 | Giuliani, Gaston, Fallick, Anthony, Rakotondrazafy, Michel, Ohnenstetter, Daniel, Andriamamonjy, Alfred, Ralantoarison, ThĆ©ogĆØne, Rakotosamizanany, Saholy, Razanatseheno, Marie, Offant, Yohann, Garnier, Virginie, Dunaigre, Christian, Schwarz, Dietmar, Mercier, Alain, Ratrimo, Voahangy, Ralison, Bruno (2007) Oxygen isotope systematics of gem corundum deposits in Madagascar: relevance for their geological origin. Mineralium Deposita, 42 (3) 251-270 doi:10.1007/s00126-006-0105-3 | Journal (article/letter/editorial) | | isotope systematics of gem corundum deposits in Madagascar: relevance for their geological origin Gaston...dāAntananarivo, Ambohitsaina, BP 906, Antananarivo 101, Madagascar Y. Offant Cerege, Europole MĆ©diterranĆ©en de lāArbois...Ambaranjana Antanimora, Antananarivo 101, Madagascar ces in Madagascar to provide a gemstone geological identification...characterization. Primary corundum deposits in Madagascar are hosted in magmatic (syenite and alkali basalt)...xenoliths contained in the alkali basalt of Soamiakatra have Ī“18O values ranging between 1.3 and 4.7ā° |  | Giuliani, Gaston, Groat, Lee, Fallick, Anthony, Pignatelli, Isabella, Pardieu, Vincent (2020) Ruby Deposits: A Review and Geological Classification. Minerals, 10 (7) 597 doi:10.3390/min10070597 | Journal (article/letter/editorial) | | presence of ruby: (1) amphibolite to medium pressure granulite facies metamorphic belts and (2) alkaline basaltic...of formation: (Type I) magmatic-related and (Type II) metamorphic-related. Type I is characterized by...magmatic) origin are hosted by alkali basalts (Madagascar and others), and Type IB corresponding to xenocrysts...in kimberlite (Democratic Republic of Congo). Type II also has two sub-types; metamorphic deposits sensu...stricto (Type IIA) that formed in amphibolite to granulite facies environments, and metamorphic-metasomatic |  | | Book | | and kimberlite (IB) hosts. Metamorphic rocks (Type II) are subdivided into Metamorphic, sensu stricto,...Tanzania; Andilamena/Zahmena and Ampanihy/Toliara, Madagascar. Marble-ruby types included various deposits...sapphire deposits included Andilamena and Andrebabe, Madagascar; various Mogo Gem Tract sites, Myanmar; Elahera...Namehaca, Mozambique and Ampanihy and Zahmena, Madagascar. In contrast, Appaluttoq ruby, Greenland, 4...ļ¬elds and schematic Greenschist, Amphibolite and Granulite ļ¬elds. The RbāSr isotope, UāPb rutile Concordia |  | Wang, Kandy, Graham, Ian, Martin, Laure, Voudouris, Panagiotis, Giuliani, Gaston, Lay, Angela, Harris, Stephen, Fallick, Anthony (2019) Fingerprinting Paranesti Rubies through Oxygen Isotopes. Minerals, 9 (2) 91 doi:10.3390/min9020091 | Journal (article/letter/editorial) | | Russia and sapphire from a secondary deposit in Madagascar. Table 4 lists the global low to ultra-low oxygen...oxygen isotope analyses for corundums. The Madagascar sapphire deposit of Ilakaka with Ī“18 O of ā0.3h...30] and one instance of ruby from the Soamiakatra area of Madagascar [26]. The Karelia corundum formed under...distinguished from the Paranesti rubies. The Madagascar rubies show much higher average Ī“18 O values...corundums with low oxygen isotope values. Country District Ī“18 Oh (Min) Paranesti-1 * 0.65 Greece 1 Paranesti-5 |  | | Journal (article/letter/editorial) | | East African rift (Krzemnicki et al. 1996), in Madagascar (Schwarz et al. 2000; Giuliani et al. 2007a)...metamorphic rocks, ranging from greenschist to granulite facies, and granites which are found as xenoliths...amphibolite of Peygerolles in the Haut Allier granulite gave a Ī“18O of 5.0ā° (Table 1). This oxygen isotopic...Thailand (Sutthirat et al. 2001) or at Soamiakatra, Madagascar (Rakotosamizanany 2003). Rubies are generally...area such as in Cambodia (Pailin), Madagascar (Antanifotsy-Soamiakatra), Australia (Yarrowitch), and Thailand |  | | Journal (article/letter/editorial) | | amphibolite-facies temperatures and pressures, reaching granulite facies conditions near the village of FiskenƦsset...B 60 80 20 20 80 40 60 60 40 60 20 Soamiakatra Ilakaka Andilamena Pailin (P) Pailin (C) Bo Rai...is found with samples from Soamiakatra, Ilakaka, and Andilamena in Madagascar, Bo Rai and Chanthaburi in...and Ilakaka in Madagascar and gem-corundum in a cordieritite from Iankaroka, Madagascar have lower reported...with high fluid activity (like the biotitites in Madagascar). The low Ī“18O values are a potentially useful |  | Garnier, V., Ohnenstetter, D., Giuliani, G., Fallick, A. E., Phan Trong, T., HoĆ ng Quang, V., Pham Van, L., Schwarz, D. (2005) Basalt petrology, zircon ages and sapphire genesis from Dak Nong, southern Vietnam. Mineralogical Magazine, 69 (1) 21-38 doi:10.1180/0026461056910233 | Journal (article/letter/editorial) | | erosional deposits in southeast Asia, Australia and Madagascar. The basalt Ā®elds yielding corundums are widespread...deposits of Dak Nong. The Dak Nong sapphire-mining district lies in the Dak Lak Province near the Cambodian...rocks sampled from basaltic ĀÆows from the mining district of Dak Nong. Chemical analyses for the samples...suite Tholeiitic basalt suite Subgroup I Subgroup II Sample V75b V75f V75g V75h V75e V74a V74c...On the spider diagram (Fig. 5c,d), the sub-group II is enriched in REE compared to the sub-group I which |  | Voudouris, Panagiotis, Mavrogonatos, Constantinos, Graham, Ian, Giuliani, Gaston, Melfos, Vasilios, Karampelas, Stefanos, Karantoni, Vilelmini, Wang, Kandy, Tarantola, Alexandre, Zaw, Khin, Meffre, Sebastien, Klemme, Stephan, Berndt, Jasper, Heidrich, Stefanie, Zaccarini, Federica, Fallick, Anthony, Tsortanidis, Maria, Lampridis, Andreas (2019) Gem Corundum Deposits of Greece: Geology, Mineralogy and Genesis. Minerals, 9 (1) 49 doi:10.3390/min9010049 | Journal (article/letter/editorial) | | the Pan-African orogeny are present in southern Madagascar, East Africa, South India and Sri Lanka; those...sapphires occur in Australia, northern and central Madagascar, Nigeria, Cameroon, French Massif Central and...including UHP-eclogitic metamorphism, followed by HP granulite-facies, amphibolite-facies and finally by greenschist...diaspore; 420 to 500 ā¦ C (appearance of biotite) for zone II; 500 ā¦ C to 540ā580 ā¦ C (disappearance of chloritoid)...metamorphism; (ii) syn-metamorphism depletion in O related to hydration subduction and metamorphism; (ii) syn-metamorphism |  | Keulen, Nynke, Thomsen, Tonny B., Schumacher, John C., Poulsen, Majken D., Kalvig, Per, Vennemann, Torsten, Salimi, Rita (2020) Formation, origin and geographic typing of corundum (ruby and pink sapphire) from the FiskenƦsset complex, Greenland. Lithos, 366. 105536pp. doi:10.1016/j.lithos.2020.105536 | Journal (article/letter/editorial) | | village of FiskenƦsset was metamorphosed at lower granulite-facies conditions, whereas farther to the south...conditions of the upper-amphibolite to lower-granulite facies. Various combinations of the following...regional metamorphic geology (amphibolite-facies to granulite-facies conditions). For purposes of comparison...complexes like dunites and typically forms at granulite-facies conditions, commonly with sapphirine as...with ultramafic complexes that were hydrated at granulite-facies conditions. Even though we agree with this |  | Graham, Ian, Sutherland, Lin, Zaw, Khin, Nechaev, Victor, Khanchuk, Alexander (2008) Advances in our