Summary
Granite-hosted tantalum mineralization was studied in the apical part of the Cínovec (Zinnwald) granite stock (eastern Krušné hory, Czech Republic). Samples of granite and greisen from drill hole CS-1 (1596m deep), situated in the centre of the granite body were analysed chemically and examined by electron microprobe. The apical, mainly lepidolite granite with 24 to 212 ppm Ta contains Ta-rich Mn columbite, uranmicrolite and strueverite (tantalian rutile). During greisenization the contents of Ta decreased or remained the same, but the newly formed cassiterite has elevated contents of Ta, probably due to remobilization from albitized granites. Niobium and tantalum mineralization can be linked with both magmatic and postmagmatic stages of granite evolution. Ta-rich columbite formed as a result of albitization dominant at the top of the granite cupola, whereas magmatic Nb-rich columbite is present throughout the entire profile of the granite stock.
The Cínovec granite stock is similar to some Palaeozoic Ta-bearing granite stocks in the Far East of Russia (Vosnesenka, Pogranichnyi) which are characterized by a vertical sequence of lepidolite, zinnwaldite and protolithionite granites. It shows minor similarities with Mesozoic amazonite-bearing granites in Transbaikalia (Etyka, Orlovka) and differs petrologically and mineralogically from the Palaeozoic lepidolite granite of Beauvoir (Échassieres) in France.
Zusammenfassung
Eine granitgebundene Tantalvererzung wurde im oberen Teil des Cínovec (Zinnwalder) Granitstocks (östliches Erzgebirge, Tschechische Republik) untersucht. Granit- und Greisenproben aus der Mitte des Granitkörpers wurden chemisch und mittels Elektronenstrahl-Mikrosonde analysiert. Der apikale Lepidolitgranit mit 24-212 ppm Ta führt Ta-reichen Mangancolumbit, Uranmikrolit und Strueverit (Tantalrutil). Im Verlauf der Vergreisung wurden die Tantalgehalte erniedrigt oder blieben gleich. Nur der neugebildete Kassiterit zeigt, wahrscheinlich als Folge der Remobilisierung aus den albitisierten Graniten, erhöhte Tantalgehalte. Die Niob- und Tantalmineralisation ist an das magmatische und postmagmatische Stadium der Granitentwicklung gebunden. Tantalreiche Columbite wurden durch die Albitisierung im Apikalteil des Granitstockes gebildet, während die niobreichen Columbite des magmatischen Stadiums über das ganze Bohrprofil hinweg vorkommen.
Der Zinnwalder Granitstock ist einigen paläozoischen Granitstöcken mit Tantalmineralisation im fernen Osten von Russland (Voznesenka, Pogranichnyi) ähnlich, welche durch eine vertikale Zonierung von Lepidolit-, Zinnwaldit- und Protolithionitgranit charakterisiert sind. Der Granitstock zeigt wenig ähnlichkeiten mit den mesozoischen Amazonitgraniten in Transbaikalien (Etyka, Orlovka) und unterscheidet sich petrologisch und mineralogisch vom paläozoischen Granit aus Beauvoir (Échassieres) in Frankreich.
Similar content being viewed by others
References
Beskin SM, Grebenikov AM, Matias VV (1994a) Khangilai pluton and associated Orlovka deposit of tantalum. Petrologiya 2: 68–87 (in Russian)
Beskin SN, Zagorskii VE, Kuznetsova LG (1994b) Etyka ore field of rare metals in Eastern Transbaikalia (Eastern Siberia). Geologiya rud mest 36: 310–325 (in Russian)
Breiter, K, Frýda J (1995) The Krupka tin deposit. In:Breiter, K, Seltmann R (eds) Excursion guide: mineralizationso f the Krušné hory Mts. (Erzgebirge). 3rd SGA Meeting. Czech Geol Survey Prague, pp 193–112
Černý P, Ercit TS (1985) Some recent advances in the mineralogy and geochemistry of Nb and Ta in rare-element granitic pegmatites. Bull Mineral 10: 499–532
Černý P, Ercit TS (1989) Mineralogy of niobium and tantalum. Crystal chemical relationships, paragenetic aspects and their economic implications. In:Möller P, Černý P, Saupé F (eds) Lanthanides, tantalum and niobium. Springer, Berlin Heidelberg New York Tokyo, pp 27–79
Cocherie A, Johan V, Rossi Ph, Štemprok M (1991) Trace element variations and lanthanide tetrad effect studied in a Variscan lithium albite granite: case of the Cínovec granite (Czechoslovakia). In:Pagel M, Leroy JL (eds) Source, transport and deposition of metals. Balkema, Rotterdam, pp 745–749
