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The new mckelveyite group mineral, alicewilsonite-(YLa), Na 2 Sr 2 YLa(CO 3) 6 ⋅ 3H 2 O, was found together with kamphaugite-(Y), paratooite-(Y), bastnäsite-(La), and decrespignyite-(Y) coating along fractures in dolomite at the Paratoo copper mine, South Australia, Australia. It occurs as pale pink to colourless pseudohexagonal tabular crystals up to 150 µ m in size. The streak is white; the lustre is vitreous. The mineral has no cleavage. Dcalc is 3.37 g cm -3. Alicewilsonite-(YLa) is optically biaxial (-), α = 1.556(2), β= 1.582(2), γ= 1.592(2), 2V (meas.) = 60(2)°, 2V (calc.) = 63° (589 nm). The IR spectrum is reported. The composition (wt %, average of seven analyses) is Na 2 O 7.43, CaO 2.00, SrO 18.43, BaO 1.64, Y 2 O 3 9.59, La 2 O 3 11.74, Pr 2 O 3 1.29, Nd 2 O 3 5.74, Sm 2 O 3 0.44, Eu 2 O 3 0.09, Gd 2 O 3 0.95, Dy 2 O 3 1.15, Ho 2 O 3 0.25, Er 2 O 3 0.89, Yb 2 O 3 0.29, CO 2 29.78, H 2 O 6.18, total 97.88. The empirical formula calculated on the basis of six cations with 3 H 2 O molecules is as follows: Na 2.10 Ca 0.31 Sr 1.56 Ba 0.10 Y 0.74 La 0.63 Pr 0.07 Nd 0.30 Sm 0.03 Eu 0.01 Gd 0.04 Dy 0.05 Ho 0.01 Er 0.04 Yb 0.01 (CO 3) 5.92 (H 2 O) 3. The mineral is triclinic, P 1, a= 8.9839(2), b= 8.9728(3), c= 6.7441(2) Å, α= 102.812(2)°, β= 116.424(2)°, γ= 60.128(2)°, and V= 422.17(2) Å 3 and Z= 1. The strongest reflections of the powder X-ray diffraction pattern [ d ,Å(I)(hkl)] are 6.03(43)(001), 4.355(100)(1 1‾ 0, 2‾1‾ 1, 120), 4.020(30)(1‾ 11, 210, 1‾2‾ 1), 3.188(29)(2‾1‾ 2, 1 1‾ 1, 121), 2.819(96)(002, 1‾ 12, 211, 1‾2‾ 2), 2.592(40)(3‾ 01, 030, 3‾3‾ 1), 2.228(33)(2‾ 21, 4‾2‾ 1, 2‾4‾ 1). 2.011(36)(2‾ 22, 003, 420, 2‾4‾ 2), 1.9671(32)(3‾ 03, 301, 0 3‾ 2, 032, 3‾3‾ 3, 331). The crystal structure was solved and refined from single-crystal X-ray diffraction data (R1= 0.058). [ABSTRACT FROM AUTHOR]

Microcline, KAlSi3O8 Along with quartz and albite, perthitic microcline is one of the dominant minerals in the pegmatites at Phnom Bayong. Late-stage hydrothermal quartz occurs in the pegmatites and miarolitic cavities as fine-grained (1-3-mm), translucent, white to yellow, euhedral, doubly terminated crystals on top of microcline and primary quartz. Multiple smaller tabular golden-white muscovite crystals to 6 mm form crusts on the larger muscovite crystals, feldspar, and quartz (fig. 16). Miarolitic Pegmatites The pegmatite mineralogy is dominated by quartz, microcline, albite (variety cleavelandite), two micas (zinnwaldite and muscovite), and chamosite. [Extracted from the article]

