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In this contribution, we studied mineralogy of a small, long abandoned ore occurrence near the village of Hiadel' in the Nízke Tatry Mts. (Slovakia). An earlier mineral association consists of pyrite I, arsenopyrite, rutile, apatite, monazite, and possibly zircon. This association is located in alteration zones with abundant sheet silicates. Carbonates are found in this association but also in the milky quartz that contains no sheet silicates. The composition of the carbonates is variable; they belong to the siderite-magnesite and dolomite-ankerite solid solution, rarely to calcite. Later ore minerals are represented by stibnite, Pb-Sb sulfosalts (zinkenite, jamesonite, or robinsonite), tetrahedrite, chalcostibite, bournonite, and pyrite II. The temporal relationship among these minerals cannot be determined from our samples. Tetrahedrite is Zn-rich and Ag-poor. From a mineralogical point of view, this occurrence does not deviate from other ore deposits and occurrences known in the Tatric part of the Nízke Tatry Mts. [ABSTRACT FROM AUTHOR]

A very rare mineral gilmarite, triclinic Cu3(AsO4)(OH)3 mineral phase dimorphous with clinoclase, was found in an old abandoned Jirásek granodiorite quarry in Běloves near Náchod, East Bohemia. This is the first occurrence of this mineral in the Czech Republic. Gilmarite occurs there as greenish blue flattened and elongated crystals forming rosettes and crystalline aggregates up to 1 mm in size in association with malachite, olivenite, cuprite and bluish green copper silicate (chrysocolla). Gilmarite is triclinic, space group P1, the unit-cell parameters refined from X-ray powder diffraction data are: a 5.449(2), b 5.870(4), c 5.109(3)Å, α 115.00(3)˚, β 93.09(5)˚, γ 91.83(5)˚ and V 147.6(1) Å3. Chemical analyses of gilmarite correspond to the empirical formula (Cu)2.99[(AsO4)0.98 (PO4)0.01]Σ0.99(OH)2.98 on the basis of As+P+Si+V = 1 apfu. [ABSTRACT FROM AUTHOR]

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(with)° 2 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) ų. 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) ų. 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. [ABSTRACT FROM AUTHOR]

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An interesting association of supergene minerals represented by anglesite, aragonite, brianyoungite, cerussite, gypsum, hemimorphite, malachite, mimetite, pyromorphite and wulfenite was found at the Čavoj base metal deposit, Strážovské vrchy Mts., Slovak Republic. Brianyoungite occurs as white crystalline coatings and irregular to spherical aggregates, which consist of thin-tabular crystals up to 0.1 mm in size. It was found together with aragonite and gypsum on the surface of ore fragments at the dumps of Geschenk and Ferdinand shaft. The refined unit-cell parameters of brianyoungite from the powder X-ray data are: a 15.710(8) Å, b 6.273(7) Å, c 5.45(1) Å, V = 537(1) Å3. Cerussite is the most abundant supergene phase. It forms well developed colourless to white tabular or prismatic crystals up to 5 mm in size, associated together with anglesite, mimetite, pyromorphite and wulfenite. Its refined unit-cell parameters are: a 5.189(1) Å, b 8.507(2) Å, c 6.152(1) Å, V 271.56(9) Å3. Hemimorphite was identified at the dumps situated near Strieborná adit as white hemispherical crystalline aggregates up to 2 mm in the fissures of sphalerite-rich gangue. It is orthorhombic, space group Imm2 and the unit-cell parameters refined from X-ray powder diffraction data are: a 8.3634(8) Å, b 10.711(1) Å, c 5.1134(5) Å, and V 458.07(8) Å3. Mimetite is rare mineral and it occurs only at the Baniská area. It forms bright yellow to yellowish-green crystalline aggregates and crusts, which are composed by prismatic crystals up to 1 mm in size. Its unit-cell parameters refined from powder X-ray data are: a 10.236(10) Å, c 7.4126(9) Å and V 673(1) Å3. Mimetite from the Čavoj deposit contain only minor amounts of Ca (up to 0.33 apfu) and P (up to 0.39 apfu) with the empirical formula (average of 6 point analyses) corresponding to (Pb5.11Ca0.21)Σ5.32 [(AsO4) 2.77 (PO4) 0.23]Σ3.00Cl1.17 on the basis of P+As+V+Si+S=3 apfu. Pyromorphite was identified in several samples from the Ferdinand shaft dump as pale-green to pale-yellow prismatic crystals up to 2 mm in size, which are often grouped to the crystalline crusts and aggregates together with cerussite and wulfenite. The refined unit-cell parameters of pyromorphite are: a 9.986(8) Å, c 7.3528(3) Å and V 635.0(5) Å3. Only minor amounts of Ca (up to 0.19 apfu) and As (0.07 apfu) were detected in studied samples of pyromorphite and its empirical formula (average of 9 point analyses) is corresponding to (Pb4.97Ca0.10)Σ5.07 [(PO4) 2.95 (AsO4) 0.05]Σ3.00Cl1.15 on the basis of P+As+V+Si+S=3 apfu. Wulfenite is rare supergene phase at the studied locality (dump of Ferdinand shaft) and it occurs as well developed, orange pyramidal crystals up to 1 mm in size together with cerussite and pyromorphite. It is tetragonal, space group I41/a and its unit-cell parameters refined from X-ray powder diffraction data are: a 5.435(1) Å, c 12.1065(2) Å and V 357.59(9) Å3. Its chemical composition is close to the end member formula with only insignificant amounts of P and As (both up to 0.01 apfu) and empirical formula (average of 5 point analyses) corresponding to Pb1.00 [(MoO4) 0.98 (AsO4) 0.01 (PO4) 0.01]Σ1.00 on the basis of Mo+W+As+P=1 apfu. On the basis of detailed paragenetic study two principal associations of supergene minerals were distinguished at the Čavoj deposit: a) supergene phases (e.g. cerussite, hemimorphite, mimetite, pyromorphite or wulfenite) formed by in-situ decomposition of primary ore minerals in the supergene zone or b) supergene minerals of sub-recent origin, which were formed by the weathering of ore fragments in dump environment (e.g. aragonite, brianyoungite and gypsum). [ABSTRACT FROM AUTHOR]

