... in relationship to ore formation are still not well understood, especially for the important case of fluoride-rich greisen. Here, we investigate the sequence and formation mechanism of the topaz-greisen in the Zinnwald/Cínovec deposit. Based on the mineral abundances, the alteration profile can be divided...

... on understanding crystallographic controls on gas/mineral partitioning. This work investigates the structural accommodation of As, Mn, Ga, Ge, Fe, and Ti in vapor-deposited topaz of vesicular topaz rhyolite from the Thomas Range, Utah, through single-crystal synchrotron microbeam X-ray techniques on picogram...

... of America Fluorine amphibole Climax-type Mo deposits topaz rhyolite xenolith southern Rocky Mountains ultrahigh temperature metamorphism granulite Experimental Halogens in Honor of Jim Webster Fluorine-rich granites and rhyolites are often associated with economic mineral deposits of Sn...

...Kako Aradachi; Morihisa Hamada; Kiyoshi Tsuge; Tohru Watanabe Abstract Topaz, Al 2 SiO 4 (OH) x F (2– x ) , may play a significant role in transporting water and fluorine into the Earth’s interior at subduction zones. Seismological detection of topaz gives us insights into the transport mechanisms...

... and in beryl from the Morrua Mine, both in the Alto Ligonha District, Mozambique, and a calcite-group carbonate and whewellite [CaC 2 O 4 ∙H 2 O] in fluid inclusions in topaz from Khoroshiv, Ukraine. The occurrence of oxalate is interpreted to be due to a reaction of some form of carbon (possibly CO or bitumen...

...Peter J. Pollard Abstract The Yichun Ta-Sn-Li deposit occurs within the 9.5-km 2 Yashan Igneous Complex, which is made up of felsic, peraluminous intrusions including two-mica, Li-mica, and topaz-lepidolite granites. The topaz-lepidolite granite forms a thin sheet confined to the upper part...

.... The results also indicated that zoning is better retained in larger grains ( i.e ., > 500 × 500 μm) with minimal alteration and mineral inclusions. An exceptionally well-zoned Li-rich siderophyllite from the Pleasant Ridge topaz granite in southwestern New Brunswick shows Ti, Ta, Sn, W, Cs, Rb, and V...

...Earl F. O'Bannon, III; Quentin Williams Abstract Topaz [Al 2 SiO 4 (F,OH) 2 ] is a subduction-related mineral that is found in metasediments and has a large pressure and temperature stability field. Here, we use luminescence spectroscopy of Cr 3+ to probe the Al site in topaz at pressures up to ~60...

...Donald A. Dallaire; James W. Nizamoff §   E-mail address : [email protected] *  E-mail address : [email protected] © 2019 Mineralogical Association of Canada 2019 topaz Conway granites miarolitic cavities White Mountain Igneous Province South Baldface...

... for later low-temperature hydrothermal processes, which further enriched the Be in the underlying tuff (up to 3000 ppm; Bikun 1980 ; Foley et al. 2012 ) as discussed below. The Spor Mountain rhyolite is a topaz rhyolite; these A-type rhyolites are typically enriched in fluorine (>0.2 wt...

...Teodoro Gauzzi; Leonardo Martins Graça; Leonardo Lagoeiro; Isolda De Castro Mendes; Gláucia Nascimento Queiroga ABSTRACT A study of the cathodoluminescence (CL) properties of imperial topaz from Ouro Preto region (Minas Gerais state, Brazil) and its relation with trace-element composition...

... intersecting highly fractionated, topaz–zinnwaldite S-type leucogranite. Fluorarrojadite-(BaNa) is associated with fluorapatite, ‘fluordickinsonite-(BaNa)’, triplite, viitaniemiite and minor amounts of other minerals. It forms fine-grained irregular aggregates up to 4 cm x 2 cm, which consist of individual...

... concentrations. The granites exhibit a light pink colour and contain mainly albite, quartz, muscovite, lithian muscovite, and lepidolite, with minor amounts of amblygonite–montebrasite, herderite, fluorapatite, topaz, and cassiterite, as well as accessory beryl and goyazite. Electron microprobe analyses...

...Gianfranco Ulian; Giovanni Valdrè Abstract In this work, we modeled the structure, the compressional behavior and the physical properties of topaz over six different fluorine contents and a wide range of pressure, using a quantum mechanical approach based on periodic boundary conditions. We adopted...

... using electron probe microanalyses. Zircons from the biotite and tourmaline granites are poor in minor and trace elements, usually containing 1.0–1.5 wt.% HfO 2 , <0.5 wt.% UO 2 and P 2 O 5 , <0.25 wt.% Y 2 O 3 , <0.2 wt.% Sc 2 O 3 and Bi 2 O 3 and <0.1 wt.% ThO 2 . Zircon from topaz...

...Andrea Agangi; Arnold Gucsik; Hirotsugu Nishido; Kiyotaka Ninagawa; Vadim S. Kamenetsky Abstract In order to define the cathodoluminescence (CL) properties of magmatic topaz and its relation with trace-element composition, we studied topaz phenocrysts from the Ary-Bulak ongonite massif, Russia...

... (Sek-II) occur in a blocky unit. Sek-II is partly replaced by biotite, muscovite, chlorite, schorl, and minor to trace zinnwaldite, beryl, albite, fluorapatite, calcite, topaz, and several accessory Nb,Ta,Ti-oxides and sulfides, and late smectite. Rather heterogeneous Sek-II (Sek 71–75 MnCrd 23–28 Crd...