Joelbruggerite, ideally [Pb.sub.3][Zn.sub.3]([Sb.sup.5+], [Te.sup.6+])[As.sub.2][O.sub,13](OH,O), is a new arsenate mineral (IMA2008-034) and the [Sb.sup.5+] analog of dugganite, from the Black Pine mine, 14.5 km northwest of Philipsburg, Granite County, Montana. It is usually found perched on mimetite; other species that may be present include malachite, azurite, pseudomalachite, chalcocite, beudantite-corkite, duftite, dugganite, and kuksite, in milky quartz veins. Joelbruggerite occurs as barrel-shaped or prismatic crystals up to about 50 [micro]m across in various shades of purple. The crystals have an adamantine luster and a white streak. Mohs hardness is about 3. The fracture is irregular, and the tenacity is brittle. Joelbruggerite crystals are uniaxial (-), with a calculated refractive index of n = 1.993, and weakly pleochroic: X Y = gray, Z = purple; absorption: Z > X = Y. Crystals show straight extinction and are length-fast. The empirical chemical formula (mean of 5 electron microprobe analyses) calculated on the basis of 14 [O + OH] anions is [[Pb.sub.3.112]([Zn.sub.2.689][Fe.sup.2+.sub.0.185]).sub.[SIGMA]2.874] [([Sb.sup.5+.sub.0.650][Te.sup.6+.sub.0.451].sub.[SIGMA]1.101] [([As.sub.1.551][P.sub.0.203][Si.sub.0.160].sub.[SIGMA]1.914] [O.sub.13.335[(OH).sub.0.665]. Joelbruggerite is trigonal, space group P321, a = 8.4803(17),c 5.2334(12) [Angstrom], V= 325.94(12) [[Angstrom].sup.3], Z = 1. The five strongest lines in the powder X-ray diffraction pattern are [[d.sub.obs] in [Angstrom] (I) (hk/)]: 3.298 (100) ( 111 ), 3.008 (89) (021), 1.905 (39) (122, 131), 2.456 (36) (012, 121,030), and 1.609 (30) (112, 132, 231, 140). The crystal structure was solved from single-crystal X-ray diffraction data and refined to [R.sub.1] = 0.038 on the basis of 604 unique reflections with F > 4[sigma](F). It is composed of heteropolyhedral sheets of edge-sharing (Sb,Te)[O.sub.6] octahedra and Pb[O.sub.8] disphenoids, oriented parallel to (001). The sheets are cross-linked by As[O.sub.4] and Zn[O.sub.4] tetrahedra, which share comers to form an interlinked, two- and three- connected two-dimensional net parallel to (001). The mineral is named for JoEl Brugger (born 1967), Swiss-Australian mineralogist, for his contributions to mineralogy. Keywords: Joelbruggerite, new mineral, [Sb.sup.5+], arsenate, Black Pine mine, dugganite, crystal structure, bond valence

Thiospinels of Cu-(Fe) and platinum-group elements (PGE) are relatively abundant in the Kirakkajuppura PGE deposit of the Penikat layered complex, Finland. In actinolite-clinochlore rock that is nearly base-metal sulfide-free and relatively poor in chromite, the thiospinels occur as subhedral or anhedral grains (up to 0.4 mm). They are members of the cuprorhodsite-ferrorhodsite and cuprorhodsite-malanite series, relatively poor in cuproiridsite, and display considerable grain-to-grain variations in Cu, Fe, Pt, and Rh. Strong negative Fe-Cu, Pt(+Ir)-Fe, Rh-Cu, and Rh-Pt and strong positive Pt(+Ir)-Cu and Rh-Fe correlations in these thiospinels are indicative of a coupled substitution: Fe-for-Cu substitution in the tetrahedral (A) sites causes an excess in formal positive charge, which is compensated by Rh-for-(Pt+Ir) substitution in the octahedral (B) sites. Probable valence states in the Fe-free and Fe-rich end-members of the solid-solution series at Penikat are [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII] and [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII], and these suggest the heterovalent substitution scheme [sup.A][Fe.sup.3+] + 2 [sup.B][Rh.sup.3+] [right arrow] [sup.A][Cu.sup.+] + 2 [sup.B][Pt.sup.4+](+2 [Ir.sup.4+]) to incorporate Fe in the ferrorhodsite-rich end member.

