Tolstykhite, Au₃S₄Te₆, a new mineral from Maletoyvayam deposit, Kamchatka peninsula, Russia

Abstract

Tolstykhite, ideally Au 3 S 4 Te 6 , is a new mineral from the Gaching ore occurrence of the Maletoyvayam deposit, Kamchatka peninsula, Russia. It occurs as individual anhedral grains up to 0.05 mm or as intergrowths with native Se, native Te and tripuhyite. Other associated minerals include calaverite, fischesserite, Cu-Te-rich fahlores [stibiogoldfieldite, its As-analogue, tennantite-(Cu), tetrahedrite-(Zn)], galena, gold, maletoyvayamite, minerals of famatiniteluzonite series, pyrite, baryte, ilmenite, magnetite, quartz and V-bearing rutile. Tolstykhite is bluish-gray, opaque with metallic lustre and gray streak. It is brittle and has an uneven fracture.

Auroselenide, AuSe, a new mineral from Maletoyvayam deposit, Kamchatka peninsula, Russia

“…The fact that observed bands in auroselenide are shifted to higher wavenumbers is probably due to the admixture of some S substituting Se in the composition of auroselenide (see below), as Hooke's Law predicts (Nakamoto, 1986). Analogous shifts have been reported as a consequence of S-Se substitution in permingeatite-famatinite-luzonite (Škácha et al, 2014), tetrahedrite-hakite (Škácha et al, 2017), chalcostibite-příbramite (Sejkora et al, 2018) and in tolstykhite-maletoyvayamite (Kasatkin et al, 2023;Tolstykh et al, 2020). The strong band at 171 cm -1 in auroselenide could be assigned to B 1g planar bending vibrations of the Au-Se bond.…”

“…This article continues a series of papers describing new mineral species of the Au–Te–Se–S system discovered at the Gaching ore occurrence of the Maletoyvayam deposit, Kamchatka peninsula, the Far East of the Russian Federation (60°19′51.87″N, 164°46′25.65″E). Three new minerals were reported previously: maletoyvayamite, Au 3 Se 4 Te 6 (Tolstykh et al , 2020), gachingite, Au(Te 1– x Se x ), 0.2 ≈ x ≤ 0.5 (Tolstykh et al , 2022a) and tolstykhite Au 3 S 4 Te 6 (Kasatkin et al , 2023). Auroselenide (pronounced a:-u-ro-se-le-naid; Cyrillic – ауроселенид) described below is, thus, the fourth mineral discovered at the deposit.…”

“…Gaching ore occurrence can be found elsewhere (Kalinin et al, 2012;Shapovalova et al, 2019;Sidorov et al, 2020;Tolstykh et al, 2018Tolstykh et al, , 2019Tolstykh et al, , 2020Tolstykh et al, , 2022aKasatkin et al, 2022).…”

“…Gaching, where all the new gold chalcogenides have been discovered, is one of the four ore occurrences comprising the Maletoyvayam deposit. A detailed geological description of the Maletoyvayam deposit and Gaching ore occurrence can be found elsewhere (Kalinin et al, 2012;Shapovalova et al, 2019;Sidorov et al, 2020;Tolstykh et al, 2018Tolstykh et al, , 2019Tolstykh et al, , 2020Tolstykh et al, , 2022aTolstykh et al, , 2022cKasatkin et al, 2023). The Maletoyvayam deposit is composed of andesites, tuffs and tuffaceous sandstones.…”

Kalithallite, K3Tl3+Cl6⋅2H2O, a new mineral with trivalent thallium from the Tolbachik volcano, Kamchatka, Russia

“…Kalithallite became the third mineral with species-defining trivalent thallium, after avicennite Tl 2 O 3 (Karpova et al, 1958) and chrysothallite K 6 Cu 6 Tl 3+ Cl 17 (OH) 4 ⋅H 2 O (Pekov et al, 2015c). Recently a fourth mineral with Tl 3+ was discovered, amgaite Tl 3+ 2 Te 6+ O 6 (Kasatkin et al, 2022). All these four minerals are extremely rare in Nature due to the particular and unusual formation conditions, under very high oxidising potential necessary for the appearance of Tl 3+ ; all other known minerals with species-defining Tl contain this element in univalent form.…”