Nesquehonite from the Pezinok-Kolársky vrch antimony deposit, Malé Karpaty Mts. (Slovak Republic)
Keywords
Abstract
An uncommon post-mining mineral assemblage with nesquehonite, Sr-rich brandholzite and hörnesite was recently discovered at the Kolársky vrch antimony deposit near Pezinok, Malé Karpaty Mts., Slovakia. Nesquehonite occurs as white opaque pseudomorphs after pre-existing flattened crystals and crystalline aggregates of lansfordite up to 18 mm in size associated with aragonite, gypsum, brandholzite and hörnesite. Its refined unit-cell parameters (for the monoclinic space group P21/n) are: a 7.694(1) Å, b 5.364(1) Å, c 12.118(2) Å, β 90.33(2)° and V 500.2(1) Å3. Except of dominant content of Mg only minor amounts of Si were detected in studied nesquehonite. Sr-rich brandholzite occurs as colourless, well developed, tabular pseudohexagonal crystals up to 3 mm in size and its empirical formula based on (Sb+As = 2 apfu) is (Mg0.72Sr0.21)Σ0.93(Sb1.95As0.05)Σ2.00(OH)12·6H2O. Hörnesite forms microscopic spherical aggregates up to 70 μm enclosed in nesquehonite. It has near end-member composition with empirical formula (Mg3.24Fe0.01)Σ3.25(AsO4)1.93(SiO4)0.04(SO4)0.03·8H2O (based on As+Si+S = 2 apfu). The whole supergene assemblage is a product of post-mining weathering of stibnite and arsenopyrite in carbonate (dolomite) rich environment under near-neutral conditions.
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References
Andráš P, Kotulová J, Hašková A, Luptáková J (2002) Origin and evolution of ore-forming fluids at Pezinok-Kolársky Vrch Sb deposit (Western Carpathians, Slovakia). Slovak Geol Mag 8(2): 159-169
Burnham Ch W (1962) Lattice constant refinement. Carnegie Inst Washington Year Book 61: 132-135
Cambel B (1959) Hydrothermal deposits in the Malé Karpaty Mts., mineralogy and geochemistry of ores. Acta Geol Geograph Univ Comen, Geol 3, 1-348 (in Slovak)
Cambel B, Khun M (1983) Geochemical characteristics of black shales from ore-bearing complex of the Malé Karpaty Mts. Geol Zbor Geol Carpath 34(3): 359-382
Campostrini I (2001) Le Miniere di Brosso. 1-185, Monografie XXIX, Museo Regionale di Scienze Naturali, Torino, Italy
Chovan M, Háber M, Jeleň S, Rojkovič I (1994) Ore textures in the Western Carpathians. 1-219, Slovak Academic Press, Bratislava
Chovan M, Rojkovič I, Andráš P, Hanas P (1992) Ore mineralization of the Malé Karpaty Mts. (Western Carpathians). Geol Carpath 43(5): 275-286
Fenoglio M (1935) Ricerche sulla nesquehonite delle miniere di Cogne in Val d´Aosta. Periodico di Mineralogia 6(1): 1-17
Fischbeck R, Müller G (1971) Monohydrocalcite, hydromagnesite, nesquehonite, dolomite, aragonite, and calcite speleothems of the Fränkische Sweiz, Western Germany. Contrib Mineral Petr 33(2): 87-92
Friedrich A, Wildner M, Tillmanns E, Merz PL (2000) Crystal chemistry of the new mineral brandholzite, Mg(H2O)6[Sb(OH)6]2, and of the synthetic analo- gues M2+(H2O)6[Sb(OH)6]2 (M2+= Mg, Co). Am Mineral 85(3-4): 593-599
Genth FA, Penfield SL (1890) On Lansfordite, Nesquehonite, a new Mineral, and Pseudomorphs of Nesquehonite after Lansfordite. Am J Sci 39: 121-137
Giester G, Lengauer CL, Rieck B (2000) The crystal structure of nesquehonite, MgCO3·3H2O, from Lavrion, Greece. Miner Petrol 70(3-4): 153-163
Ivan P, Méres Š, Putiš M, Kohút M (2001) Early Paleozoic metabasalts and metasedimentary rocks from the Malé Karpaty Mts. (Western Carpathians): Evidence for Early Paleozoic riftogenous basin and oceanic crust. Geol Carpath 52(2): 67-78
Kinsolving MR, MacGillavry C, Pepinsky R (1950) Twinning in nesquehonite, MgCO3·3H2O. Am Mineral 35(1-2): 127
Majzlan J, Števko M, Lánczoš T (2016) Soluble secondary minerals of antimony in Pezinok and Kremnica (Slovakia) and the question of mobility or immobility of antimony in mine waters. Environ Chem 13(6): 927-935
Martini I, Kavalieris J (1978) Mineralogy of the Transvaal caves. S Afr J Geol 81(1): 47-54
Meixner H (1950) Neue Mineralvorkommen aus den Ostalpen. Heidelberger Beiträge zur Mineralogie und Petrographie 2(3): 195-209
Ondruš P (1993) ZDS - A computer program for analysis of X-ray powder diffraction patterns. Materials Science Forum, 133-136, 297-300, EPDIC-2. Enchede
Pepinsky R (1941) Twinning in nesquehonite, MgCO3 ·3H2O. Phys Rev (59): 926-926
Pouchou J, Pichoir F (1985) „PAP“ (jrZ) procedure for improved quantitative microanalysis. In: Armstrong JT (ed): Microbeam Analysis: 104-106. San Francisco Press. San Francisco
Putiš M, Hrdlička M, Uher P (2004) Lithology and granitoid magmatism of Lower Paleozoic in the Malé Karpaty Mts. crystalline complex. Miner Slov 36, 183-194 (in Slovak)
Sejkora J, Gabašová A (1995) Nesquehonite and widenmannite from Jáchymov, Krušné hory Mountains. Bull mineral-petrolog Odd Nár Muz (Praha) 3: 241-243 (in Czech)
Sejkora J, Ozdín D, Ďuďa R (2010) The supergene mineral association with brandholzite from Pernek, Malé Karpaty Mountains, Slovak Republic. J Geosci 55(2): 149-160
Stephan GW, MacGillavry CH (1972) The crystal structure of nesquehonite, MgCO3. 3H2O. Acta Cryst B28(4): 1031-1033
Števko M, Tuček P, Vitáloš J (2012) Occurrence of brandholzite at the Pezinok-Kolársky vrch antimony deposit. Minerál 20(2): 165-167 (in Slovak)
Uher P, Michal S, Vitáloš J (2000) The Pezinok antimony mine, Malé Karpaty Mountains, Slovakia. Mineral Rec 31(2): 153-162
Vennum WR (1986) Unusual magnesium and iron-bearing salts from West Antarctica. Antarct J US 21(5): 55-57
Yvon K, Jeitschko W, Parthé E (1977) Lazy Pulverix, a computer program for calculation X-ray and neutron diffraction powder patterns. J Appl Cryst 10: 73-74