A sample of Sb-rich segnitite from the Black Pine mine, Montana, U.S.A., has been studied by microprobe analyses, single-crystal X-ray diffraction, and μ-EXAFS and XANES spectroscopy. Linear combination fitting of the spectroscopic data provided Sb5+:Sb3+ = 85(2):15(2), where Sb5+ is in octahedral coordination substituting for Fe3+ and Sb3+ is in tetrahedral coordination substituting for As5+. Based upon this Sb5+:Sb3+ ratio, the microprobe analyses yielded the empirical formula Pb1.02 H1.02(Fe3+2.36Sb5+0.41Cu2+0.27)Σ3.04(As5+1.78Sb3+0.07S6+0.02)Σ1.88O8(OH)6.00. The crystal structure refinement and bond valence analysis are consistent with these cation site assignments. The formation of Sb-rich segnitite opens new possibilities for Sb sinks within the supergene zone. Segnitite may, in fact, be an ideal host for the sequestering of several toxic elements for pH < 2. At higher pH values, As is more likely to be incorporated into schwertmannite and ferrihydrite. [ABSTRACT FROM AUTHOR]

A combination of techniques, including powder X-ray diffraction (XRD), electron microprobe analysis (EPMA), transmission electron microscopy (TEM), and X-ray absorption spectroscopy (XAFS), is used to characterize the common ferric-arsenate-sulfate compounds, which could result from the pressure oxidation of refractory gold ores at elevated temperatures. Three general types of precipitate are identified; namely, arsenate-bearing basic ferric sulfate [FeSO4(OH) and designated as BFS], ferric arsenate-sulfate [an extensive solid solution Fe(AsO4)0.2-0.7(SO4)0.7-0.2(OH)0.7-0.2 and designated as FAS], and hydrated ferric orthoarsenate (FeAsO4·0.75H2O). The crystal structure of FAS is solved by precession electron-diffraction experiments. The structures of BFS and FAS are constructed from octahedral Fe3+ chains, which are cross-linked by sulfate and arsenate tetrahedra. Extensive substitution of arsenate for sulfate occurs in both types of compounds with charge neutrality being maintained by variations in the (OH) content. The XAFS spectra indicate that the local structures of both BFS and FAS are made of corner-linked single chains of FeO6 octahedra where the chains are linked by AsO4 or SO4 tetrahedra forming alternating layers of FeO6 octahedra and AsO4 or SO4 tetrahedra. Preliminary toxicity characteristics leaching procedure (TCLP) testing of the precipitates indicates that FAS with a molar ratio As/(As+S) ratio of ≥0.5 could be an acceptable material for disposal in a tailings impoundment, whereas more As-rich FAS and BFS may require further treatment. The results for the laboratory-prepared precipitates are compared with those obtained on three residues from the process- ing of refractory gold ores. The major As-carrier in one of the residues is FAS, whereas As-bearing goethite and hematite are the dominant As-carriers in the other two residues. Thus, the mineralogical characteristics of the residues dictate the appropriate arsenic management and disposal options in the processing of refractory gold ores. [ABSTRACT FROM AUTHOR]

The article offers information on new mineral names. Afmite is a mineral found at Fumade, Castelnaue-de-Brassac, Tarn, France that is rarely associated with aluminum-phosphates matulaite. Hydroniumpharmacosiderite was described from a crystal identified as potassium-deficient pharmacosiderite. Kerimasite is a new zirconium garnet from the Kerimasi nephelinite/carbonatite volcano and Loluni.

