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Ametista do Sul Brazil

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Journal Article
Published: 01 July 2007
Geological Magazine (2007) 144 (4): 731–739.
...DOMINIQUE PROUST; CLAUDE FONTAINE Abstract The amethyst geodes observed in the tholeiitic basaltic flow from the Triz quarry at Ametista do Sul (Rio Grande do Sul, Brazil) show particular wall-layering infillings with, from the outside inwards, celadonite, chalcedony, fine-grained quartz and large...
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Journal Article
Published: 19 July 2010
Geological Magazine (2010) 147 (6): 954–970.
... do depósito de ágata e ametista do depósito Novo São João, Santana do Livramento, RS. MS thesis, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil (in Portuguese). Internet: www.lume.ufrgs.br/bitstream/handle/10183/12017/000620019.pdf?sequence=1 . Bellieni G. , Comin...
Journal Article
Published: 01 January 2007
Geological Magazine (2007) 144 (1): 53–65.
...DOMINIQUE PROUST; CLAUDE FONTAINE Abstract Size distribution data obtained from detailed field study of bubbles and amethyst-geodes in the basaltic lava flows of the Serra Geral Formation (Ametista do Sul, Rio Grande do Sul, Brazil) are used in cooling and vesiculation models to infer the origin...
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Journal Article
Published: 30 November 2019
The Canadian Mineralogist (2019) 57 (6): 867–883.
... do Sul, Brazil ( Fig. 1 ), the concentric and horizontal bands are composed entirely of various textural and mineralogical types of silica minerals. The patches of late opalization (bluish color) contain very thin-fibered aggregates of cristobalite and chalcedony. In the portion showing onyx banding...
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Journal Article
Published: 01 December 2010
The Canadian Mineralogist (2010) 48 (6): 1533–1568.
... in that they are vesicle poor, and they do not feed upward into sheets, as do vesicle cylinders. The field relationships are first discussed, followed by the petrographic features of the pipes. TABLE 1. REPRESENTATIVE COMPOSITIONS OF MESOSTASIS MATERIAL, NORTH MOUNTAIN BASALT, NOVA SCOTIA...
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Journal Article
Published: 01 October 2017
Mineralogical Magazine (2017) 81 (5): 1223–1244.
... Agate, andesite, 1,12,13,15,17 Las Choyas, Mexico (JC,BC) 45 Liebres Formation, vitric tuff, 6,9,11,15,17 Mt. Somers, New Zealand (VT) 89 Woolshed Creek, basalt, 12,13,14,17,18 Rum, Scotland (RL) 60 Northern Rum, basalt, 1,2,3,12,13 Rio Grande do Sul Brazil & UK purchase 135...
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Journal Article
Published: 01 May 2016
European Journal of Mineralogy (2016) 28 (2): 295–311.
... particles of garnierite samples from the Morro do Niquel (Brazil). The conversion of serpentine into TL minerals appears to be limited in the first infilling (particularly in the white ‘deweylite’), whereas it is almost completed in the second one. In some fault zones of the New Caledonian peridotites...
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Journal Article
Published: 01 April 2013
Mineralogical Magazine (2013) 77 (3): 227–248.
... even though the overall pattern is commonly misshapen. A second type of banding with apparently geopetal horizontal bands is less common. In many agate-producing regions, these horizontally banded agates are unknown; but they are widespread in other areas (e.g. Rio Grande do Sul, Brazil; Agate Creek...
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Journal Article
Published: 01 March 2004
European Journal of Mineralogy (2004) 16 (2): 269–278.
.... , Kostitsyn , Y. , Preinfalk , C. , Gatter , I. , Streider , A.J. ( 2002 ) Genesis of amethyst geodes in basaltic rocks of the Serra Geral Formation (Ametista do Sul, Rio Grande do Sul, Brazil): a fluid inclusion, REE, oxygen, carbon, and Sr isotope study on basalt, quartz, and calcite...
FIGURES
Journal Article
Published: 01 August 2009
Mineralogical Magazine (2009) 73 (4): 551–568.
... . Gilg , H.A. , Morteani , G. , Kostitsyn , Y. , Preinfalk , C. , Gatter , I. and Streider , A.J. ( 2003 ) Genesis of amethyst geodes in basaltic rocks of the Serra Geral Formation (Ametista do Sul, Rio Grande do Sul, Brazil): a fluid inclusion, REE, oxygen, carbon, and Sr...
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Journal Article
Published: 01 August 2012
American Mineralogist (2012) 97 (8-9): 1284–1290.
... Minerals , 32 , 153 – 179 . Gilg H. Morteani G. Kostitsyn Y. Preinfalk C. Gatter I. Strieder A. ( 2003 ) Genesis of amethyst geodes in basaltic rocks of the Serra Geral Formation (Ametista do Sul, Rio Grande do Sul, Brazil): a fluid inclusion, REE, oxygen, carbon, and Sr...
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Journal Article
Journal: Economic Geology
Published: 01 January 2004
Economic Geology (2004) 99 (1): 203–217.
... OF VOLCANOLOGY Springer-Verlag New York Inc., Journal Fulfillment, P.O. Box 2485, Secaucus, NJ 07096-2485 CANADIAN JOURNAL OF EARTH SCIENCES Economic Geology 2004 E conomic G eology prints partial tables of contents of a number of journals as an information service. Please do not write...
Journal Article
Published: 01 March 2010
European Journal of Mineralogy (2010) 22 (2): 215–234.
..., massive or vein deposits. Most of the secondary mineral phases are clay minerals, zeolites and carbonates formed by pervasive alteration, and localized vapour-phase deposition in vesicles and geodes. Amongst extensive basaltic lava piles around the world in Scotland, Iceland, Brazil, Namibia, Columbia...
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Journal Article
Published: 01 July 2017
The Canadian Mineralogist (2017) 55 (4): 701–723.
... ), microthermometric experiments ( Spencer et al . 1992 ), and oxygen-isotope measurements ( Rondeau et al . 2004 ). Gem opal is found mostly in acidic volcanoclastic host-rocks ( e.g ., Mexico, Honduras, Brazil, many places in the western U.S.A., Slovakia). In Australia, the volcanic source is strongly re-worked...
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Journal Article
Published: 19 December 2017
Journal of Sedimentary Research (2017) 87 (12): 1314–1335.
... prospectivity in similar settings (e.g., inter-basalt and sub-basalt sediments in the Faroe–Shetland Basin, Rockall Trough, and inter-basalt sediments offshore Southern Atlantic, e.g., Brazil, Angola, and Namibia, as well as early volcanic sequences in flood basalts and volcanic margins globally...
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