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IN THIS ISSUE This New Mineral Names has entries for 6 new minerals, including, beusite-(Ca), graftonite-(Ca), graftonite-(Mn),hyrslite, magnesiobeltrandoite-2N3S, and zincovelesite-6N6S. Chemistry and crystal-structure refinement indicate that the M(1) siteis occupied dominantly by Mn in graftonite-(Mn) and by Ca in graftonite-(Ca)and beusite-(Ca). In graftonite-(Mn) and -(Ca) the M(2) andM(3) sites are occupied by Fe[sup 2+] and Mn[sup 2+], with Fe[sup 2+] dominant over Mn[sup 2+]at the aggregate M(2)+M(3) sites. [Extracted from the article]

This paper describes specific features of isomorphism of unusual amphiboles containing up to 23 wt% ZnO and up to 1.3 wt% CuO from sulfide-free metasomatic rocks of the "Mixed Series" metamorphic complex, Pelagonian Massif, Republic of North Macedonia, in which chalcophile elements (Pb, Cu, Zn, Sb, As) occur in high concentrations in the form of oxides and oxysalts. The studied amphiboles belong to six mineral species: magnesio-riebeckite, ferri-winchite, F-dominant analogue of ferri-winchite ("ferri-fluoro-winchite"), ferri-barroisite, ferri-nybøite, and a zinc-rich amphibole related to clino-suenoite. The main substitution schemes are Zn → Mg and Na + Fe3+ → Ca + Mg. The amphibole related to clino-suenoite has been studied in the most detailed way. Its empirical formula is (Mg2.99Zn2.47Mn1.26Fe3+0.30Ca0.07)Σ7.09(Si7.89Fe3+0.06Al0.05O22)(OH)2, and it is the most Zn-rich amphibole among those that have ever been described in literary sources. This amphibole is characterized by single-crystal and powder X-ray diffraction, IR spectroscopic and optical data. The role of high barium activity in the formation of sulfide-free ores of chalcophile elements has been substantiated. A possible mechanism of sulfur immobilization can be described by the scheme S2− + 2O2 ↔ SO42−; SO42− + Ba2+ → BaSO4↓. [ABSTRACT FROM AUTHOR]

The article provides information on new mineral discoveries as of July 2015. These include debattistiite, which was discovered in the Legenbach quarry in the Binn Valley, Valais, Switzerland, evdokimovite, which occurs as thin colorless needles with no twinning in association with markhininite and karpovite, and ferdowsiite, which is a gold-rich volcanogenic massive sulfide deposit of Cretaceous age.

The new mineral triazolite is found in a guano deposit located on the Pabellón de Pica Mountain, Iquique Province, Tarapacá Region, Chile. Associated minerals are salammoniac, halite, dittmarite, joanneumite, chanabayaite, nitratine, natroxalate and möhnite. Triazolite occurs as deep blue prismatic crystals up to 0.1 mm × 0.15 mm × 0.75 mm and their radial aggregates up to 1.5 mm across. The mineral is brittle. Its Mohs hardness is 2. D calc = 2.028 g cm–3. The infrared spectrum shows the presence of 1,2,4-triazolate anion and ammonia and water molecules. Triazolite is optically biaxial (–), α = 1.582(4), β = 1.625(3), γ = 1.625(3) and 2Vmeas = 5(3)°. The chemical composition (electron-microprobe data for Cl, Na, Fe and Cu; H, C, N and S contents were measured by gas chromatography of products of ignition at 1200°C; wt.%) is: Na 4.91, Fe 1.51, Cu 22.06, Cl 19.80, S 1.4, C 7.7, H 4.4, N 24.2, O (calc.) 12.83, total 98.81. The empirical formula is Na1.14(Cu1.86Fe0.14)(Cl2.99S0.23)N9.23C3.43H23.34O4.29. The idealized formula is NaCu2(N3C2H2)2(NH3)2Cl3·4H2O. Triazolite is a metalorganic ammine complex in which 1,2,4-triazolate anion and ammonia molecule are ligands coordinating Cu2+. The crystal structure was solved by direct methods and refined to R = 0.0242 based on 4210 unique reflections with I > 2σ(I). Triazolite is orthorhombic, space group P 212121, a = 19.3575(5), b = 7.15718(19), c = 12.5020(4) Å, V = 1732.09(8) Å3 and Z = 4. The eight strongest reflections of the powder X-ray diffraction pattern [ d , Å (I, %) (hkl)] are: 10.22 (97) (101), 6.135 (40) (011), 5.696 (17) (301), 5.182 (59) (202), 5.119 (100) (211), 4.854 (19) (400), 3.752 (16) (312, 501), 3.294 (18) (221). Triazolite is named for the presence of 1,2,4-triazolate anion. [ABSTRACT FROM AUTHOR]