Pseudomorphous Rhythmic-Banded and Oscillatory Aggregates of Tetrahedrite-Tennantite at the Gold Deposit Darasun (Eastern Transbaikalia, Russia): a Result of the Coupled Dissolution-Reprecipitation Replacement Reactions

2018 ◽  
Vol 483 (1) ◽  
pp. 89-93
Author(s):  
N. Lyubimtseva ◽  
◽  
N. Bortnikov ◽  
S. Borisovskiy ◽  
S. Vikent’eva ◽  
...  
Keyword(s):  
Gold Deposit ◽  
Eastern Transbaikalia

Fülöppite Pb3Sb8S15 from the Darasun Volcanogenic–Plutonogenic Gold Deposit (Eastern Transbaikalia)

2020 ◽  
Vol 75 (6) ◽  
pp. 616-620
Author(s):  
E. M. Spiridonov ◽  
N. N. Krivitskaya ◽  
I. A. Bryzgalov ◽  
N. N. Korotaeva ◽  
K. N. Kochetova
Keyword(s):  
Gold Deposit ◽  
Eastern Transbaikalia

Disseminated ores of the Darasun gold deposit (Eastern Transbaikalia) and their genesis

2008 ◽  
Vol 422 (1) ◽  
pp. 1025-1027 ◽  
Author(s):  
V. Yu. Prokof’ev ◽  
N. S. Bortnikov ◽  
A. V. Volkov ◽  
I. A. Baksheev ◽  
L. D. Zorina
Keyword(s):  
Gold Deposit ◽  
Eastern Transbaikalia

Metasomatites of the Kara gold deposit (Eastern Transbaikalia)

2007 ◽  
Vol 48 (11) ◽  
pp. 901-912 ◽  
Author(s):  
Z.I. Kulikova ◽  
A.M. Spiridonov ◽  
L.D. Zorina
Keyword(s):  
Gold Deposit ◽  
Eastern Transbaikalia

scholarly journals Coupled dissolution–precipitation reactions of tennantite-tetrahedrite minerals in the Darasun gold deposit (Eastern Transbaikalia, Russia)

2019 ◽  
Vol 61 (6) ◽  
pp. 38-57
Author(s):  
N. G. Lyubimtseva ◽  
N. S. Bortnikov ◽  
S. E. Borisovsky ◽  
O. V. Vikent’eva ◽  
V. Yu. Prokofiev
Keyword(s):  
Gold Deposit ◽  
Negative Correlation ◽  
Crystallization Temperature ◽  
Miscibility Gap ◽  
Sharp Drop ◽  
Initial Stage ◽  
Eastern Transbaikalia ◽  
Fluid Cooling ◽  
Precipitation Reactions ◽  
Complete Transformation

Heterogeneous rhythmic-zonal aggregates of tennantite-IV replaced partly or completely early homogeneous Zn-tetrahedrite-I and euhedral (Fe-Zn)-tennantite-I crystal were found in ores of the Darasun gold deposit. Different replacement stages of fahlore were observed. It initiates at grain boundaries and is terminated by a complete transformation into pseudomorphic newly formed (Zn-Fe)-tennantite-IV aggregates rimed with Zn-tetrahedrite-IV. These aggregates associated intimately with bournonite and galena and their deposition initiated the pseudomorph formation. EMPA revealed that (Fe-Zn)-tetrahedrite richer in As relative to Zn-tetrahedrite-I was deposited at initial stage. Tennantite with wide variation in Sb/(Sb + As) and Fe/(Fe + Zn) ratios predominantes in heterogenous zonal aggregates of (Fe-Zn)-tetrahedrite-tennantite-IV. A negative correlation between the Sb/(Sb + As) and Fe/(Fe + Zn) was found in these minerals. In each site at the contact between Zn-tetrahedrite-I and newly formed (Fe-Zn)-tetrahedrite-tennantite-IV a miscibility gap between As and Sb a sharp drop in the Sb/(Sb + As) ratio and an increase in Fe/(Fe + Zn) ratio occur. Sharp saw-shape boundaries between Zn-tetrahedrite-I and tennantite-IV and voids in newly formed aggregates are considered to be evidence for couple dissolution-precipitation reactions. The dissolution was initiated due disequilibrium between Zn-tetrahedrite-I and an undersaturated fluid resulted from deposition of galena and bournonite. Precipitation of tetrahedrite-tennantite-IV occurred under oscillation in Sb/(Sb + As) and Fe/(Fe + Zn) ratios due to the metal and semimetal contents in the fluid. Crystallization temperature of zonal-heterogenous tennantite-IV aggregates was calculated by sphalerite-fahlore geothermometer which shows (134161) 20 С. Instability of early Zn-tetrahedrite-I resulted from fluid cooling, decreasing in fluid salinity, changing in tetrahedrite and tennantite solubility due to an evolution of migration conditions of semimetals.

Coupled Dissolution–Precipitation Reactions of Tennantite–Tetrahedrite Minerals in the Darasun Gold Deposit (Eastern Transbaikalia, Russia)

2019 ◽  
Vol 61 (6) ◽  
pp. 530-548
Author(s):  
N. G. Lyubimtseva ◽  
N. S. Bortnikov ◽  
S. E. Borisovsky ◽  
O. V. Vikent’eva ◽  
V. Yu. Prokofiev
Keyword(s):  
Gold Deposit ◽  
Eastern Transbaikalia ◽  
Precipitation Reactions

scholarly journals Coexisting bournonite-seligmanite and tennantite-tetrahedrite solid solutions in Darasun gold deposit (Eastern Transbaikalia, Russia): Estimation of the mineral formation temperature

2019 ◽  
Vol 61 (3) ◽  
pp. 85-104
Author(s):  
N. G. Lyubimtseva ◽  
N. S. Bortnikov ◽  
S. E. Borisovsky
Keyword(s):  
Gold Deposit ◽  
Solid Solutions ◽  
Native Gold ◽  
Formation Temperature ◽  
Mineral Formation ◽  
Compositional Evolution ◽  
Complete Solid Solution ◽  
Mineral Associations ◽  
Eastern Transbaikalia ◽  
First Time

Mineral associations, intergrowth features, chemical composition and Sb and As distribution in coexisting fahlore and bournonite-seligmanite solid solutions in the Darasun gold deposit were studied. For the first time the almost complete solid solution was found between bournonite and seligmanite with a continuous isomorphism between Sb and As in the range of Sb/(Sb + As) ratios from 0.21 to 1.00 in the Darasun deposit by EMPA. The composition of the fahlore coexisting with bournonite varies widely: Sb/(Sb + As) ratios 0.03-0.96 and Fe/(Fe + Zn) ratios 0.36-0.87. The coupled compositional evolution from early antimony to late arsenic in coexisting solid solutions has been established. Based on the investigation of the Sb and As distribution between coexisting fahlore and bournonite-seligmanite, the temperatures of their joint deposition and, as a result, of the productive stage, in which they are closely associated with native gold and tellurides (90–335 °С), are estimated.

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