Structure and composition of kenyaite after thermal annealing
M.V. Shtenberg, I.A. Blinov, V.A. Popov, R.T. Zaunillina, M.A. Rassomakhin
UDК 549.62 (470.56)
Kenyaite Na2Si22O41(OH)8 ·6H2O previously found at the cacholong occurrence in the Orenburg region (South Urals) was studied using physicochemical methods. Its transformation to quartz after thermal annealing at 750 °C for several hours was of particular interest. The results of chemical analysis, electron microscopy, and infrared spectroscopy allowed us to broaden understanding of this efect. It is found that Na is removed by water vapors via fractures and pores and is deposited in them.
Figure 4. Table 2. References 9.
Key words: kenyaite, South Urals, annealing, quartz.
M.V. Shtenberg, Institute of Mineralogy UB RAS, Miass, Chelyabink district, 456317 Russia; shtenberg@mineralogy.ru
I.A. Blinov, Institute of Mineralogy UB RAS, Miass, Chelyabink district, 456317 Russia;
V.A. Popov, Institute of Mineralogy UB RAS, Miass, Chelyabink district, 456317 Russia;
R.T. Zaunillina, Institute of Mineralogy UB RAS, Miass, Chelyabink district, 456317 Russia;
M.A. Rassomakhin, Ilmeny State Reserve, Miass, Chelyabink district, 456317 Russia
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МINERALIGY № 4 2018