First Evidence of the Archean Age of Orogenic Gold of the Russian Part of the Karelian Craton (Fennoscandian Shield): Sm–Nd Mineral Isochron for Gold-Bearing Metasomatites of the Novye Peski Deposit

Forms of Gold and Arsenic in Surface Sediments at the Novye Peski Gold Deposit and Their Sorption by Humic Acid

“…The sample in the sequential extraction experiment was 1 g and for HA and FA extraction −5 g. In the experiment of gold and arsenic sorption by solid humic acid, standard solutions of gold (GSO 8429-2003) and arsenic (III) (GSO 7976-2001) with a background of 2.0 M and 0.1 M HCl, respectively were used. HA was extracted from an air-dry soil sample by double extraction with a 0.1 mol/dm 3 NaOH solution (soil solution ratio 1:10). Then, a saturated Na2SO4 solution (20% of the extract volume) was added to the alkaline extract to coagulate colloidal particles and centrifuged for 1 h at 12,000 rpm.…”

“…To study the sorption of ions on HA, solutions containing gold and arsenic ions with concentrations of 5, 10, 25, 35, 50, 75, and 100 µg/cm 3 were prepared separately by diluting the standards solutions with 1 mmol/dm 3 HCl. The pH of the prepared solutions was in the range 3.0-3.1.…”

“…Gold and arsenic forms were studied in loose sediments in the Novye Peski gold deposit area (Karelia Republic, Russia). The gold-sulfo-arsenide deposit Novye Peski is located within the Segozero-Vedlozero Archean greenstone belt and is attributed to the category of a small deposit with indicated reserves of 0.97 t (2.7 g/t Au), inferred reserves of 4.18 t (2.9 g/t Au), and approved speculative resources of 10.8 t [3]. The main types of host rocks within the deposit are metamorphosed basalts, basaltic andesites and their tuffs, amphibolites over gabbro or gabbro-amphibolites, including garnet and epidote with magnetite and ilmenite.…”

First data on the chemical composition of natural waters at the gold deposit “Novye Peski” (South Karelia, Russia)

“…The gold-bearing sulfide-arsenide mineralization was identified in 1988 [3]. As a result of the work of "Onego-Zoloto" in 2007-2013, "Novye peski" was transferred to the rank of a deposit with Au in proved reserves 0.97 t, Au 2.7 g/t, probable reserves 4.18 t, Au 2.9 g/t and inferred exploration potential 10.8 t Au [4]. Mineralization is limited to metasomatized rocks that have undergone cataclasis and foliation.…”

“…Ore metasomatites are represented by ilmenite-quartz-garnet-amphibole, ilmenite-quartz-garnet-feldspar-amphibole, and titanite-carbonate-biotite-chlorite-epidote (clinozoisite) metasomatites [5]. The mineral composition of ore zones according to our data, as well as according to a literature review [2,4] is presented:  Silicates: quartz, feldspar (albite), amphibole (ferrochermakite, ferroactinolite, grunerite, Fe-hornblende), pyroxene (ferropijonite, ferroaugite), chlorite (brunswigitechamosite), garnet (pyralspite-ugrandite series with a high content of grossular minal (20-50 %)), epidote (clinozoisite), biotite, titanite.  Oxides: magnetite, ilmentite, scheelite, wolframite.…”