 | | Journal (article/letter/editorial) | | (Northern Espinhaço, Brazil): LA-ICP-MS age determinations on relict and recrystallized zircon and geodynamic...(Northern Espinhaço, Brazil): LA-ICP-MS age determinations on relict and recrystallized zircon and geodynamic...range at 643±19 Ma. - Metamorphic zircon forms from protolith-zircon in a dissolution- - ip t precipitation...metamorphic overprinting of a psammitic rock 2. Zircon crystals can be replaced completely or can be preserved...preserved ip t completely 3. Local differences in zircon and/or fluid composition decide cr 4. Age of |  | | Journal (article/letter/editorial) | | metaquartzites of the northern Serra do Espinhac o (State of Bahia, Brazil) G. Morteani1 and D. Ackermand2...horizon belongs to the Middle Proterozoic Serra de Vereda member of the S~ao Marcos Formation of the...hills of the Serra de Canas=Cana Brava (Northern Serra do Espinhac o, State of Bahia, NE Brazil) about 10...10 km west of the town of Boquira. Sky blue lazulite and deep blue to lilac dumortierite are enriched...controlled by the amount of xenotime, monazite and zircon. Oxygen thermometry on quartz and hematite and |  | Visser, D., Felius, R. O., Moree, M. (1997) Augelite and cerian crandallite in dumortierite quartzites, Vaca Morta quarry, Vereda range, Macaúbas, Bahia, Brazil. Mineralogical Magazine, 61 (407) 607-609 doi:10.1180/minmag.1997.061.407.11 | Journal (article/letter/editorial) | | dumortierite quartzites, Vaca Morta quarry, Vereda range, Macatibas, Bahia, Brazil D. Visser University...quartzites from the Vaca Morta Quarry, Yereda range, Macatibas, Bahia, Brazil. The Vereda range in the northwest...northwest of the state of Bahia is well known for the occurrence of dumortierite quartzites (Cassedanne...kyanite, crandallite, augelite, hematite, futile and zircon. The rock shows a distinct microscopic layering...orientated randomly. However, other samples from the quarry show a distinct foliation made up by muscovite |  | | Journal (article/letter/editorial) | | muscovite and dumortierite with the minor constituents zircon, monazite and xenotime in addition to quartz are...have been described e. g. from the Serra do Espinhaço (Bahia, Brazil, Casse- danne & Franco 1966, Cassedanne...Visser et al. 1997), from Diamantina (Minas Gerais, Brazil, Horn et al. 1996, Morteani & Ackermand 2001),...depositional age of 1800 Ma is consistent with the zircon ages of 1850 and 2500 Ma, stromatolite characteristics...rocks were metamorphosed between 536 ± 1 Ma (U – Pb zircon age) and 523 ± 2 Ma (U – Pb titanite age). All |  | | Journal (article/letter/editorial) | | kyanite, And = andalusite, Ms = muscovite, Zrn = zircon, Mnz = monazite, Xtm = xenotime, Lzl = lazuilite...quartz, plagioclase, biotite and accessories such as zircon, titanite, apatite and allanite. The garnet-bearing...feldspar, biotite, muscovite and garnet. Apatite, zircon, monazite-(Ce) and allanite are accessory. Most...various inclusions of Kfeldspar, gedrite, magnetite, zircon, apatite, monazite-(Ce), allanite and quartz. Garnets...relict K-feldspar and accessory minerals, such as zircon and apatite. The rocks are fine-grained and have |  | | Journal (issue) | | synthetic moissanite 386 Gem Notes Large kunzite from Brazil| Marble-hosted ruby mine, Mogok, Myanmar|Secondary...from Brazil|Quartz sphere with large inclusion|Zawadi sapphires|Tourmaline from the Havey quarry, Maine...Maine, USA| Greenland tugtupite|Orange zircon from Myanmar|Glass imitation of emerald|Large black synthetic...Kunzite Gem Crystal from Brazil The granitic pegmatites of Minas Gerais, Brazil, are well known for producing...was mined in 1998 from the Urucum pegmatite in Brazil. Photo by B. M. Laurs. (1962, p. 287) also reported |  | | Journal (issue) | | Trace-element Composition of Paraíba-type Tourmaline from Brazil, Mozambique and Nigeria By Martin Okrusch, Andreas...cushion and ~5 ct stone in ring) and from Paraíba, Brazil (3.5 mm gems in bracelet and 4.02 ct oval). Courtesy...Leonardo Silva Souto (Gems in Gems, Teófilo Otoni, Brazil) had approximately 50 cabochons weighing up to...recently had the opportunity to investigate the age of zircon inclusions in faceted blue sapphires from the Mogok...weighing 26 and 11 ct (Figure 14) by analysing the zircon inclusions exposed at their girdles. The zircons |  | | Journal (issue) | | / Chuong Tran Cong Quan Cenozoic sediment Bai Da Lan Mong Son Yen Thai Khe Nhan Nui Chua complex...EDS with SEM. These included titanite, rutile, zircon, graphite, apatite, several sulfide minerals (again...ite crystals, SEM imaging revealed inclusions of zircon and pargasite. Therefore, titanite probably represents...Spinel-titanoclinohumite association from a marble quarry near Rajapalaiyam area, part of the 550 Ma of southern...obtained exclusive rights to the mine (an open quarry, in accordance with Moroccan law). The company |
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