| Adamo, Ilaria, Gatta, G. Diego, Rotiroti, Nicola, Diella, Valeria, Pavese, Alessandro (2011) Green andradite stones: gemmological and mineralogical characterisation. European Journal of Mineralogy, 23 (1) 91-100 doi:10.1127/0935-1221/2011/0023-2079 | Journal (article/letter/editorial) | 91–100 Published online December 2010 Green andradite stones: gemmological and mineralogical characterisation...multi-methodological investigation of natural gem-quality andradite crystals occurring in serpentinites (Val Malenco...and Kaghan, Pakistan), or in skarn rocks (Erongo, Namibia, and Antetezambato, Madagascar) has been performed...show that these green garnets are almost pure andradite [Adr (Ca3Fe2Si3O12).96.1 mol%]. The Cr-content...substitution [i.e., (SiO4)4 $ (O4H4)4]. Key-words: andradite, gem, EMPA-WDS, UV-Vis-NIR spectroscopy, MID-IR | | | Journal (article/letter/editorial) | ELEMENTS, INCLUDING THE REE, IN GEM-QUALITY GREEN ANDRADITE FROM CLASSIC LOCALITIES Rosangela BOCCHIO§ Dipartimento...Milan, Italy Abstract Crystals of gem-quality andradite (variety “demantoid”) from Val Malenco, Italy...deposits of the world (Russia, Iran, Pakistan, Namibia, Madagascar). They are all of gem quality and vary...pure andradite (Adr ≥ 98 mol.%) to members of andradite–uvarovite (Adr81–96Uv3–18) or andradite–grossular...exception of the sample from Namibia, showing a composition varying from pure andradite to almost pure grossular | | | Journal (article/letter/editorial) | heterogeneity in garnet from Kakanui (New Zealand) and Erongo (Namibia) MAJA UROSEVIC1,*, OLIVER NEBEL2, JOSÉ ALBERTO...garnets (skarn) from two different localities in Erongo, Namibia. The in situ analyses are complemented by bulk...(d18OVSMOW = 5.67 ± 0.02‰). Magmatic garnet from Erongo, Namibia, is rich in Mn and Fe2þ and very poor in Ca...garnet from Namibia is rich in Ca and Fe3þ and shows strong zonation along the andradite–grossular join...separates are heterogeneous in both crustal garnet from Erongo with a large spread ranging from 0.15 to þ0.30‰ | | | Thesis/Dissertation | the end-members pyrope, almandine, spessartine, andradite, grossular, and uvarovite. The large variation...species: ugrandite (uvarovite, grossular and andradite) and pyralspite (pyrope, spessartine and almandine)...unusual compositions were reported such as pyrope-andradite, spessartine-grossular, and almandine-grossular.................................... 19 2.5.3. Andradite ..................................................................... 22 2.5.3.1.2.4. Erongo Province, Namibia ..................................... | | | Report (issue) | the series. This 3.3 cm tall andradite on hematite is from the Wessels Mine near Hotazel in northern Cape...Cover: Grossular on diopside; 7.1 cm tall Jeffrey Mine, Asbestos, Richmond County, Quebec, Canada Paul...the color of some 50 percent of the green gem andradite (variety "demantoid") originating in Russia is...Inclusions BY MICKEY E. GUNTER 34 Classic Garnets: Andradite BY JOACHIM ZANG 38 Above: Childeric 's bees...members). Of these fifteen species, six almandine, andradite, grossular, pyrope, spessartine, and uvarovite-are | | | Journal (issue) | by von Knorring and Sahama from northwest ern Namibia, namibite has been identified from a number of...Elias mine, Czech Republic Mrazek et al. (1994) report an occurrence of namibite from the Elias mine, Jachymov...5’6Evans-Lou pegmatite, Quebec CZECH REPUBLIC 7Elias mine, Jachymov ENGLAND 8Buckbarrow Beck, Cumbria GERMANY...Hechtsberg quarry, Hausach NAMIBIA 10Khorixas UNITED STATES 3Stewart mine, Pala district, California...pucherite, U-minerals Hydrothermal quartz vein Lodi #4 mine, near Chilcoot, California Bismite, bismutite, | | | Book (edition) | Linopolis, Brazil, H Page 13: Gold, 35 mm.Eagle's est Mine, California, G Publi!>hed by Grdllit.u.o. Stefanikova43...abbreviated, e.g. canton (Switzerland), vilayet (Turkey), region (Chile), kray and oblast (Russia). The country...by Mobutu, and is now the Katanga administrative region again. The former Kivu province is now divided...United States or of the Upper Silesian historical region in Poland, where the importance of ore-bearing...Rice, Dolores co., both Colorado, at the Questa mine, Taos co., New 1994. Abernathyite K2[(UOJ 2l(AsO_J2]•6HzO | | | Book | Tsumcb, Namibia and Chessy. France. Crystals up to 140mm (5'A in) long occurred in the Ray mine and in...100 mm (4 in) long, come also from the San Gcnaro Mine in Huancavclica and Uchucchaqua, Peru. New finds...many localities in California, USA (Colorado Quartz mine. Nigger Hill and others). Fine leaf gold comes from...110 mm (47.6 in) long were very rare in Ground Hog mine, Gilman, Colorado, USA. The largest known sheets...of crystallized gold occurred in the Jamestow n mine. California, USA, where a cavity, which yielded | | | Book | Tsumeb, Namibia and Chessy, France. Crystals up to 140mm (5½ in) long occurred in the Ray mine and in...100 mm (4 in) long, come also from the San Genaro Mine in Huancavelica and Uchucchaqua, Peru. New finds...Dorado, California, US.A. Gold, 68 mm, Eagle's Nest Mine, California, US.A. Gold gold on it. Typical aggregates...many localities in California, USA (Colorado Quartz mine, Nigger Hill and others). Fine leaf gold comes from...mm (4 5/i6 in) long were very rare in Ground Hog mine, Gilman, Colorado, USA. The largest known sheets | | | Journal (issue) | looking squarely into the top of a stone at the culet region; doubling is only seen when focusing deeper at...gemstone material in facets, but not in the culet region (here somewhat out of focus) because the view is...2300°C; • growing crystal 100°C cooler than the feed region; • seed crystal orientation slightly off axis and...relative transparency in the near-ultraviolet, a region where near-colourless diamond is transparent and...diamondiferous gneiss and marble from the Lake KumdyKol region of the Kokchetav Massif, N Kazakhstan. The examination |
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Namgar Mine, Usakos, Karibib Constituency, Erongo Region, Namibia