Mineralogical and Geochemical Features of Native Gold in Combustion Products of Coal from the Erkovetsky Deposit (Upper Amur Region)

Abstract

A bulk coal sample from the Erkovetsky deposit is studied at Amur experimental and engineering facility. Separate fractions of coal combustion products (slag, fly ash, and sludge) are obtained for the first time, in which the morphology, fineness of gold and composition of inclusions have been studied. A consistent decrease in gold size and content is determined after coal combustion, transportation in a gas-smoke stream, and subsequent condensation. A comparative analysis of gold in the combustion products of coal and in ore bodies of the mountain-folded framing of the Zeya-Bureya basin is carried out, the ways of gold migration to peat bogs are considered.

Gold-Bearing Brown Coal Deposits of the Zeya–Bureya Sedimentary Basin (East Russia): Fundamental Model of Formation

“…Spongy gold (Figure 7c) with voids and caverns could be seen filled with organic substances. We propose that [25] they reflected the results of dissolved gold compounds penetrating into coals, infilling the cracks and pores at the initial stage of catagenesis. Gold remains in a dendritic form when the organics are burned.…”

“…Samples weighing 5-6 kg were collected using point sampling. Channel sampling of coal weighing 6 and 12 kg was conducted in a 0.5-0.7 m section [22][23][24][25]. In 2018, studies on coal and ash deposits were conducted at the Federal Research Center for Coal and Coal Chemistry, Siberian Branch of the Russian Academy of Sciences (FITSUiU SB RAS), Kemerovo.…”