O.V. Tsilmak, NEW DATA OF THE CARBONATE ONYX'S MINERAL COMPOSITION FROM THE YEVHEN LAZARENKO MINERALOGICAL MUSEUM'S COLLECTION (GAURDATSKA CAVE, TURKMENISTAN)
https://doi.org/10.15407/mineraljournal.47.01.055
UDC [549.74(575.4)]+[069:5(477)]
NEW DATA OF THE CARBONATE ONYX'S MINERAL COMPOSITION FROM THE YEVHEN LAZARENKO MINERALOGICAL MUSEUM'S COLLECTION (GAURDATSKA CAVE, TURKMENISTAN)
O.V. Tsilmak, PhD (Geology), Chief Custodian of the Museum's Funds
E-mail: oksana.tsilmak@lnu.edu.ua; orcid: 0009-0009-5701-2866
K.A. Burban, Head of the Laboratory
E-mail: kateryna.burban@lnu.edu.ua; orcid: 0009-0002-9961-5680
U.I. Bornyak, PhD (Geology), Associate Professor
E-mail: ulyana.bornyak@lnu.edu.ua; orcid: 0000-0003-1214-4821
Ivan Franko Lviv National University
4, Hrushevsky Str., Lviv, Ukraine, 79005
Language: Ukrainian
Mineralogical journal 2025, 47 (1): 55-63
Abstract: The results of complex mineralogical studies of carbonate onyx from the Yevhen Lazarenko Mineralogical Museum's collection are given. The structural and textural features of the dripstone type carbonate aggregate were established by the methods of optical and electron microscopy. Polarized light microscopy, chemical and X-ray structural methods revealed that the brown color of carbonate onyx probably is coursed by inclusions of organic material in calcite. Microprobe analysis determined the mineral composition and chemical composition of carbonate onyx minerals. The main mineral of carbonate onyx is calcite, which contains 1.0—7.8 wt.% ZnO. In the carbonate onyx, irregularly shaped Mg-Ca-Zn carbonate up to 50 μm in size were also found, the chemical composition of which does not correspond to calcite, dolomite, smithsonite, or minrecordite. It is assumed that based on the stoichiometric ratios of the main components, the unknown Mg-Ca-Zn carbonate may belong to the structural type AB3(CO3)4 and may be isostructural with hanthite CaMg3(CO3)4, and its probable formula is CaZn3(CO3)4.
Keywords: calcite, carbonate onyx, chemical composition, Gaurdatska Cave.
References / Література
Faust, G.T. (1953), Amer. Mineral., Vol. 38, No. 1-2, pp. 4-24.
Garavelli, C.G., Vurro, F. and Fioravanti, G.C. (1982), Mineral. Rec., Vol. 13, No. 3, pp. 131-136.
Ghassemi, M.R. and Garzanti, E. (2019), Geopersia, Vol. 9, No. 1, pp. 125-140. https://doi.org/10.22059/geope.2018.265613.648416
Lazarev, I.S. and Filenko, G.D. (1976), Peshchery, Iss. 16, Perm State Univ., Perm, pp. 45-63 [in Russian].
[Лазарев, И.С., Филенко, Г.Д. (1976), Пещеры. Вып. 16. Пермь. С. 45—63.]
Liu, Xin; Lu, Xiancai; Liu, Xiandong and Zhou, Huiqun (2015), Amer. Mineral., Vol. 100, No. 1, pp. 172-180. https://doi.org/10.2138/am-2015-4815
Makhrovsky, V.M., Dinzhos, R.V. and Lysenkov, E.A. (2019), X-ray structural analysis, Publ. house Ilion, Mykolaiv, 150 p. [in Ukrainian].
[Махровський, В.М., Дінжос, Р.В., Лисенков, Е.А. (2019), Рентгеноструктурний аналіз. Миколаїв: Іліон. 150 с.]
Maltsev, V.A. and Self, C.A. (1992), Proc. Univ. Bristol Spelaeol. Soc., Vol. 19, No. 2, pp. 117-149.
Nassau, K. (1978), Amer. Mineral., Vol. 63, pp. 219-229.
Yablokova, N. (2013), Fata Morgana Cave (Gaurdakskaya). History of discovery, Int. Spelaeol. Journ. "Svet", No. 39, pp. 68-78 [in Russian].
[Яблокова, Н. (2013), Пещера Фата Моргана (Гаурдакская). История открытия. Журнал "Свет". № 39. С. 68—78.]