understanding of the gem corundum deposits of the West Pacific continental margins intraplate basaltic fields. Ore Geology Reviews, 34 (1) 200-215 doi:10.1016/j.oregeorev.2008.04.006 | Journal (article/letter/editorial) | | 2001). A rare corundum-sapphirine bearing garnet granulite xenolith was described from a basanite dyke intersecting...blue sapphires from non-basaltic ļ¬elds (Ilakaka, Madagascar; Ratnapura, Sri Lanka; Mogok, Myanmar) to those...crustal component, such as a lower crustal Al-rich granulite having a Ī“ 18O range of + 5 to 14ā° (Hoefs, 1997;...component would match an Alrich lower crustal granulite with Ī“ 18O in the range of +5 to 14ā° (Hoefs, 1997)...isotope systematics of gem corundum deposits in Madagascar: relevance for their geological origin. Mineralium |  | | Journal (issue) | | and Hope Diamonds . . . Opals from Ethiopiaāand Madagascar Composite Turquoise . . . Microtomography of...114 New Occurrence of Fire Opal from Bemia, Madagascar Martina Simoni, Franca Caucia, Ilaria Adamo,...the proximity to San Diegoās historic pegmatite district, we will offer field trips to working gem mines...This pattern has been observed previously in type II diamonds, and studies suggest that the cell walls...in cathodoluminescence spectra and images of type II high-pressure synthetic diamond produced with high |  | | Journal (issue) | | had to go on. GEMS & GEMOLOGY WINTER 2019 Madagascar are from metamorphic deposits, but the deposits...basaltsātwo very different deposits, yet both from Madagascar. As stated earlier, when geographic origin determination...ring, courtesy of Ronald Ringsrud; a 7.04 ct Madagascar sapphire, courtesy of Mayer & Watt; and an exceptional...such as in Sri Lanka (Ratnapura, Elahera) and Madagascar (Ilakaka), produce the highest-quality sapphires...(Type I) and (2) tectonic-metamorphic-related (Type II). Several subtypes are defined and especially Type |  | | Book | | (Itabira), Colombia (Coscuez), Ethiopia (Shakisso), Madagascar (Mananjary), Russia (Ural mountains), Zambia...I: muscovite, tourmaline, albite, and quartz; Zone II: K-feldspar (microcline), quartz, and albite; Zone...medium-grained albite and quartz (Figure 3aāc); Zone II hosting homogeneous medium-grained K-feldspar (microcline)...between Zones II and III (Figure 3e,f), and spodumene and/or cassiterite in Zones I and II are common ([6]...microcline and quartz crystals collected from Zone II. Muscovite grains gathered from Zone I were suitable |  | | Journal (article/letter/editorial) | | between 40 and 90%, It is generally be found in granulite facies terrains and formed under high P and T...perhaps in the presence of a water-rich phase. Granulite is a ļ¬ne to medium-grained metamorphic rocks composed...Gabbro Gneiss Granite Granodiorite Granophyre Granulite Greywacke Greenschist Gypcrete Harzburgite Hornblendite...sediments but rarely in volcanic rocks e.g., Cobalt district of Ontario, Canada, Wittichen, Richelsdorf, Bieber...Jachymov, Czech Republic, Black Hawk District, USA, Batopilas District, Mexico (Fig. 04.01). These vein-type | | | Journal (article/letter/editorial) | | between 40 and 90%, It is generally be found in granulite facies terrains and formed under high P and T...perhaps in the presence of a water-rich phase. Granulite is a ļ¬ne to medium-grained metamorphic rocks composed...Gabbro Gneiss Granite Granodiorite Granophyre Granulite Greywacke Greenschist Gypcrete Harzburgite Hornblendite...sediments but rarely in volcanic rocks e.g., Cobalt district of Ontario, Canada, Wittichen, Richelsdorf, Bieber...Jachymov, Czech Republic, Black Hawk District, USA, Batopilas District, Mexico (Fig. 04.01). These vein-type |
|