The article offers information on names of new mineral that has been approved by the International Minerological Association Commission on New Minerals and Mineral Names (IMA CNMMN). These include Adranosite discovered in pyroclastic breccia of La Fossa crater, Vulcano in Italy, Arisite-(Ce) rare-earth fluorcarbonate from Quebec, Canada and from Aris phonolite in Namibia and Arsenoflorencite-(La) from Komi, Republic, Russian Federation. It also notes new minerals including Carbobystrite from Kola Peninsula, Russia and Dantopaite from Erzwies, Austria.

This article provides information on new minerals. Cámaraite is a mineral from the Verkhnee Espe rare-element deposit located at the noerthern exo-contact of the Akjailyautas granite massif in Tarbagatai mountain range in Kazakhstan. Daliranite came from a mineral deposit in Takab in West Azarbaijan Province, Iran.

This study was undertaken to characterize the mineral paragenesis and metal zoning at the property scale, evaluate the potential sources of ore-related metals, quantify the relationship between intensity of alteration and gold grade, and propose a comprehensive genetic model for the Carlin-type Au deposits at the southern part of the Goldstrike property, Nevada. Mineralogy, textural relationships, whole-rock composition, and spatial distribution of the studied samples revealed two types of gold ore: Ore I and II. The former, which is hosted by the Roberts Mountains and Rodeo Creek Formations, and the Wispy, Planar, and Upper Mud units of the Popovich Formation, is the most abundant and widespread in the property. Ore I is characterized by intense hydrothermal alteration (e.g., carbonate dissolution, silicification, and precipitation of pyrite) and high amounts of trace elements (e.g., Ag, As, Au, Ba, Cd, Cu, Hg, Mo, Ni, S, Sb, Se, Te, Tl, and Zn). On the other band, Ore II, which is hosted in the Wispy, Planar, and Soft Sediment Deformation units of the Popovich Formation, is mainly confined to the central-north-northwest portion of the Screamer deposit and is weakly altered with low concentration of trace elements. Both Ores I and II contain similar average concentrations of Au in whole rock (14 and 19 g/t Au, respectively) and in pyrite (290 and 540 ppm, respectively); however, auriferous pyrite from Ore I has higher trace element (As, Ag, Cu, Hg, Ni, Sb, Se, and Tl)/Au ratios than Ore II. The sedimentary units are interpreted to be the major local source of Cd, Mo, Ni, U, V, and Zn and minor As, Cu, Hg, and Se as denoted by the composition of least altered samples and diagenetic pyrite and sphalerite. This study reveals that Al2O3 and TiO2 are the most immobile compounds, and their distribution indicates a homogeneous source for the detrital components in the sedimentary rocks. Among the ore-related trace elements, Tl best correlates with Au grade (R² = 0.69) and shows some relationship with the calculated amount of pyrite (R² = 0.49), indicating that Tl would be the best element to vector toward zones of high-glade Carlin-type Au mineralization. Gold grades do not correlate with the amount of pyrite, degree of alteration, or organic C. Our results integrated with available thermodynamic data for Au, ore-related elements, and SiO2 lead us to suggest that the formation of Ore I occurred more proximal to the major mineralizing conduits as the hot, more acid, SiO2- and trace element-rich auriferous fluids interacted with Fe-bearing impure carbonate host rocks, intensely dissolving the carbonate rocks and precipitating quartz and auriferous pyrite in the Betze-Post and Rodeo deposits. As the fluids moved laterally throughout the favorable host rocks, the pH increased, leading to a decreasing in the rate of carbonate dissolution and in the solubility of silica, favoring the formation of more distal Ore II in the central-northern part of the Screamer deposit. Significantly, the gold concentrations in whole rock and in pyrite are, in some way, very similar in both ore types, being slightly higher in Ore II, suggesting that less acidic conditions were still favorable for the incorporation of gold in the structure of pyrite, even at lower concentrations of other trace elements. [ABSTRACT FROM AUTHOR]

