 | 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) | | 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...rubies from the recently discovered Didy mine in Madagascar also command high prices [19]. A set of eight...Ambohimandrosoa, Antsirabe area, cm2.1 × 1.3 andcm 1.7×cm 1 cm × 11.7cm) Antsirabe area, Madagascar. Collection: |  | | 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...of formation: (Type I) magmatic-related and (Type II) metamorphic-related. Type I is characterized by |  | 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...environments [50]. An Eocene (~52–53 Ma) high-pressure eclogite- to blueschist-facies metamorphism was followed...diaspore; 420 to 500 ◦ C (appearance of biotite) for zone II; 500 ◦ C to 540–580 ◦ C (disappearance of chloritoid)...metamorphism; (ii) syn-metamorphism depletion in O related to hydration subduction and metamorphism; (ii) syn-metamorphism |  | | Journal (issue) | | and Hope Diamonds . . . Opals from Ethiopia—and Madagascar Composite Turquoise . . . Microtomography of...114 New Occurrence of Fire Opal from Bemia, Madagascar Martina Simoni, Franca Caucia, Ilaria Adamo,...the proximity to San Diego’s 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...basalts—two 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 3a–c); 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) | | Dacite Diabase Diorite Dolcrete Dolerite Dunite Eclogite Enderbite Essexite Evaporite Ferricrete Foskorite...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...gemological products (Fig. 04.10). In the Marlborough district of Queensland, Australia, it occurs within the...Complexes, USA, and the Russian NoriĺskTalnakh District (Cabri and Traill, 1966). 4a A: As an example | | | Journal (article/letter/editorial) | | Dacite Diabase Diorite Dolcrete Dolerite Dunite Eclogite Enderbite Essexite Evaporite Ferricrete Foskorite...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...gemological products (Fig. 04.10). In the Marlborough district of Queensland, Australia, it occurs within the...Complexes, USA, and the Russian NoriĺskTalnakh District (Cabri and Traill, 1966). 4a A: As an example |
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