The body of Mg skarn from Včelín - south near Hodruša-Hámre village (Slovak Republic) is developed at the con- tact of Neogene granodiorite with the Middle to Upper Triassic dolomitic limestone. Except of carbonates (dolomite, calcite) the most common minerals of Mg skarn, which were formed during the prograde stage are forsterite and spinel (Fe2+ 0.06 - 0.12 apfu and Fe3+ 0.10 - 0.28 apfu). Forsterite was initially present as euhedral crystals up to 3 cm, but later was significantly replaced by clinochlore and antigorite during the retrograde stage. Forsterite occurs only as microscopic relics compositionally close to the end-member formula. Spinel is a common mineral occurring as well-developed black octahedral crystals up to 1.5 cm long. Magnetite forms as fine-grained masses or euhedral crystals up to 1 cm in size. It shows elevated contents of Mg (up to 0.31 apfu) and Al (up to 0.16 apfu) and was most probably formed at retrograde stage of the Mg skarn evolution. [ABSTRACT FROM AUTHOR]

Hausmannite and manganosite were identified at the Čierna baňa manganese deposit near Čučma, Slovenské rudohorie Mts., Gemeric Superunit, Slovak Republic. Hausmannite occurs as black, fine-grained masses up to 10 cm in size. It contain aggregates of manganosite and microscopic barite, rhodonite, rhodochrosite and spessartine inclusi- ons. The refined unit-cell parameters of hausmannite from the powder X-ray diffraction data (for the tetragonal space group I4 /amd) are a = 5.786(11), c = 9.411(2) Å with V = 315.1(6) Å3. Manganosite forms anhedral, emerald to dark green grains and aggregates up to 2 mm in size embedded in hausmannite matrix. It is first documented occurrence of this specie in Slovakia. The refined unit-cell parameters of manganosite from the powder X-ray diffraction data (for the cubic space group Fm3m) are a = 4.445(1) Å with V = 87.801(2) Å3. Its chemical composition is close to the end member with the empirical formula (average of 6 point analyses) corresponding to (Mn0.99Mg0.01)Σ1.00O1.00 on the basis of O = 1. [ABSTRACT FROM AUTHOR]