Auriacusite, ideally Fe3+Cu2+AsO4O, is a new arsenate mineral (IMA2009–037) and the Fe3+ analogue of olivenite, from the Black Pine mine, 14.5 km NW of Philipsburg, Granite Co., Montana, USA. It occurs lining quartz vughs and coating quartz crystals and is associated with segnitite, brochantite, malachite, tetrahedrite and pyrite. Auriacusite forms fibrous crystals up to about 5 µm in width and up to about 100 µm in length, which are intergrown to form fibrous mats. Individual crystals are a brownish golden yellow, whilst the fibrous mats are ochreous yellow. The crystals have a silky lustre and a brownish yellow streak. Mohs hardness is about 3 (estimated). The fracture is irregular and the tenacity is brittle. Auriacusite crystals are biaxial (+), with α = 1.830(5), β = 1.865(5) and γ = 1.910(5), measured using white light, and with 2 Vmeas. = 83(3)º and 2 Vcalc. = 84.6º. Orientation: X = a, Y = c, Z = b. Crystals are nonpleochroic or too weakly so to be observed. The empirical formula (based on 5 O atoms) is (FeCu0.85Zn0.03)Σ2.21(As0.51Sb0.27Si0.04 S0.02Te0.01)Σ0.85O5. Auriacusite is orthorhombic, space group Pnnm, a = 8.6235(7), b = 8.2757(7), c = 5.9501(5) Å, V = 424.63(6) Å3, Z = 4. The five strongest lines in the powder X-ray diffraction pattern are [ dobs in Å / ( I) / hkl]: 4.884 / (100) / 101, 001; 2.991 / (92) / 220; 2.476 / (85) / 311; 2.416 / (83) / 022; 2.669 / (74) / 221. The crystal structure was solved from single-crystal X-ray diffraction data utilising synchrotron radiation and refined to R1 = 0.1010 on the basis of 951 unique reflections with Fo > 4σ F. Auriacusite is identified as a member of the olivenite group with Fe3+ replacing Zn2+ or Cu2+ in trigonal bipyramidal coordination. Evidence suggests that auriacusite is an intermediate member between olivenite and an as yet undescribed Fe3+Fe3+-dominant member. The name is derived from the Latin auri (golden yellow) and acus (needle), in reference to its colour and crystal morphology. [ABSTRACT FROM AUTHOR]

The article offers information on the discovery of new minerals and its names. One of which is the Brumadoite, a mineral named after the locality of Brumado, Bahia Brazil and it microcrystalline aggregates on, and as psuedomorphs after magnesite. Another one is the Burgessite which was discovered and collected from Keeley mine in Timiskaming District, Ontario. Moreover, the Bussyite-(Ce) was found in Mont Saint Hilaire, Rouville County, Quebec.

The article presents abstracts on mineralogy, including crystal structure of alloriite, the discovery of hephaistosite mineral and the discovery of labyrinthite as a new member eudialyte group.

The article presents a study concerning the chemical analysis on the discovery of new minerals by using an electron microprobe. These minerals include the calvertite, chukanovite, ferroskutterudite and hingannite. Calvertite was discovered during the examination another new mineral gallobeaudanite from the Tsumeb mine, and it found that the small unit cell and the stable character of calvertite is a metastable, highly disordered mineral. The chukanovite is the product of terrestrial alteration found in cavities in the Dronino meteorite, an ataxite iron meteorite consisting of kamacite and minor amounts of taenite and chromite. Moreover, it is indicated that a single-crystal X-ray refinement of hingannite was not possible due to the small size of the crystals.

The article presents information on several new mineral names. They include ardennite-(V) found in a specimen of piemontite-bearing mica schist and occurs only in one thin quartzitic layer in the studied specimens. Georgbarsanovite came from boulders of nepheline-feldspar pegmatite in the upper reaches of the Petreliusa River valley, Khibiny alkaline massif, Kola Peninsula, Russia. The mineral consists of 1-2 centimeter thick branching veinlets in the brown eudialyte. Jadaite is a lithium sodium borosilicate mineral discovered in Jadar Basin, Serbia.