| UDC 553.411(571.65) |
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Native Gold Typomorphism at the Front Au Lode, North-East of Russia |
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| © 2015 L. A. Solomentseva, I. S. Litvinenko |
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| North-East Interdisciplinary Scientific Research Institute n. a. N. A. Shilo, FEB RAS, Magadan |
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| E-mail: ;
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| This paper presents the results of studying typomorphic properties of native gold from the Front
gold-rare metal lode hosted in the Early Cretaceous leucocratic granites at the southeastern fl ank
of the Yana-Kolymian Gold Belt. The INCA energy dispersion spectrometer (X-Maw-50), EVO-50
scanning microscope and Camebax electron microprobe analyzer was used to examine ore minerals
in quartz veins. As a result, the mineralization type of the lode has been specifi ed, and the principal
typomorphic characters of native gold have been defi ned. These include crystallization of gold in
association with bismuth minerals (mainly maldonite), its occurrence in interstices and fractures of
earlier crystallized quartz and sulfi de-sulfoarsenide minerals, a very high fi neness, and quite a small
size. Native gold is mostly present in quartz (95,7 mass % of its total amount). Gold particles less
than 0,25 mm make up 95,2%. Finely dispersed gold smaller than 0,01 mm makes up 32,7% of the
native gold balance in the ore. Native gold is dominated by fi neness 890–950‰, and gold particles
of 910–920‰ are the most frequent within this interval. Tellurium is a typomorphic admixture in native
gold. Small quantities of very high-fi neness ramose-porous gold particles with bismuth oxides,
resulted from maldonite hypogenic decomposition, are noticed. Wide-spread maldonite permitted
researchers to classify the Front Au-rare metal lode as the maldonite-sulfotelluride mineralization
type. |
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| Keywords: gold-rare metal mineralization, gold, typomorphism. |
| Full text [In Russian] |
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