Ginsburg AI, Fel'dman LG (1974) Deposits of tantalum and niobium. In:Smirnov VI (ed) Ore deposits of the USSR, vol 3. Nedra, Moskva, pp 353-402 (in Russian)
Johan V, Johan Z (1993) Accessory minerals of the Cínovec (Zinnwald) granite cupola, Czech Republic, part 1. Nb-, Ta-, and Ti-bearing oxides. Mineral Petrol 49: 1–21
Johan Z, Johan V (1994) Oxylluorures de terres rares de la coupole granitique de Cínovec (Zinnwald), République tcheque. CR Acad Sci Paris 318: 1333–1340
Pollard P (1989) Geochemistry of granites associated with tantalum and niobium mineralization. In:Möller P, Černý P, Saupé F (eds) Lanthanides, tantalum and niobium. Springer, Berlin Heidelberg New York Tokyo, pp 145–168
Povarennykh MYu (1994) On polygenic nature of tantalum minerals in amazonite-albite rare-metal granites. Zapiski Vseros mineral obschestva 73: 33–46 (in Russian)
Raimbault L, Azencott C (1987) Géochimie des éléments majeurs et traces du granite a métaux rares de Beauvoir (Sondage GPF, échassieres). Géologie de la France 2–3: 189–198
Raimbault L, Autran A, Cuney M, Fonteilles M, Rossi Ph (1991) Mineralogical and geochemical profile through the (Échassieres) Ta-Li-Sn mineralized granite (French Massif Central). Bull Soc géol France 162: 913–915
Rossi Ph, Autran A, Azencott C, Burnol L, Cuney M, Johan V, Kosakevitch A, Ohnenstetter D, Monier G, Piantone P, Raimbault L, Viallefond L (1987) Logs pétrographique et géochimique du granite de Beauvoir dans le sondage "échassieres I" Minéralogie et géochimie comparées. Géologie de la France 2–3: 113–122
Rub AK (1980) Typomorphic peculiarities of the minerals associated with tantalum and tin mineralization. Nedra, Moskva, 150pp (in Russian)
Rub AK, Chistyakova NI, Rub MG (1994) Composition of tantalum mineralization of the Voznesenka ore knot (Maritime reigion). Dokl Akad Nauk 334: 763–767 (in Russian)
Rub AK, Štemprok M, Rub MG (1997) Ta mineralization in rare-metal granites of the Cfnovec granite massif (Czechia). Dokl Akad Nauk 352: 795–798 (in Russian)
Rub MG, Rub AK (1994) Petrology of the rare metal granites of the Voznesenka ore district. Petrologiya 2: 43–67
Rub MG, Pavlov VA, Rub AK, Stemprok M, Drábková E, Drábek M (1983) Vertical zoning of the Cínovec granite massif of lithium-fluorine granites (CSSR). In:Bogatikov OA, Borsuk AM (eds) Correlation of magmatic rocks of Czechoslovakia and some districts of the USSR. Izd. Nauka, Moskva, pp 10–137 (in Russian)
Štemprok M (1961) Genetische Untersuchung der flachfallenden Gänge ouf der Erzlagerstätte Cfnovec (Zinnwald) im Erzgebirge. Sborník ÚÚG 26: 455–528
Štemprok M (1965) Petrography and the vertical extent of mineralization in the Cfnovec Granite cupola. Sborník geol věd, Rada LG 5: 7–106 (in Czech)
Štemprok M (1989) Rare-earth elements in the rocks of the Cfnovec granite cupola (Czechoslovakia). Bull Geol Surv Prague 64: 1–15
Štemprok M, Šulcek Z (1969) Geochemical profile through an ore-bearing lithium granite. Econ Geol 64: 392–404
Štemprok M, Novák JK, David J (1994) The association between granites and tin-tungsten mineralization in the eastern Krušné hory (Erzgebirge), Czech Republic. In:Gehlen von K et al. (eds) Monograph series on mineral deposits. Gebrueder Borntraeger, Berlin Stuttgart, pp 97–129
Štemprok M Seltmann R, Breiter K (1995) The Cfnovec/Zinnwald Sn-W-Li deposit. In:Breiter K, Seltmann R (eds) Excursion guide: ore mineralizations of the Krušné hory Mts. (Erzgebirge), 3 SGA Meeting, Czech Geol Survey, pp 77-83
Tischendorf G, Just G, Gottesmann G (1988) Distribution of elements at a contact of albite granite/rhyolite, Zinnwald, Erzgebirge, GDR. Chem Erde 48: 155–162
Wang Ru Chen, Fontan F, Monchoux P (1987) Interrélations et évolution comparée de la cassitérite et des niobotantalates dans les différents facies du granite de Beauvoir (Massif de Échassieres). Géologie de la France 2–3: 237–245
Author information
Authors and Affiliations
Additional information
With 11 Figures
Rights and permissions
About this article
Cite this article
Rub, A.K., Štemprok, M. & Rub, M.G. Tantalum mineralization in the apical part of the Cínovec (Zinnwald) granite stock. Mineralogy and Petrology 63, 199–222 (1998). https://doi.org/10.1007/BF01164151
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF01164151