Ag-Bearing Tetrahedrite-(Cd), (Cu,Ag)6(Cu4Cd2)Sb4S13, from Galenite-Fluorite Deposit Kon-Dara (South-Western Pamir) – First Discovery in Tajikistan

Мұқаба

Дәйексөз келтіру

Толық мәтін

Ашық рұқсат Ашық рұқсат
Рұқсат жабық Рұқсат берілді
Рұқсат жабық Тек жазылушылар үшін

Аннотация

Tetrahedrite-(Cd), with the ideal formula Cu10Cd2Sb4S13, is a member of the tetrahedrite series of the tetrahedrite group with a predominance of Cd at the C position typically occupied by divalent metals. Cadmium end-members from the tetrahedrite group are rare: they were found in 15 deposits and ore occurrences. The article reports on a new discovery site of Ag-bearing tetrahedrite-(Cd) at the Kon-Dara mineral deposit (Southwestern Pamirs, Tajikistan) and summarizes the known data on rare Cd-bearing fahlores with Cd content from 1 to 12.31 wt. %. Ag-bearing tetrahedrite-(Cd) at the Kon-Dara deposit occurs as xenomorphic segregations 10–35 µm in size in association with tetrahedrite-(Fe), tetrahedrite(Zn), galena, polybasite, and chalcopyrite, which replace bournonite. According to the EPMA data, its composition averaged over seven analyzes (in wt. %) is as follow: Ag 16.17, Cu 25.19, Cd 10.09, Fe 0.38, Zn 0.09, Pb 0.13, Sb 25.55, As 0.18, S 22.34. The empirical formula calculated based on 29 atoms per the unit is (Cu7.40Ag2.80)Σ10.20(Cd1.68Fe0.13Zn0.03Pb0.01)Σ1.84(Sb3.92As0.04)Σ3.96S13.00. The composition of the tetrahedrite-(Cd) from Kon-Dara is similar to those from the Tyndrum Pb-Zn mineralization in Scotland, the Clara baryte-fluorite-(Ag,Cu) mine in Germany, and the Xaitishan Pb-Zn deposit in China. The formation temperature of Ag-bearing tetrahedrite-(Cd) at the Kon-Dara deposit is estimated to has been at about (170-140) ± 20°C.

Толық мәтін

Рұқсат жабық

Авторлар туралы

N. Lyubimtseva

Institute of Geology of Ore Deposits, Petrography, Mineralogy, and Geochemistry of the Russian Academy of Sciences

Хат алмасуға жауапты Автор.
Email: luy-natalia@yandex.ru
Ресей, Moscow

N. Bortnikov

Institute of Geology of Ore Deposits, Petrography, Mineralogy, and Geochemistry of the Russian Academy of Sciences

Email: luy-natalia@yandex.ru

Academician of the RAS

Ресей, Moscow

V. Gekimyants

Fersman Mineralogical Museum of the Russian Academy of Sciences

Email: luy-natalia@yandex.ru
Ресей, Moscow

S. Borisovsky

Institute of Geology of Ore Deposits, Petrography, Mineralogy, and Geochemistry of the Russian Academy of Sciences

