The rare Hg-sulfosalt, marrucciite, with ideal formula Hg 3 Pb 16 Sb 18 S 46 , was found in the Gelnica ore deposit (Spišsko-Gemerské Rudohorie Mts., Slovak Republic). It occurs as acicular crystals up to 0.5 mm in length and fine-grained aggregates up to 1 mm in quartz (+siderite/dolomite) gangue in association with other sulfosalts (zinkenite, scainiite, boulangerite, chalcostibite, bournonite) and cinnabar. It is opaque, dark steel grey to greyish black, sometimes tarnished to a bronze-brown tint, has a dark grey streak with a very weak reddish tint and a metallic luster. Marrucciite is very brittle but thin acicular crystals are flexible. One good cleavage parallel to the elongation of the crystals was observed. The VHN 20g microhardness is 85 (69-101) kp/mm 2 and corresponds to a Moh's hardness of c. 2; the calculated density is 6.00 g.cm . In reflected light, marrucciite is white to greyish white with a weak yellowish tint, distinct bireflectance and white-white grey pleochroism. Under crossed polars, it has distinct anisotropy, with rotation tints in shades of grayish brown and dark brown. Dark red internal reflections were observed only rarely. Marrucciite is monoclinic, space group C2/m with a 48.12 (1)

Unusual high-to low-T sulphide mineralization with Ni-(Bi, Ag) phases was examined at the NYF intragranitic pegmatite No. III from Vepice near Kovářov enclosed in the Milevsko Pluton, Moldanubian Zone, Southern Bohemia. Zoned pegmatite dike, up to 30 cm thick, has transitional contact with host durbachite and its internal structure includes transitional unit, border granitic unit, graphic unit, blocky unit (Kfs+Qz), quartz core and small miarolitic pocket. Sulphide mineralization locally associated with calcite and fluorite is represented by common pyrite with minor galena, accessory chalcopyrite, sphalerite, marcasite, native Bi and Ni-(Bi, Ag) minerals -argentopentlandite, parkerite and pentlandite. It is developed in small miarolitic pockets and on pegmatite fractures cutting all pegmatite units. Irregular anhedral grains and aggregates of argentopentlandite, < 200 μm in size, associated with chalcopyrite, have empirical formula Ag 0.97 (Fe 4.88 Ni 3.10 Cu 0.04 Co 0.01 ) Σ8.03 (S 7.96 As 0.03 ) Σ7.99 . Zoned irregular aggregates of parkerite, 20-30 μm in size, are typically associated with pentlandite, or overgrow galena and yield empirical formula (Ni 3.02 Fe 0.02 Co 0.01 ) Σ3.06 (Bi 1.73 Sb 0.05 As 0.04 ) Σ1.92 S 2.02 . Pentlandite is present in two morphological forms: rare lenticular to isometric anhedral grains, ≤ ~200 μm in size, and numerous small tabular crystals, ≤ 20 μm in length, in subparallel arrangement rimming aggregates of other sulphides. Empirical formula is (Ni 4.57 Fe 4.14 Co 0.25 ) Σ8.96 (S 8.01 As 0.02 ) Σ8.03 . Evaluation of relative chronology of the sulphide minerals is complicated mainly due to complex textural relations. Pyrite + marcasite are likely pseudomorphs after pyrrhotite as the earliest phase whereas pentlandite and native Bi are among the latest. Early sulphides (pyrrhotite, chalcopyrite, sphalerite, argentopentlandite) crystallized at T < ~550-400 °C, whereas pyrite, marcasite, galena, parkerite, and native Bi at T < 240 °C. Cooling of the system below T ~200 °C appeared soon after transformation of pyrrhotite to pyrite+marcasite aggregates. Sulphides manifest that concentrations of Ni in residual pegmatite melt and exsolved fluids were high enough to facilitate saturation of Ni-sulphides. Very high Ni/Co ratio in sulphides reflects a much lower concentration of cobalt in durbachite. The examined Ni-(Bi, Ag) sulphides manifest that high concentrations of highly compatible Ni in parental granite may be reflected in accessory minerals from its pegmatite.

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X-ray powder diffraction data, unit-cell parameters and space group for a rare natural organic mineral refikite, C 20 H 32 O 2 , abiet-13(15)-en-18-oic acid, are reported [a = 22.55(2) Å, b = 10.469(6) Å, c = 7.930(9) Å, unit-cell volume V = 1871.82 Å 3 , Z = 4 and space group P2 1 2 1 2]. All measured lines were indexed and are consistent with the P2 1 2 1 2 space group. No detectable impurities were observed.

Dobšináite, ideally Ca 2 Ca(AsO 4 ) 2 •2H 2 O, is a new supergene mineral from the Dobšiná deposit, Slovak Republic, associated with phaunouxite, picropharmacolite, erythrite-hörnesite, gypsum and aragonite. It forms white to pink clusters or polycrystalline aggregates up to 1-4 mm in size consisting of densely intergrown, slightly rounded thin tabular to platy crystals up to 0.1 mm in size. Dobšináite has a white streak, vitreous luster, does not fluoresce under either short-or long-wave ultraviolet light. Cleavage on {010} is good, the Mohs hardness is ~3, and dobšináite is brittle with an uneven fracture. The calculated density is 3.395 g/cm 3 . Dobšináite is optically biaxial negative, the indices of refraction are α´ = 1.601(2) and γ´ = 1.629(2) and 2V meas. is 60° (+/-20°). Dobšináite is monoclinic, space group P2 1 /c, a = 5.990( 2), b = 13.013(4), c = 5.726(2) Å, β = 108.47(3)°, V = 423.3(3) Å 3 , Z = 2. The seven strongest lines in the X-ray powder diffraction pattern are as follows: d (Å)/I(hkl): 5.197/37(110); 3.443/38(130); 3.385/66(031); 3.249/77(040); 3.201/42(13-1); 3.026/100(121) and 2.822/60(10-2). The chemical analyses by electron microprobe yielded (in wt. %) CaO 36.74, MgO 0.89, NiO 0.37, CoO 0.51, P 2 O 5 0.03, As 2 O 5 52.75, SO 3 0.18, H 2 O calc. 8.31, total 99.78. The resulting empirical formula on the basis of 10 O atoms per formula unit is Ca 2 (Ca 0.84 Mg 0.10 Co 0.03 Ni 0.02 ) Σ0.99 [(AsO 4 ) 1.99 (SO 4 ) 0.01 ] Σ2.00 •2H 2 O. Dobšináite is the Ca-dominant member of the roselite group as confirmed by stoichiometry, X-ray powder diffraction data and Raman spectroscopy. It is named after its type locality Dobšiná, Slovak Republic. Dobšináite was formed during weathering of primary Co and As-bearing ore minerals (safflorite, arsenopyrite) in a Ca enriched environment under relatively dry conditions.