Bismuth tellurides (tetradymite and tellurobismuthite) were identified in the heavy mineral fraction of alluvial placers from Pukanský potok brook near Pukanec, Štiavnické vrchy Mountains, Slovak Republic. They forms only very slightly rounded aggregates up to 5 mm in size with typical perfect cleavage. Aggregates of bismuth tellurides from Pukanec are mostly represented by tetradymite, which has an uniform chemical composition and only minor contents of Se (up to 0.10 apfu) and Sb (0.01 apfu) were detected. Its empirical formula is (Bi2.00Sb0.01)Σ2.01Te1.99(S0.92Se0.08) Σ 1.00 on basis of 5 apfu. Tellurobismuthite was observed as microscopic oval or irregular elongated inclusions in tetradymite. Only rarely aggregates of tellurobismuthite up to 3 mm in size with thin tetradymite rim were observed. The chemical composition of tellurobismuthite is nearly close to the end member, it has only minor contents of Se (0.02 apfu) and Sb (0.02 apfu) and its empirical formula is (Bi2.01Sb0.02)Σ2.03(Te2.96Se0.01)Σ2.97 on basis of 5 apfu. This find of bismuth tellurides indicates the existence of previously unknown primary Bi-Te mineralization near Pukanec, but its connection to the epithermal Au-Ag mineralization is not clear. [ABSTRACT FROM AUTHOR]

The minerals of the tetrahedrite isotypic series are the main ore phases at the Piesky deposit and in the past they were the most important source of copper and silver at the whole Špania Dolina ore district (central Slovakia, Slovak Republic). They occur as veinlets, impregnations or massive aggregates up to 10 cm in size, which are associated together with chalcopyrite in quartz-carbonate veins or in mineralized rocks and are often altered to the yellowish-green aggregates of amorphous Cu-Sb-Fe phases or diverse supergene minerals. The chemical composition of minerals of the tetrahedrite isotypic series from the various parts of the Piesky deposit is rather uniform. In the trigonal site Cu is dominant element and only low content of Ag (up to 0.04 apfu) was detected. The overall content of divalent metals like Fe, Zn as well as slight amount of Pb in the tetrahedral site is up to 1.3 - 1.7 apfu, which together with elevated content of Cu (higher than theoretical value of 10 apfu) suggest the presence of at least some Cu2+ in this possition. In the X possition Sb is the prevalent element, so As-rich tetrahedrite is the absolutely dominant species at the Piesky deposit. Only in one case, Sb-rich tennantite as an irregular zones up to 50 μm in size was observed in the As-rich tetrahedrite. Characteristic feature of tetrahedrite-tennantite minerals from the Piesky deposit is regular content of Bi (up to 0.14 apfu). [ABSTRACT FROM AUTHOR]

Native bismuth forms rare aggregates (up to 1 mm across) in quartz core of the beryl-type granitic pegmatite from Bratislava, Švábsky Hill (Malé Karpaty Mts., Slovakia). The pegmatite dike (<1 m thickness) cuts parental Hercynian S-type granites of the Bratislava massif. The bismuth shows homogeneous, nearly end-member composition (only 0.2 wt.% Sb). It is partly replaced by bismite and bismutite along the rims. Native bismuth precipitated during inal hydrothermal stage of the pegmatite crystallization at temperature 250 - 260 °C, whereas supergene bismite and bismutite are products of late oxidation and weathering processes, or low-temperature alteration of the bismuth. [ABSTRACT FROM AUTHOR]

Pilsenite, ideally Bi4Te3 was found in the body of hydrothermal metasomatites, which is located near Poruba pod Vihoraltom, Vihoralt Mts., Slovak Republic. It forms lead-grey, subhedral grains up to 7 mm in size with typical perfect cleavage. Pilsenite grains are often grouped into the aggregates and clusters up to 3 x 2 cm, which are embedded in brownish metasomatite. Its refined unit-cell parameters from the powder X-ray diffraction data (for the trigonal space group R-3m) are a = 4.430(4), c = 41.834(3) Å with V = 710.971(1) ų. The chemical composition of pilsenite is close to the end member and apart from Bi and Te only minor contents of Pb (up to 0.06 apfu), Se (up to 0.03 apfu) and S (up to 0.03 apfu) were detected. Its average empirical formula is (Bi3.95Pb0.05)Σ4.00(Te2.96Se0.02S0.02)Σ3.00 on the basis of 7 apfu. [ABSTRACT FROM AUTHOR]