., Lexa J., Žáková E. (1995) Komplexná geologická dokumentácia revíru Banská Štiavnica-Hodruša. MS, archív Geofond, Bratislava,1-63, 82793.

Onačila D., Rojkovičová Ľ., Žáková E., Repčok I., Eliáš K., Kalinaj M. (1993) Epitermálna žilná mineralizácia hodrušského rudného poľa-čiastková záverečná správa. MS, archív Geofond, Bratislava, 78747.

Palache C., Berman H., Frondel C. (1957) The system of mineralogy. 7th edition. Vol. II. John Wiley and sons, Inc. London.

Perchiazzi N. (2006) Crystal structure determination and Rietveld refinement of rosasite and mcguinnessite. Z. Kristallogr. Suppl. 23, 505-510.

Porta P., De Rossi S., Ferraris G., Lo Jacono M., Minelli G., Moretti G. (1988a) Structural characterization of malachite-like coprecipitated precursors of the binary CuO-ZnO catalysts. J. Catal. 109, 367-377.

Porta P., Fierro G., Lo Jacono M., Moretti G. (1988b) Structural characterization of malachite-like coprecipitated precursors of the binary CuO-ZnO catalysts: bulk and surface properties. Catal. Today 2, 675-683.

Pouchou J. L., Pichoir F. (1985) “PAP” (φρZ) procedure for improved quantitative microanalysis. In: Microbeam Analysis (J. T. Armstrong, ed.). San Francisco Press, San Francisco, 104-106.

Sejkora J., Bureš B., Škoda R. (2008) Supergenní Cu-Zn karbonáty z rudního ložiska Horní Rokytnice v Krkonoších. Bull. mineral.-petrolog. Odd. Nár. Muz. (Praha), 16, 1, 17-23.

Sejkora J., Šrein V. (2012) Supergenní Cu mineralizace z Mědníku na Měděnci, Krušné hory (Česká republika). Bull. mineral.-petrolog. Odd. Nár. Muz. (Praha), 20, 2, 255-269.

Števko M. (2015) Nové nálezy minerálov na rudných žilách v Hodruši-Hámroch. Minerál 23, 422-434.

Števko M., Gramblička R., Malíková R. (2015) Nové údaje o supergénnych mineráloch z polymetalického ložiska Čavoj, Strážovské vrchy (Slovenská republika). Bull. mineral.-petrolog. Odd. Nár. Muz. (Praha) 23, 1, 63-74.

Števko M., Malíková R. (2014) Supergénne minerály zo štôlne Juraj, Hodruša-Hámre (Slovenská republika). Bull. mineral.-petrolog. Odd. Nár. Muz. (Praha), 22, 2, 261-268.