Email: luy-natalia@yandex.ru
Ресей, Moscow

P. Plechov

Fersman Mineralogical Museum of the Russian Academy of Sciences

Email: luy-natalia@yandex.ru
Ресей, Moscow

Әдебиет тізімі

  1. Biagioni C., George L. G., Cook N. J., Makovicky E., Moëlo Y., Pasero M., Sejkora J., Stanley C. J., Welch M. D., Bosi F. The tetrahedrite group: Nomenclature and classification. Am. Miner. 2020. V. 105. P. 109–122.
  2. Warr L. N. IMA–CNMNC approved mineral symbols // Mineralogical Magazine. 2021. V. 85. № 3. P. 291–320.
  3. Pattrick R. A. D. Microprobe analyses of cadmiumrich tetrahedrites from Tyndrum, Perthshire, Scotland // Mineralogical Magazine. 1978. V. 42. № 322. P. 286–288.
  4. Pattrick R. A. D. Pb-Zn and minor U mineralization at Tyndrum, Scotland // Mineralogical Magazine. 1985. V. 49. № 354. P. 671–681.
  5. Jia D., Fu Z., Zhang H., Zhao C. The first discovery of Cd-freibergite in China // Acta Miner. Sinica. 1988. V. 8. P. 136–137 (in Chinese with English abstract).
  6. Pascua M. I., Muriego A., Pellitero E., Babkine J., Dusausoy Y. Sn-Ge-Cd-Cu-Fe-bearing sulfides and sulfosalts from the Barquilla deposit, Salamanca, Spain // Canadian Mineralogist. 1997. V. 35. P. 39–52.
  7. Паленова Е. Е., Блинов И. А., Заботина М. В. Минералы серебра в кварцевых жилах рудопроявления золота Красное (Бодайбинский район) // Минералогия. 2015. № 2. С. 9–17.
  8. Bayerl R., Desor J., Möhn G. New Minerals for the Clara mine, Oberwolfach, Germany. 2022. https://www.mindat.org/reference.php?id=16098796
  9. Sejkora J., Biagioni C., Škácha P., Musetti S., Kasatkin A. V., Nestola F. Tetrahedrite-(Cd), Cu6(Cu4Cd2) Sb4S13, from Radětice near Příbram, Czech Republic: the new Cd member of the tetrahedrite group // European Journal of Mineralogy. 2023. V. 35. № 6. P. 897–907.
  10. Тихомирова В. Д. Особенности состава блеклых руд месторождений формации медистых песчаников на Севере Урала / Теория, история, философия и практика минералогии: Материалы IV Междунар. минерал. семинара. 2006. С. 193–195.
  11. Плотинская О. Ю., Ковальчук Е. В. Блеклые руды Cu-(Mo)-порфировых месторождений Урала // Минералогия. 2022. Т. 8. № 3. С. 5–22.
  12. Biagioni C., Kasatkin A., Sejkora J., Nestola F., Škoda R. Tennantite-(Cd), Cu6(Cu4Cd2)As4S13, from the Berenguela mining district, Bolivia: the first Cd-member of the tetrahedrite group // Mineral. Mag. 2022. V. 86. P. 834–840.
  13. Воропаев А. В., Спиридонов Э. М., Щибрик В. И. Тетраэдрит-Cd – первая находка в СССР // Доклады АН СССР. 1988. Т. 300. № 6. С. 1446–1448.
  14. Dobbe R. T. M. Manganoan-cadmian tetrahedrite from the Tunaberg Cu-Co deposit, Bergslagen, central Sweden // Mineral. Mag. 1992. V. 56. P. 113–115.
  15. Voudouris P. C. Conditions of formation of the mavrokoryfi high-sulfidation epithermal Cu–Ag–Au–Te mineralization (Petrota Graben, NE Greece) // Mineralogy and Petrology. 2011. V. 101. P. 97–113.
  16. Mikuš T., Vlasáč J., Majzlan J., Sejkora J., Steciuk G., Plášil J., Rößler C., Matthes C. Argentotetrahedrite(Cd), Ag6(Cu4Cd2)Sb4S13, a new member of the tetrahedrite group from Rudno nad Hronom, Slovakia // Mineralogical Magazine. 2023. V. 87. № 2. P. 262–270.
  17. Škácha P., Sejkora J., Palatinus L., Makovicky E., Plášil J., Macek I., Goliáš V. Hakite from Příbram, Czech Republic: compositional variability, crystal structure and the role in Se mineralization // Mineralogical Magazine. 2016. V. 80. № 6. P. 1115–1128. https://doi.org/10.1180/minmag.2016.080.038
  18. Pattrick R. A. D., Hall A. J. Silver substitution into synthetic zinc, cadmium, and iron tetrahedrites // Mineralogical Magazine. 1983. V. 47. № 345. P. 441–451.
  19. Юшкин Н. П. Новая кадмиевая разновидность тетраэдрита // Доклады АН СССР. 1978. Т. 242. № 2. С. 246–249.
  20. Бортников Н. С., Коваленкер В. А., Гейнке В. Р., Тронева Н. В., Раздолина Н. В. Химический состав и парагенетические ассоциации сульфосолей в серебро-полиметаллических месторождениях Средней Азии / В кн.: Метасоматоз, минералогия и вопросы генезиса золотых и серебряных месторождений. М.: Наука, 1986. С. 146–167.

Қосымша файлдар

Қосымша файлдар
Әрекет
1. JATS XML
2. Fig. 1. Sample FMM_1_74896 from the Kon-Dara deposit (South-West Pamir, Tajikistan) with Ag-bearing tetrahedrite-(Cd). Collection of the Fersman Mineralogical Museum. A.E. Fersman RAS (Moscow, Russia). Mineral designations in accordance with [2]: Bnn - bournonite, Sp - sphalerite, Qz - quartz, Sid - siderite

Жүктеу (28KB)
3. Fig. 2. Mineral assemblages in the anschliff from sample FMM_1_74896 (Kon-Dara, Tajikistan). (a, b) Accretion of bournonite-I (Bnn), galena-I (Gn), sphalerite (Sp) and pyrite (Py). (c) Sphalerite contains a network of veins (fracture system) filled with pyrite, galena-II and chalcopyrite. Pyrite composes the veins with a thickness of 20-60 µm. Galenite-II develops along veins 10-50 microns thick in sphalerite and inside pyrite veins, partially replacing it. (d) Burnonite-I contains galena-chalcopyrite (10-20 µm) and monomineral tetrahedrite (5-10 µm) veins with close xenomorphic intergrowths of galena-II, chalcopyrite and tetrahedrite (Ttr) in their swells; (e, f) A section of a polymineral vein with a 300 µm blow in bournonite-I and its enlarged fragment. Close junctions of galena-II, chalcopyrite, tetrahedrite and bournonite-II. Photographs in reflected light

Жүктеу (187KB)
4. Fig. 3. Grain from monofraction FMM_FN1086 (sample FMM_1_74896, Kon-Dara, Tajikistan) in which Ag-bearing tetrahedrite-(Cd) was detected. (a) Burnonite-I (Bnn) is replaced by an aggregate composed of galena-II (Gn), chalcopyrite (Ccp), tetrahedrite (Ttr), polybasite (Plb) and bournonite-II. Fragment of a vein like those shown in Fig. 2. Image in reflected light; (b) The same in crossed nicols. Bournonite-I shows polysynthetic twinning; (c) The same in back-scattered electrons (BSE). The central part of the vein is composed of galena and confined chalcopyrite. Tetrahedrite interstices between galena and chalcopyrite grains, gravitating towards the peripheral part of the vein. Polybasite is developed along the contact between tetrahedrite (and/or galena-II) and bournonite-I

Жүктеу (55KB)
5. Fig. 4. Magnified fragments of the grain shown in Fig. 3, with Ag-containing tetrahedrite-(Cd). (a) Magnified fragment of the grain from Fig. 3а. Tight intergrowths of tetrahedrite, galena-II, chalcopyrite and polybasite within a bournonite-I aggregate. Chalcopyrite has dendrite-like outcrops that intrude and secrete galena-II and also intrude into tetrahedrite. (b-d) Enlarged fragments of Figs. 3c and 4a: (b) Polybasite forms close accretions with tetrahedrite and galena-I at the contact with bournonite-II. (c-d) Close intergrowths of tetrahedrite composed of the three outermost Fe-, Zn- and Cd-members of the tetrahedrite solid solution, galena-II, polybasite, bournonite-II and chalcopyrite within the bournonite-I aggregate. Tetrahedrite-(Cd) forms close assemblages with polybasite and is located closest of the three tetrahedrites to the bournonite-I contact. Along the border of tetrahedrite-(Cd) and bournonite-I it is characterised by the presence of pores and absence of direct contact of these two minerals. Tetrahedrite-(Fe) gravitates to the contact with chalcopyrite. Tetrahedrite-(Zn) occupies an intermediate position between tetrahedrite-(Cd) and tetrahedrite-(Fe). Burnonite-II is present in galena, tetrahedrite and polybasite in the form of elongated inclusions

Жүктеу (101KB)
6. Fig. 5. Compositions of tetrahedrite-(Fe) and tetrahedrite-(Zn) (marked with orange circles) coexisting with tetrahedrite-(Cd) plotted on a graph borrowed from [25]. Isotherms and regions of immiscibility of paleo ore (Cu,Ag)10(Fe,Zn)2As4S13 at 100, 140, 170, 180 and 185°C calculated for ΔḠ*3s = 10 kJ/mol (left) and ΔḠ*3s = -10 kJ/mol (right) are drawn

Жүктеу (27KB)
7. Fig. 6. Contents of divalent metals Cd, Zn and Fe in minerals of the faint ore group from the Kon-Dara deposit (Tajikistan) (this work) (a) in comparison with those from the deposits Tindrum (Scotland) (the graph is constructed by the authors on the basis of analyses given in [3, 4]) (b) and Barquilla (Spain) (Fig. 7 from [6] with additions) (c)

Жүктеу (32KB)
8. Fig. 7. Cd contents vs. Ag (a), Sb (b), Fe (c) and Zn (d) contents (in f.c.) in cadmium blister ores. The graphs are based on a generalised table of analyses (Appendices 3 and 4) obtained from various sources. Formula coefficients in minerals are calculated on the basis of 29 atoms in the formula

Жүктеу (52KB)
9. Fig. 8. Distribution of divalent metals Cd, Zn and Fe in Cd-bearing faint ores known in the world. All analyses from Appendices 3 and 4 are plotted except for Cd-bearing argentotetrahedrite-(Mn) and hakite-(Hg)

Жүктеу (16KB)
10. Supplementary 1

Жүктеу (23MB)
11. Supplementary 2

Жүктеу (24MB)
12. Supplementary 3
Жүктеу (318KB)
13. Supplementary 4
Жүктеу (283KB)
14. Supplementary 5
Жүктеу (30KB)

© Russian Academy of Sciences, 2024